Can GPS be *too* accurate? Do I need some XTE??

[Icebound]

In the "good old" VOR days, it must have been pretty difficult to fly down
the centerline of an airway (or of any direct track).

So an eastbound VFR/IFR aircraft descending from 7500/7000 to his
destination, was more than likely to avoid traffic... on the reciprocal
track passing him by at 6500 or 6000... by some significant horizontal
error-distance, even if they didn't see each other (big sky theory :-) ).

GPS horizontal accuracy with WAAS is already in the order of magnitude of a
Cessna's wingspan, and some are talking about getting it down to mere
inches.

So the question is: If my Westbound Cessna at 6000 feet (with the autopilot
keeping it happily on the GPS-track centerline) meets the descending Bonanza
on the reciprocal track between the same two airports (using a similar
GPS/a-p combo), there is a distinct possibility that the horizontal
clearance may be zero...

....so is there anything in the current crop of GPS and/or Autopilot systems
that allow me to maintain a small cross-track error of my choosing, without
actually entering off-navaid-off-airport waypoints? ...or do we care; am I
overly concerned???

[Peter Duniho]

"Icebound" > wrote in message
...
> [...]
> ...so is there anything in the current crop of GPS and/or Autopilot
> systems that allow me to maintain a small cross-track error of my
> choosing, without actually entering off-navaid-off-airport waypoints?
> ...or do we care; am I overly concerned?

You are not overly concerned, it does present a greater chance of a
collision.

I haven't heard of a GPS unit that allows the user to set some sort of
"offset" from a course to follow, but it wouldn't surprise if such a feature
did exist somewhere.

Beyond that, the "big sky theory" still works reasonably well. Two
airplanes in level flight on opposite headings on the same airway stand a
decently improved chance of running into each other if they are using GPS.
But when at least one is climbing, they share their altitude for such a
short period of time, I would think that the *actual* risk is relatively
low, even if the GPS does significantly increase the risk when compared to a
VOR receiver.

In any case, even before GPS it was still reasonably important to be alert
for other traffic while traveling on airways (even beyond the general
importance of doing so at all times). GPS increases the risk, but the risk
was always there and I've certainly had my share of close encounters (under
1 mile) flying on airways with a VOR receiver.

Pete

[Roy Smith]

"Peter Duniho" > wrote:
> I haven't heard of a GPS unit that allows the user to set some sort of
> "offset" from a course to follow, but it wouldn't surprise if such a feature
> did exist somewhere.

The CNX-80 / GNS-480 has it. It's called "Parallel Track". You tell it
if you want to fly left or right of course and by how much (in 1/10's of
a mile IIRC), and it invents a new course line for you to follow.

I believe the Apollo GX-60 had it too. The story I heard was the CAP
wanted to buy a bunch of GX-60's, but insisted Apollo add the Parallel
Track feature to facilitate flying grid search patterns.

[John R. Copeland]

"Icebound" > wrote in message =
...
>=20
> So the question is: If my Westbound Cessna at 6000 feet (with the =
autopilot=20
> keeping it happily on the GPS-track centerline) meets the descending =
Bonanza=20
> on the reciprocal track between the same two airports (using a similar =

> GPS/a-p combo), there is a distinct possibility that the horizontal=20
> clearance may be zero...
>

The July 2004 issue of "International Procedures News" from
Flight Safety Inc., carried an item exactly about that,
in regard to the North Atlantic routes.
Here is one paragraph, which I quote from that article:

"Following a successful trial in the West Atlantic Route System (WATRS),
it has been determined that by allowing aircraft conducting oceanic =
flights
to fly lateral offsets not exceeding two NM right of centerline,
an additional safety margin will be provided and will mitigate the risk
of collision when non-normal events such as operational altitude =
deviation errors
and turbulence induced altitude deviations occur."

The remainder of the article describes the 1-nm or 2-nm offsets allowed,
and only to the right of centerline, with effective date of June 10, =
2004.

The name of this concept is "Strategic Lateral Offset Procedure",
so everyone can understand they've now added SLOP to the route system!
As Dave Barry might say, I am not making this up.
---JRC---

[Blueskies]

"Icebound" > wrote in message ...
> In the "good old" VOR days, it must have been pretty difficult to fly down the centerline of an airway (or of any
> direct track).
>
> So an eastbound VFR/IFR aircraft descending from 7500/7000 to his destination, was more than likely to avoid
> traffic... on the reciprocal track passing him by at 6500 or 6000... by some significant horizontal error-distance,
> even if they didn't see each other (big sky theory :-) ).
>
> GPS horizontal accuracy with WAAS is already in the order of magnitude of a Cessna's wingspan, and some are talking
> about getting it down to mere inches.
>
> So the question is: If my Westbound Cessna at 6000 feet (with the autopilot keeping it happily on the GPS-track
> centerline) meets the descending Bonanza on the reciprocal track between the same two airports (using a similar
> GPS/a-p combo), there is a distinct possibility that the horizontal clearance may be zero...
>
> ...so is there anything in the current crop of GPS and/or Autopilot systems that allow me to maintain a small
> cross-track error of my choosing, without actually entering off-navaid-off-airport waypoints? ...or do we care; am I
> overly concerned???
>
>

At midcourse, add a waypoint offset to one side or the other by a couple of miles. The enroute time would be changed
minimally...

[Stan Prevost]

"Peter Duniho" > wrote in message
...
> I haven't heard of a GPS unit that allows the user to set some sort of
> "offset" from a course to follow, but it wouldn't surprise if such a
> feature did exist somewhere.
>

My Northstar M3 has parallel track offset, as does the GX-60

[Fox Hound]

> "Peter Duniho" > wrote:
> > I haven't heard of a GPS unit that allows the user to set some sort of
> > "offset" from a course to follow, but it wouldn't surprise if such a
feature
> > did exist somewhere.
>
> The CNX-80 / GNS-480 has it. It's called "Parallel Track". You tell it
> if you want to fly left or right of course and by how much (in 1/10's of
> a mile IIRC), and it invents a new course line for you to follow.
>
> I believe the Apollo GX-60 had it too. The story I heard was the CAP
> wanted to buy a bunch of GX-60's, but insisted Apollo add the Parallel
> Track feature to facilitate flying grid search patterns.

Parallel track and the grid search feature are not related to each other.
The GX series has the search grid lines on its display so CAP pilots can
stay oriented in their search grid. But even that wasn't as useful because
the grid lines they did show were not at the correct level. IIRC, you want
7.5 minute grid lines and the GX only showed down to 15 minute grid lines.

[Stan Gosnell]

Roy Smith > wrote in
:

> "Peter Duniho" > wrote:
>> I haven't heard of a GPS unit that allows the user to set some sort
>> of "offset" from a course to follow, but it wouldn't surprise if such
>> a feature did exist somewhere.
>
> The CNX-80 / GNS-480 has it. It's called "Parallel Track". You tell
> it if you want to fly left or right of course and by how much (in
> 1/10's of a mile IIRC), and it invents a new course line for you to
> follow.

The Trimble 2102 has it, and so do most other units.

--
Regards,

Stan

[Julian Scarfe]

"Icebound" > wrote in message
...

> ...so is there anything in the current crop of GPS and/or Autopilot
systems
> that allow me to maintain a small cross-track error of my choosing,
without
> actually entering off-navaid-off-airport waypoints? ...or do we care; am I
> overly concerned???

You're certainly not alone in being concerned.

http://www.pprune.org/go.php?go=/pub/tech/MidAir.html
http://tsb.gc.ca/en/reports/air/1995/a95h0008/a95h0008.asp

Julian Scarfe

[[email protected]]

Blueskies wrote:

>
>
> At midcourse, add a waypoint offset to one side or the other by a couple of miles. The enroute time would be changed
> minimally...

But, that wouldn't be a parallel offset and would result in crossing the two end points precisely on course.

Also, the offset should be much smaller than 2 miles for domestic airspace operations.

[[email protected]]

"John R. Copeland" wrote:

> "Icebound" > wrote in message ...
>
>
> The remainder of the article describes the 1-nm or 2-nm offsets allowed,
> and only to the right of centerline, with effective date of June 10, 2004.
>
> The name of this concept is "Strategic Lateral Offset Procedure",
> so everyone can understand they've now added SLOP to the route system!
> As Dave Barry might say, I am not making this up.
> ---JRC---

Keep in mind those offsets are in oceanic airspace where the route width is 25 or 30 miles, centerline to
edge. Along a domestic airway, offsets of those magnitude would be far too large. An offset of 1/10 of a
mile would probably be effective without creating an issue with compliance with FAR 91.189. (although the feds
might not buy that rationale ;-)

[[email protected]]

If the weather is IMC you are well advised to remain on centerline. If it is
VMC, and your equipment will support parallel track offset, then 1/10 of a mile
is probably going to mitigate your concerns. But, if operating IFR it is
essential to terminate offset operations before beginning an instrument approach
procedure.

If your equipment won't support parallel offset, then your only remaining option
is to fly the autopilot in heading mode and try to keep the XTRK error at some
value approximating 1/10 of a n.m.

Icebound wrote:

> In the "good old" VOR days, it must have been pretty difficult to fly down
> the centerline of an airway (or of any direct track).
>
> So an eastbound VFR/IFR aircraft descending from 7500/7000 to his
> destination, was more than likely to avoid traffic... on the reciprocal
> track passing him by at 6500 or 6000... by some significant horizontal
> error-distance, even if they didn't see each other (big sky theory :-) ).
>
> GPS horizontal accuracy with WAAS is already in the order of magnitude of a
> Cessna's wingspan, and some are talking about getting it down to mere
> inches.
>
> So the question is: If my Westbound Cessna at 6000 feet (with the autopilot
> keeping it happily on the GPS-track centerline) meets the descending Bonanza
> on the reciprocal track between the same two airports (using a similar
> GPS/a-p combo), there is a distinct possibility that the horizontal
> clearance may be zero...
>
> ...so is there anything in the current crop of GPS and/or Autopilot systems
> that allow me to maintain a small cross-track error of my choosing, without
> actually entering off-navaid-off-airport waypoints? ...or do we care; am I
> overly concerned???

[[email protected]]

Stan Gosnell wrote:

> The Trimble 2102 has it, and so do most other units.
>

Do you know whether the Garmin 400/500 series (other than the 480) have it?

[Jim Harper]

"Icebound" > wrote in message >...
> So the question is: If my Westbound Cessna at 6000 feet (with the autopilot
> keeping it happily on the GPS-track centerline) meets the descending Bonanza
> on the reciprocal track between the same two airports (using a similar
> GPS/a-p combo), there is a distinct possibility that the horizontal
> clearance may be zero...
>
> ...so is there anything in the current crop of GPS and/or Autopilot systems
> that allow me to maintain a small cross-track error of my choosing, without
> actually entering off-navaid-off-airport waypoints? ...or do we care; am I
> overly concerned???

As others have pointed out, the GNS 480/CNX 80 does allow a
cross-track error. I did want to make one small philosophical
point...here in the deep south, we generally get direct routing. If
you have the capability, and you ask for the direct routing, you
generally are increasing your safety (by an admittedly tiny amount).
Further, anyone who is flying VFR and uses the airways is also
increasing his/her risk by that same small amount.

I do doubt that ATC will descend you through another aircraft on the
same airway, so the chances of meeting an IFR aircraft is
diminishingly small, but your concern is most likely regarding the VFR
aircraft sharing the airway.

Hence this discussion is of the "how many angels can dance on the head
of a pin" sort...making it perfect for USENET. And the take-home
points are(IMO) fly direct whenever allowed. Generate your courseline
from some NON-standard point. That is, don't go direct from some
intersection or from the runway...go from some offset point...avoiding
the other guy (most likely VFR) doing the same thing from your
destination. Don't use airways unless you must. And when you fly the
Atlantic (in a non-radar environment)...or the non-radar environments
of the USA...use SLOP!

Jim

[[email protected]]

Jim Harper wrote:

> . And when you fly the
> Atlantic (in a non-radar environment)...or the non-radar environments
> of the USA...use SLOP!
>

SLOP is approved for oceanic. Do you know if it is approved for non-radar environments of the USA? If so, what
are the numbers to use? How do I determine when I am in a non-radar environment in the USA?

[Dave Butler]

wrote:

> How do I determine when I am in a non-radar environment in the USA?

When you hear "radar contact lost" or when you don't hear "radar contact".

[Jose]

> [how and whether to fly an offset on a GPS track]

Just hand fly. You can hand fly any offset you like.

Jose
--
Freedom. It seemed like a good idea at the time.
for Email, make the obvious change in the address.

[Bill Denton]

I noticed the later posts referenced a set of "rules" for setting up the
"error", but absent those, you are back to the same old game of chance.
What's to prevent another pilot from picking a corresponding "error" that
would still maintain the head-on courses?

And I don't know if this is a trick question, but if you are at 6000 (no
+500) wouldn't you be on an IFR flight plan, talking to ATC, and receiving
traffic advisories?





"Icebound" > wrote in message
...
> In the "good old" VOR days, it must have been pretty difficult to fly down
> the centerline of an airway (or of any direct track).
>
> So an eastbound VFR/IFR aircraft descending from 7500/7000 to his
> destination, was more than likely to avoid traffic... on the reciprocal
> track passing him by at 6500 or 6000... by some significant horizontal
> error-distance, even if they didn't see each other (big sky theory :-) ).
>
> GPS horizontal accuracy with WAAS is already in the order of magnitude of
a
> Cessna's wingspan, and some are talking about getting it down to mere
> inches.
>
> So the question is: If my Westbound Cessna at 6000 feet (with the
autopilot
> keeping it happily on the GPS-track centerline) meets the descending
Bonanza
> on the reciprocal track between the same two airports (using a similar
> GPS/a-p combo), there is a distinct possibility that the horizontal
> clearance may be zero...
>
> ...so is there anything in the current crop of GPS and/or Autopilot
systems
> that allow me to maintain a small cross-track error of my choosing,
without
> actually entering off-navaid-off-airport waypoints? ...or do we care; am I
> overly concerned???
>
>
>
>
>
>
>
>

[Peter R.]

Bill Denton ) wrote:

> And I don't know if this is a trick question, but if you are at 6000 (no
> +500) wouldn't you be on an IFR flight plan, talking to ATC, and receiving
> traffic advisories?

In the US and outside of class B airspace, it is the pilot, not ATC, who
is ultimately responsible for IFR/VFR traffic separation. A VFR traffic
advisory to an IFR aircraft is a courtesy offered by ATC; it is not a
guarantee.

--
Peter

[Bill Denton]

"Peter R." > wrote in message
...
> Bill Denton ) wrote:
>
> > And I don't know if this is a trick question, but if you are at 6000 (no
> > +500) wouldn't you be on an IFR flight plan, talking to ATC, and
receiving
> > traffic advisories?
>
> In the US and outside of class B airspace, it is the pilot, not ATC, who
> is ultimately responsible for IFR/VFR traffic separation. A VFR traffic
> advisory to an IFR aircraft is a courtesy offered by ATC; it is not a
> guarantee.
>
> --
> Peter
>
You might want to rethink your reply.

A pilot in clouds or other IMC cannot provide separation to any traffic he
cannot see.

[Peter R.]

Bill Denton ) wrote:

> You might want to rethink your reply

Easy there, Bill. There is no need for that.

> A pilot in clouds or other IMC cannot provide separation to any traffic he
> cannot see.

I am discussing IFR/VFR separation, not IFR/IFR separation. Hopefully,
no VFR aircraft will be in IMC, but that point is irrelevant since most
times ATC does not know if it is IMC or VMC; they only have blips on
their screen.

Consider this: It is quite possible that a) a VFR aircraft is climbing
or descending through an IFR aircraft's cruise altitude, or b) an IFR
cruise altitude is below 3,000 AGL, which means that a VFR aircraft
could be at any altitude 3,000 feet AGL or below s/he desires, including
that IFR aircraft's altitude.

Will ATC provide traffic callouts and or vectors around VFR traffic in
either scenario above? Most likely. Are US controllers required to?
Outside of class B airspace, the answer is no.

--
Peter

[Bill Denton]

I had a minute so I looked this up; you misread the AIM.

4-4-10. IFR SEPARATION STANDARDS

b. Separation will be provided (by ATC - my note) between all aircraft
operating on IFR flight plans except during that part of the flight (outside
of Class B airspace or a TRSA) being conducted on a VFR-on-top/VFR
conditions clearance. Under these conditions, ATC may issue traffic
advisories, but it is the sole responsibility of the pilot to be vigilant so
as to see and avoid other aircraft.

To paraphrase and clarify: If you are "outside of Class B airspace or a
TRSA" and flying on a "VFR-on-top/VFR conditions clearance", "ATC may issue
traffic advisories, but it is the sole responsibility of the pilot to be
vigilant so as to see and avoid other aircraft". Otherwise, "Separation will
be provided (by ATC - my note) between all aircraft operating on IFR flight
plans".




"Peter R." > wrote in message
...
> Bill Denton ) wrote:
>
> > And I don't know if this is a trick question, but if you are at 6000 (no
> > +500) wouldn't you be on an IFR flight plan, talking to ATC, and
receiving
> > traffic advisories?
>
> In the US and outside of class B airspace, it is the pilot, not ATC, who
> is ultimately responsible for IFR/VFR traffic separation. A VFR traffic
> advisory to an IFR aircraft is a courtesy offered by ATC; it is not a
> guarantee.
>
> --
> Peter
>
>
>
>
>

[SelwayKid]

"Icebound" > wrote in message >...
> In the "good old" VOR days, it must have been pretty difficult to fly down
> the centerline of an airway (or of any direct track).
>
> So an eastbound VFR/IFR aircraft descending from 7500/7000 to his
> destination, was more than likely to avoid traffic... on the reciprocal
> track passing him by at 6500 or 6000... by some significant horizontal
> error-distance, even if they didn't see each other (big sky theory :-) ).
>
> GPS horizontal accuracy with WAAS is already in the order of magnitude of a
> Cessna's wingspan, and some are talking about getting it down to mere
> inches.
>
> So the question is: If my Westbound Cessna at 6000 feet (with the autopilot
> keeping it happily on the GPS-track centerline) meets the descending Bonanza
> on the reciprocal track between the same two airports (using a similar
> GPS/a-p combo), there is a distinct possibility that the horizontal
> clearance may be zero...
>
> ...so is there anything in the current crop of GPS and/or Autopilot systems
> that allow me to maintain a small cross-track error of my choosing, without
> actually entering off-navaid-off-airport waypoints? ...or do we care; am I
> overly concerned???

********************************************
Way overly concerned. I've been flying nearly 50 years, logged over
21,700 hours in general aviation, done a lot of IFR, without a lot of
GPS. I've not had any problems. As for the offset idea, what is to
prevent the other pilot from doing an offset that puts them directly
in your path? Whatever happened to eyeballs and watching out for
traffic?
As for being difficult to fly the VOR, it was/is no more difficult
than flying a compass heading and holding it.....which many pilots
seem unable to do anymore. They would prefer that electronic gadgets
do their flying for them and no thoughts as to what happens when the
electrodes take a vacation.
Ol Shy & Bashful - and unrepentant demanding grumpy old CFII

[Peter R.]

Bill Denton ) wrote:

> I had a minute so I looked this up; you misread the AIM.

You and I have been through this before. The AIM is not regulatory and
perhaps you might want to re-read that passage. It appears to me that
you have misinterpreted it.

Let's break this down:

> b. Separation will be provided (by ATC - my note) between all aircraft
> operating on IFR flight plans except during that part of the flight (outside
> of Class B airspace or a TRSA) being conducted on a VFR-on-top/VFR
> conditions clearance.

Please show me where in that passage above does it say anything about
IFR aircraft being separated from VFR aircraft. Note the operative
word "between" being used there. I interpret the passage to be
discussing IFR aircraft being separated from IFR aircraft.

> To paraphrase and clarify: If you are "outside of Class B airspace or a
> TRSA" and flying on a "VFR-on-top/VFR conditions clearance", "ATC may issue
> traffic advisories, but it is the sole responsibility of the pilot to be
> vigilant so as to see and avoid other aircraft". Otherwise, "Separation will
> be provided (by ATC - my note) between all aircraft operating on IFR flight
> plans".

There, you stated it, too. "BETWEEN all aircraft operating on IFR
flight plans." Where does it say anything about ATC's responsibility
about separation between those aircraft on IFR flight plans and those on
VFR flight plans? Not in that passage it doesn't.



--
Peter

[Bill Denton]

My comments in text:



"Peter R." > wrote in message
...
> Bill Denton ) wrote:
>
> > I had a minute so I looked this up; you misread the AIM.
>
> You and I have been through this before. The AIM is not regulatory and
> perhaps you might want to re-read that passage. It appears to me that
> you have misinterpreted it.

Regulatory/no-regulatory is immaterial. This portion of the AIM simply
states what services will be offered to pilots by ATC.



>
> Let's break this down:
>
> > b. Separation will be provided (by ATC - my note) between all aircraft
> > operating on IFR flight plans except during that part of the flight
(outside
> > of Class B airspace or a TRSA) being conducted on a VFR-on-top/VFR
> > conditions clearance.
>
> Please show me where in that passage above does it say anything about
> IFR aircraft being separated from VFR aircraft. Note the operative
> word "between" being used there. I interpret the passage to be
> discussing IFR aircraft being separated from IFR aircraft.

The separation of VFR/IFR aircraft is not covered in this section; the
separation of ALL aircraft is discussed in the previous section.

The purpose of this section is to remind VFR-on-top-pilots that while they
are on an IFR flight plan, ATC has allowed them to deviate and fly under VFR
rules (including see and avoid) and that ATC is not obligated to provide
traffic guidance.


>
> > To paraphrase and clarify: If you are "outside of Class B airspace or a
> > TRSA" and flying on a "VFR-on-top/VFR conditions clearance", "ATC may
issue
> > traffic advisories, but it is the sole responsibility of the pilot to be
> > vigilant so as to see and avoid other aircraft". Otherwise, "Separation
will
> > be provided (by ATC - my note) between all aircraft operating on IFR
flight
> > plans".
>
> There, you stated it, too. "BETWEEN all aircraft operating on IFR
> flight plans." Where does it say anything about ATC's responsibility
> about separation between those aircraft on IFR flight plans and those on
> VFR flight plans? Not in that passage it doesn't.

As I stated above, VFR-on-top operations are conducted on IFR flight plans
and the purpose of this section is to explain the services to be provided or
not provided by ATC to VFR-on-top pilots.



>
>
>
> --
> Peter
>
>
>
>
>

[Peter R.]

Bill Denton ) wrote:

> The separation of VFR/IFR aircraft is not covered in this section; the
> separation of ALL aircraft is discussed in the previous section.

Then why are you and I having this disagreement?

You asked about separation of an aircraft flying at 6,000 feet,
presumably on an IFR flight plan, I maintained all along about the fact
that IFR flights are not separated from VFR flights and presented two
scenarios where an IFR aircraft at 6,000 feet might encounter a VFR
aircraft, yet you quote a passage that admittedly has nothing to do with
my posts.


> The purpose of this section is to remind VFR-on-top-pilots that while they
> are on an IFR flight plan, ATC has allowed them to deviate and fly under VFR
> rules (including see and avoid) and that ATC is not obligated to provide
> traffic guidance.

I am not sure what your point about VFR-on-top is, but as a reminder to
you, in the US VFR-on-TOP is a specific IFR clearance that must be
requested.

Simply being on an IFR flight plan in visual conditions is not the same
as VFR-on-top. In the case of the IFR flight in VMC, the pilot is still
guaranteed ATC separation between other IFR aircraft, but not VFR
aircraft (excluding class B).

Thus, to your question in your first post, an IFR aircraft at 6,000 feet
is still at risk of a mid-air collision.

--
Peter

[Peter Duniho]

"Bill Denton" > wrote in message
...
> [...]
> As I stated above, VFR-on-top operations are conducted on IFR flight plans
> and the purpose of this section is to explain the services to be provided
> or
> not provided by ATC to VFR-on-top pilots.

"VFR-on-top" is still an IFR operation. That's not what Peter is talking
about.

Basically, your belief that a pilot flying on an instrument flight plan is
immune from the scenario posted in the original message is simply wrong.
All it takes is a pilot on an instrument flight plan (satisfying the 6000'
cruise altitude), and another pilot flying VFR (not "VFR-on-top"...just
plain old VFR) climbing on the airway as described by the original poster.

Pete

[Bill Denton]

VFR-on-top:

1. Is requested by pilot flying on an IFR flight plan.

2. Is flown under Visual Flight Rules.

3. May or may not be flown following the IFR flightplan's route.

4. Ends when the pilot cancels IFR or returns to the original flight plan at
a waypoint on that plan.

Very simple; it's in the book.

-----------------------------------------------------

A pilot flying VFR is required to observe "see and avoid". One pilot
observing "see and avoid" and taking appropriate evasive action can avoid a
collision.

If a VFR pilot is climbing/descending, it is his responsibility to avoid
pilots above him or below him.

A pilot flying IFR under VMC who is not observing "see and avoid" is not a
very smart pilot.


"Peter Duniho" > wrote in message
...
> "Bill Denton" > wrote in message
> ...
> > [...]
> > As I stated above, VFR-on-top operations are conducted on IFR flight
plans
> > and the purpose of this section is to explain the services to be
provided
> > or
> > not provided by ATC to VFR-on-top pilots.
>
> "VFR-on-top" is still an IFR operation. That's not what Peter is talking
> about.
>
> Basically, your belief that a pilot flying on an instrument flight plan is
> immune from the scenario posted in the original message is simply wrong.
> All it takes is a pilot on an instrument flight plan (satisfying the 6000'
> cruise altitude), and another pilot flying VFR (not "VFR-on-top"...just
> plain old VFR) climbing on the airway as described by the original poster.
>
> Pete
>
>

[Bill Denton]

"Peter R." > wrote in message
...
> Bill Denton ) wrote:
>
> > The separation of VFR/IFR aircraft is not covered in this section; the
> > separation of ALL aircraft is discussed in the previous section.
>
> Then why are you and I having this disagreement?
>
> You asked about separation of an aircraft flying at 6,000 feet,
> presumably on an IFR flight plan, I maintained all along about the fact
> that IFR flights are not separated from VFR flights and presented two
> scenarios where an IFR aircraft at 6,000 feet might encounter a VFR
> aircraft, yet you quote a passage that admittedly has nothing to do with
> my posts.

No, the orignal poster presented the scenario. I simply pointed out that a
6000 feet he would be on an IFR flight plan, talking to ATC, and receiving
traffic from ATC.

You introduced the passage and misinterpreted it. I provided a correct
interpretation.
>
>
> > The purpose of this section is to remind VFR-on-top-pilots that while
they
> > are on an IFR flight plan, ATC has allowed them to deviate and fly under
VFR
> > rules (including see and avoid) and that ATC is not obligated to provide
> > traffic guidance.
>
> I am not sure what your point about VFR-on-top is, but as a reminder to
> you, in the US VFR-on-TOP is a specific IFR clearance that must be
> requested.

And if you are granted that clearance, you will be flying under what are
essentially Visual Flight Rules, you will be allowed to deviate from your
as-filed flight plan, and ATC is not obligated to provide traffic guidance
outside of Class B's and TRSA's.They still have an open IFR flight plan;
they must either cancel IFR, or they must rejoin that flight plan at a
waypoint on the plan and continue fllying that flight plan.


>
> Simply being on an IFR flight plan in visual conditions is not the same
> as VFR-on-top. In the case of the IFR flight in VMC, the pilot is still
> guaranteed ATC separation between other IFR aircraft, but not VFR
> aircraft (excluding class B).
>
> Thus, to your question in your first post, an IFR aircraft at 6,000 feet
> is still at risk of a mid-air collision.

But a pilot flying on a VFR flight plan is required to observe "see and
avoid", and if he is observing it and taking appropriate evasive action, a
collision cannot occur.

Keep in mind that separation is not provided only by ATC traffic guidance
and "see and avoid", it's also provided by "east is odd, west is even, VFR
+500" altitudes and other things.


>
> --
> Peter
>
>
>
>
>

[Dan Girellini]

== Peter R > writes:

> Bill Denton ) wrote:
>> And I don't know if this is a trick question, but if you are at 6000 (no
>> +500) wouldn't you be on an IFR flight plan, talking to ATC, and receiving
>> traffic advisories?

> In the US and outside of class B airspace, it is the pilot, not ATC, who
> is ultimately responsible for IFR/VFR traffic separation. A VFR traffic
> advisory to an IFR aircraft is a courtesy offered by ATC; it is not a
> guarantee.

I thought Class C services included IFR/VFR separation. Is that old/wrong
information?

dan.

--
PGP key at http://www.longhands.org/drg-pgp.txt Key Id:0x507D93DF

[Bill Denton]

No, separation is not provided by ATC.




"Dan Girellini" > wrote in message
...
> == Peter R > writes:
>
> > Bill Denton ) wrote:
> >> And I don't know if this is a trick question, but if you are at 6000
(no
> >> +500) wouldn't you be on an IFR flight plan, talking to ATC, and
receiving
> >> traffic advisories?
>
> > In the US and outside of class B airspace, it is the pilot, not ATC,
who
> > is ultimately responsible for IFR/VFR traffic separation. A VFR
traffic
> > advisory to an IFR aircraft is a courtesy offered by ATC; it is not a
> > guarantee.
>
> I thought Class C services included IFR/VFR separation. Is that old/wrong
> information?
>
> dan.
>
> --
> PGP key at http://www.longhands.org/drg-pgp.txt Key Id:0x507D93DF

[Peter R.]

Bill Denton ) wrote:

> No, the orignal poster presented the scenario. I simply pointed out that a
> 6000 feet he would be on an IFR flight plan, talking to ATC, and receiving
> traffic from ATC.

6,000 feet guarantees an IFR flight plan? Really? You had better
notify the FAA about all those VFR pilots who fly around Denver, CO.

> You introduced the passage and misinterpreted it. I provided a correct
> interpretation.

OK, Bill, you win. Your string of non sequiturs throughout this portion
of the thread has worn me out. I have no idea what passage you think I
introduced, as in reality I didn't introduce any passage in this thread,
but nonetheless, you win. I didn't think you were a troll, since you
are a regular in this and other aviation forums, but your self-admitted
lack of any real aviation experience combined with your talent to post
with such authority and conviction now make me wonder.

--
Peter

[Peter R.]

Dan Girellini ) wrote:

> I thought Class C services included IFR/VFR separation. Is that old/wrong
> information?

Yes, in the US VFR aircraft will receive separation services in class C
airspace, but is this the same level of service as the guaranteed
separation offered by class B? It is my understanding that the two are
not equivalent.

Hopefully one of the controllers who frequents this group will provide a
better explanation.



--
Peter

[Dan Girellini]

== Bill Denton > writes:

> "Dan Girellini" > wrote in message

>> I thought Class C services included IFR/VFR separation. Is that old/wrong
>> information?

> No, separation is not provided by ATC.

Can you explain how I'm misinterpreting this from the AIM?

[3-2-4] Class C Airspace
....
e. Aircraft Separation. Separation is provided within the Class C airspace
and the outer area after two-way radio communications and radar contact
are established. VFR aircraft are separated from IFR aircraft within the
Class C airspace by any of the following:

1. Visual separation.

2. 500 feet vertical; except when operating beneath a heavy jet.

3. Target resolution.

--
PGP key at http://www.longhands.org/drg-pgp.txt Key Id:0x507D93DF

[Peter R.]

Dan Girellini ) wrote:

> I thought Class C services included IFR/VFR separation. Is that old/wrong
> information?

Yes, in the US VFR aircraft will receive separation services in class C
airspace, but is this the same level of service as the guaranteed
separation offered by class B? It is my understanding that the two are
not equivalent.

Hopefully one of the controllers who frequents this group will provide a
better explanation.



--
Peter

[Dan Girellini]

-- " " == Peter R > writes:

> Dan Girellini ) wrote:
>> I thought Class C services included IFR/VFR separation. Is that old/wrong
>> information?

> Yes, in the US VFR aircraft will receive separation services in class C
> airspace, but is this the same level of service as the guaranteed
> separation offered by class B? It is my understanding that the two are not
> equivalent.

What's in my Jepp text and afaict is confirmed in the AIM is that class C
provides only vfr/ifr separation whereas class B provides all acft separation
(ie vfr/vfr).

dan.

--
PGP key at http://www.longhands.org/drg-pgp.txt Key Id:0x507D93DF

[Newps]

Bill Denton wrote:

>>I am not sure what your point about VFR-on-top is, but as a reminder to
>>you, in the US VFR-on-TOP is a specific IFR clearance that must be
>>requested.
>
>
> And if you are granted that clearance, you will be flying under what are
> essentially Visual Flight Rules, you will be allowed to deviate from your
> as-filed flight plan,

No. You must follow the flight plan just as if you were regular IFR.
Slight deviations for cloud clearance are OK. If you want a different
route then you must ask for and receive a new clearance.

[Newps]

Bill Denton wrote:

> No, separation is not provided by ATC.

ATC provides separation between IFR and VFR aircraft within the class C.

[Newps]

Peter R. wrote:

> Dan Girellini ) wrote:
>
>
>>I thought Class C services included IFR/VFR separation. Is that old/wrong
>>information?
>
>
> Yes, in the US VFR aircraft will receive separation services in class C
> airspace, but is this the same level of service as the guaranteed
> separation offered by class B? It is my understanding that the two are
> not equivalent.
>

Well, it's not 1000 or 3 but you won't hit 'em.

[Bill Denton]

An even number of hundreds of feet is reserved for IFR flights (5,000 or
6,000). VFR flights must be +500 (5,500 or 6,000). If you see someone
breaking the rules by flying VFR at 6,000 feet you should report them; it's
your safety that's at stake.

This is not a matter of winning an losing, it's a matter of learning the
rules and assuring everyone's safety.

And it's not a matter of aviation experience or the lack thereof. Very few
ATC controllers actually know how to fly. But we all read the same AIM, and
while it can sometimes be confusing, if you look at things in the larger
context you can usually make sense out of it. And if that fails, you can
always phone or email your local FSDO with any questions (which I frequently
do), I've always gotten very prompt answers.

As far as my "talent to post with such authority and conviction" goes, I've
been a professional writer most of my life; that's the way professional
writers write. But just because I write with "authority and conviction"
doesn't mean I'm always right. And I've been married and divorced four
times; I had more arguments than any man needs. I'm certainly not looking
for another. I'm here to learn and contribute what I can; that's all.




"Peter R." > wrote in message
...
> Bill Denton ) wrote:
>
> > No, the orignal poster presented the scenario. I simply pointed out that
a
> > 6000 feet he would be on an IFR flight plan, talking to ATC, and
receiving
> > traffic from ATC.
>
> 6,000 feet guarantees an IFR flight plan? Really? You had better
> notify the FAA about all those VFR pilots who fly around Denver, CO.
>
> > You introduced the passage and misinterpreted it. I provided a correct
> > interpretation.
>
> OK, Bill, you win. Your string of non sequiturs throughout this portion
> of the thread has worn me out. I have no idea what passage you think I
> introduced, as in reality I didn't introduce any passage in this thread,
> but nonetheless, you win. I didn't think you were a troll, since you
> are a regular in this and other aviation forums, but your self-admitted
> lack of any real aviation experience combined with your talent to post
> with such authority and conviction now make me wonder.
>
> --
> Peter
>
>
>
>
>

[Bill Denton]

My mistake...I misread this. Sorry!




"Dan Girellini" > wrote in message
...
> == Bill Denton > writes:
>
> > "Dan Girellini" > wrote in message
>
> >> I thought Class C services included IFR/VFR separation. Is that
old/wrong
> >> information?
>
> > No, separation is not provided by ATC.
>
> Can you explain how I'm misinterpreting this from the AIM?
>
> [3-2-4] Class C Airspace
> ...
> e. Aircraft Separation. Separation is provided within the Class C
airspace
> and the outer area after two-way radio communications and radar
contact
> are established. VFR aircraft are separated from IFR aircraft
within the
> Class C airspace by any of the following:
>
> 1. Visual separation.
>
> 2. 500 feet vertical; except when operating beneath a heavy jet.
>
> 3. Target resolution.
>
> --
> PGP key at http://www.longhands.org/drg-pgp.txt Key Id:0x507D93DF

[Icebound]

"Bill Denton" > wrote in message
...
>I noticed the later posts referenced a set of "rules" for setting up the
> "error", but absent those, you are back to the same old game of chance.
> What's to prevent another pilot from picking a corresponding "error" that
> would still maintain the head-on courses?


Well, if *I* were choosing a *parallel offset*, it would always be to the
*right* of direct-track. Maybe the guy on the reciprocal track would think
to do the same.

>
> And I don't know if this is a trick question, but if you are at 6000 (no
> +500) wouldn't you be on an IFR flight plan, talking to ATC, and receiving
> traffic advisories?

Well, I don't do IFR, but if you wish, change the scenario to my westbound
Cessna at 6500. And we are all "looking out", but just at the time we
appear as dots in each others windshield, my wife drops a water bottle that
rolls under my feet, so I bend down to get it, and she watches me. He's
been in the cockpit for 3 hours, in cruise descent, and his kid in the back
seat is a little antsy, and he's just realized he needs to look up a
frequency in the Airports and Frequency guide, because its kind of smudged
on his chart; he didn't think he'd need it, but what the hell.

The question was not meant to be tricky, nor to suggest that I am going to
throw my A/P onto the GPS and read the newspaper, instead of looking out the
window. I am just wondering out loud if super-accurate GPS nav creates a
"reduced chance" of horizontal clearance, over previous nav methods, given
the usual weaknesses and foibles of human pilots.


>
>
>
>
> "Icebound" > wrote in message
> ...
>> In the "good old" VOR days, it must have been pretty difficult to fly
>> down
>> the centerline of an airway (or of any direct track).
>>
>> So an eastbound VFR/IFR aircraft descending from 7500/7000 to his
>> destination, was more than likely to avoid traffic... on the reciprocal
>> track passing him by at 6500 or 6000... by some significant horizontal
>> error-distance, even if they didn't see each other (big sky theory :-) ).
>>
>> GPS horizontal accuracy with WAAS is already in the order of magnitude of
> a
>> Cessna's wingspan, and some are talking about getting it down to mere
>> inches.
>>
>> So the question is: If my Westbound Cessna at 6000 feet (with the
> autopilot
>> keeping it happily on the GPS-track centerline) meets the descending
> Bonanza
>> on the reciprocal track between the same two airports (using a similar
>> GPS/a-p combo), there is a distinct possibility that the horizontal
>> clearance may be zero...
>>
>> ...so is there anything in the current crop of GPS and/or Autopilot
> systems
>> that allow me to maintain a small cross-track error of my choosing,
> without
>> actually entering off-navaid-off-airport waypoints? ...or do we care; am
>> I
>> overly concerned???
>>
>>
>>
>>
>>
>>
>>
>>
>
>

[Icebound]

"SelwayKid" > wrote in message
om...
> "Icebound" > wrote in message
> >...

>> In the "good old" VOR days, it must have been pretty difficult to fly
>> down
>> the centerline of an airway (or of any direct track).

....snip...

> As for being difficult to fly the VOR, it was/is no more difficult
> than flying a compass heading and holding it.....which many pilots
> seem unable to do anymore. They would prefer that electronic gadgets
> do their flying for them and no thoughts as to what happens when the
> electrodes take a vacation.


Never having flown a VOR course myself... I still doubt very much that any
two pilots (OR auto-pilots), flying reciprocal headings between two VORs,
would both be able to *simultaneously* hold a course to within 10 feet of
the centre-line for the whole course, considering the receiver errors and
that the VOR radial-signal *itself* probably varies more than that.

I could be wrong.

[Bill Denton]

"Cloud clearance" was what I was referring to; sorry for my lack of
clarity...




"Newps" > wrote in message
...
>
>
> Bill Denton wrote:
>
> >>I am not sure what your point about VFR-on-top is, but as a reminder to
> >>you, in the US VFR-on-TOP is a specific IFR clearance that must be
> >>requested.
> >
> >
> > And if you are granted that clearance, you will be flying under what are
> > essentially Visual Flight Rules, you will be allowed to deviate from
your
> > as-filed flight plan,
>
> No. You must follow the flight plan just as if you were regular IFR.
> Slight deviations for cloud clearance are OK. If you want a different
> route then you must ask for and receive a new clearance.
>
>

[Allen]

"Newps" > wrote in message
...
>
> No. You must follow the flight plan just as if you were regular IFR.
> Slight deviations for cloud clearance are OK. If you want a different
> route then you must ask for and receive a new clearance.
>

IFR "VFR on top" routing remains the same but you fly at VFR altitudes
(cardinal altitude plus 500) of your choice while remaining in VMC.

Allen

[Bill Denton]

The only time this would really be an issue would be if the other aircraft
were on an exact reciprocal course. And even if he used a corresponding
offset, he would still be 1,000 feet above or below you...



"Icebound" > wrote in message
...
>
> "Bill Denton" > wrote in message
> ...
> >I noticed the later posts referenced a set of "rules" for setting up the
> > "error", but absent those, you are back to the same old game of chance.
> > What's to prevent another pilot from picking a corresponding "error"
that
> > would still maintain the head-on courses?
>
>
> Well, if *I* were choosing a *parallel offset*, it would always be to the
> *right* of direct-track. Maybe the guy on the reciprocal track would
think
> to do the same.
>
> >
> > And I don't know if this is a trick question, but if you are at 6000 (no
> > +500) wouldn't you be on an IFR flight plan, talking to ATC, and
receiving
> > traffic advisories?
>
> Well, I don't do IFR, but if you wish, change the scenario to my westbound
> Cessna at 6500. And we are all "looking out", but just at the time we
> appear as dots in each others windshield, my wife drops a water bottle
that
> rolls under my feet, so I bend down to get it, and she watches me. He's
> been in the cockpit for 3 hours, in cruise descent, and his kid in the
back
> seat is a little antsy, and he's just realized he needs to look up a
> frequency in the Airports and Frequency guide, because its kind of smudged
> on his chart; he didn't think he'd need it, but what the hell.
>
> The question was not meant to be tricky, nor to suggest that I am going to
> throw my A/P onto the GPS and read the newspaper, instead of looking out
the
> window. I am just wondering out loud if super-accurate GPS nav creates a
> "reduced chance" of horizontal clearance, over previous nav methods, given
> the usual weaknesses and foibles of human pilots.
>
>
> >
> >
> >
> >
> > "Icebound" > wrote in message
> > ...
> >> In the "good old" VOR days, it must have been pretty difficult to fly
> >> down
> >> the centerline of an airway (or of any direct track).
> >>
> >> So an eastbound VFR/IFR aircraft descending from 7500/7000 to his
> >> destination, was more than likely to avoid traffic... on the reciprocal
> >> track passing him by at 6500 or 6000... by some significant horizontal
> >> error-distance, even if they didn't see each other (big sky theory
:-) ).
> >>
> >> GPS horizontal accuracy with WAAS is already in the order of magnitude
of
> > a
> >> Cessna's wingspan, and some are talking about getting it down to mere
> >> inches.
> >>
> >> So the question is: If my Westbound Cessna at 6000 feet (with the
> > autopilot
> >> keeping it happily on the GPS-track centerline) meets the descending
> > Bonanza
> >> on the reciprocal track between the same two airports (using a similar
> >> GPS/a-p combo), there is a distinct possibility that the horizontal
> >> clearance may be zero...
> >>
> >> ...so is there anything in the current crop of GPS and/or Autopilot
> > systems
> >> that allow me to maintain a small cross-track error of my choosing,
> > without
> >> actually entering off-navaid-off-airport waypoints? ...or do we care;
am
> >> I
> >> overly concerned???
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >
> >
>
>

[Newps]

Allen wrote:

> "Newps" > wrote in message
> ...
>
>>No. You must follow the flight plan just as if you were regular IFR.
>>Slight deviations for cloud clearance are OK. If you want a different
>>route then you must ask for and receive a new clearance.
>>
>
>
> IFR "VFR on top" routing remains the same but you fly at VFR altitudes
> (cardinal altitude plus 500) of your choice while remaining in VMC.

Like I said.

[Allen]

Allen wrote:
>
> >
> > IFR "VFR on top" routing remains the same but you fly at VFR altitudes
> > (cardinal altitude plus 500) of your choice while remaining in VMC.
>

"Newps" > wrote in message
...
> Like I said.
>

Yes, sorry, I was just trying to clarify that although it is an IFR
clearance you are flying at VFR altitudes. :)

Allen

[Blueskies]

> wrote in message ...
>
>
> Blueskies wrote:
>
>>
>>
>> At midcourse, add a waypoint offset to one side or the other by a couple of miles. The enroute time would be changed
>> minimally...
>
> But, that wouldn't be a parallel offset and would result in crossing the two end points precisely on course.
>
> Also, the offset should be much smaller than 2 miles for domestic airspace operations.
>
>

But the end points are where you want to be - one is where you started and one is where you are going. If you have a
system that does not have the parallel course function, then this would be a simple solution. If you want perfect, then
plot a course using multiple waypoints...PIC chooses....

[Peter Duniho]

"Bill Denton" > wrote in message
...
> An even number of hundreds of feet is reserved for IFR flights (5,000 or
> 6,000). VFR flights must be +500 (5,500 or 6,000). If you see someone
> breaking the rules by flying VFR at 6,000 feet you should report them;
> it's
> your safety that's at stake.

Cruising altitudes need only be observed when above 3000' AGL. There are
plenty of places in the US where 6000' is NOT 3000' AGL, including Denver
(which Peter specifically mentioned).

Feel free to report a VFR pilot flying near Denver at 6000' for violating
the cruising altitude rules, but I doubt you'll find anyone to take you
seriously.

> This is not a matter of winning an losing, it's a matter of learning the
> rules and assuring everyone's safety.

It sure seems like it's a matter of "winning an [sic] losing" to you. Your
original reply to the original poster made implication that, since the
aircraft at 6000' must be IFR (not even necessarily true, but for the sake
of argument let's grant that), the pilot would be receiving traffic
advisories and so didn't need to worry about aircraft climing through his
cruise altitude of 6000'.

Your implication was patently false, and your continued insistence on trying
to introduce new, unrelated topics to the discussion sure make it seem like
you've dug your heels in and are willing to do pretty much whatever it takes
to avoid admitting that you made a mistake in your original reply.

If it's not a matter of "winning an [sic] losing" to you, why so resistant
to admitting your mistake?

Pete

[Peter Duniho]

"Bill Denton" > wrote in message
...
> VFR-on-top:
> [Description snipped]

I know what VFR-on-top is. It's nice to see you know too. But so what? We
aren't talking about "VFR-on-top" (well, we weren't until YOU brought it
up).

> A pilot flying VFR is required to observe "see and avoid". One pilot
> observing "see and avoid" and taking appropriate evasive action can avoid
> a
> collision.

One day, when you've got a few more hours, you'll realize that you had
better not trust the other guy to do your "see and avoid" for you.

> If a VFR pilot is climbing/descending, it is his responsibility to avoid
> pilots above him or below him.

The IFR pilot cruising at 6000' is ALSO responsible for avoiding pilots
climbing or descending through his altitude.

> A pilot flying IFR under VMC who is not observing "see and avoid" is not a
> very smart pilot.

I agree. But if you feel that way, what is the point to all of your other
"contribution" to this thread?

For a professional writer, you sure seem to be having a big problem getting
your point across (whatever it happens to be).

Pete

[Peter Duniho]

"Icebound" > wrote in message
...
> [...]
> Never having flown a VOR course myself... I still doubt very much that any
> two pilots (OR auto-pilots), flying reciprocal headings between two VORs,
> would both be able to *simultaneously* hold a course to within 10 feet of
> the centre-line for the whole course, considering the receiver errors and
> that the VOR radial-signal *itself* probably varies more than that.
>
> I could be wrong.

You are wrong. :)

For two pilots to *intentionally* stay exactly on course center on a VOR
airway would be challenging, granted. But the airway provides an
"attractor" for airplanes, and inasmuch as the airplanes average toward the
center of the airway, eventually a couple will come along flying the exact
same distance from the actual airway (whether that's 0.0 miles off-center or
3.9 miles off-center).

Like I said before, it's happened to me on several occasions (getting close
enough to other aircraft on an airway to require evasive action, that is).
That's with me handflying. Using an autopilot, VOR navigation can
theoretically be VERY good, especially close to the station (within 10-20
miles).

GPS increases the chances of collision, by reducing the average error. But
the issue did already exist with VOR navigation. Keep in mind that GPS
error is still going to be on the order 10 to 30 meters or so, just from the
position information standpoint, and then on top of that you still have the
problem of the airplane being kept exactly at the intended position (even
with an autopilot, there's going to be some slop, and not all pilots are
using autopilots in conjunction with their GPS navigation).

The total error even in the GPS case can be much larger than the wingspan of
typical GA aircraft, and so the same kinds of factors that protect against
collisions when using VOR navigation also protect against collisions when
using GPS navigation (though to a lesser degree).

Pete

[Bill Denton]

This was my reply to the original poster:

And I don't know if this is a trick question, but if you are at 6000 (no
+500) wouldn't you be on an IFR flight plan, talking to ATC, and receiving
traffic advisories?

See that little squiggly thing with a dot under it at the end of the line?
That's called a "question mark". That means I was asking a question, not
that I "made implication", which is actually "implied", by the way.

Look around on the page today; I've made a couple of mistakes and readily
acknowledged them.

My response to Denver was incorrect, as you pointed out, and I readily
acknowledge it.

But I don't run around trying to pick arguments; I have much better things
to do with my life. Obviously, you don't...



"Peter Duniho" > wrote in message
...
> "Bill Denton" > wrote in message
> ...
> > An even number of hundreds of feet is reserved for IFR flights (5,000 or
> > 6,000). VFR flights must be +500 (5,500 or 6,000). If you see someone
> > breaking the rules by flying VFR at 6,000 feet you should report them;
> > it's
> > your safety that's at stake.
>
> Cruising altitudes need only be observed when above 3000' AGL. There are
> plenty of places in the US where 6000' is NOT 3000' AGL, including Denver
> (which Peter specifically mentioned).
>
> Feel free to report a VFR pilot flying near Denver at 6000' for violating
> the cruising altitude rules, but I doubt you'll find anyone to take you
> seriously.
>
> > This is not a matter of winning an losing, it's a matter of learning the
> > rules and assuring everyone's safety.
>
> It sure seems like it's a matter of "winning an [sic] losing" to you.
Your
> original reply to the original poster made implication that, since the
> aircraft at 6000' must be IFR (not even necessarily true, but for the sake
> of argument let's grant that), the pilot would be receiving traffic
> advisories and so didn't need to worry about aircraft climing through his
> cruise altitude of 6000'.
>
> Your implication was patently false, and your continued insistence on
trying
> to introduce new, unrelated topics to the discussion sure make it seem
like
> you've dug your heels in and are willing to do pretty much whatever it
takes
> to avoid admitting that you made a mistake in your original reply.
>
> If it's not a matter of "winning an [sic] losing" to you, why so resistant
> to admitting your mistake?
>
> Pete
>
>

[Peter Duniho]

"Bill Denton" > wrote in message
...
> This was my reply to the original poster:
>
> And I don't know if this is a trick question, but if you are at 6000 (no
> +500) wouldn't you be on an IFR flight plan, talking to ATC, and receiving
> traffic advisories?
>
> See that little squiggly thing with a dot under it at the end of the line?
> That's called a "question mark". That means I was asking a question, not
> that I "made implication"

The question implies that if you WERE "on an IFR flight plan, talking to
ATC, and receiving traffic advisories" that there's not an issue with
avoiding other airplanes.

Perhaps you'd like to start from the beginning and explain what the point of
that post was, if not to question whether an airplane in the originally
described scenario would need to worry about traffic avoidance?

In absence of any implication on your part, your reply appears to be
completely irrelevant and tangential, which confuses the reader (who expects
there to be some intended meaning).

Pete

[Bill Denton]

Someone named "Peter R." gave an interpretation of a section of the AIM;
4-4-10. IFR SEPARATION STANDARDS

I posted the text of that section; if you want to call that bringing
something up, be my guest. You're only looking for an argument anyway.

I said I was a professional writer; I in no way implied that you were a
competent reader.



"Peter Duniho" > wrote in message
...
> "Bill Denton" > wrote in message
> ...
> > VFR-on-top:
> > [Description snipped]
>
> I know what VFR-on-top is. It's nice to see you know too. But so what?
We
> aren't talking about "VFR-on-top" (well, we weren't until YOU brought it
> up).
>
> > A pilot flying VFR is required to observe "see and avoid". One pilot
> > observing "see and avoid" and taking appropriate evasive action can
avoid
> > a
> > collision.
>
> One day, when you've got a few more hours, you'll realize that you had
> better not trust the other guy to do your "see and avoid" for you.
>
> > If a VFR pilot is climbing/descending, it is his responsibility to avoid
> > pilots above him or below him.
>
> The IFR pilot cruising at 6000' is ALSO responsible for avoiding pilots
> climbing or descending through his altitude.
>
> > A pilot flying IFR under VMC who is not observing "see and avoid" is not
a
> > very smart pilot.
>
> I agree. But if you feel that way, what is the point to all of your other
> "contribution" to this thread?
>
> For a professional writer, you sure seem to be having a big problem
getting
> your point across (whatever it happens to be).
>
> Pete
>
>

[Peter Duniho]

"Bill Denton" > wrote in message
...
> Someone named "Peter R." gave an interpretation of a section of the AIM;
> 4-4-10. IFR SEPARATION STANDARDS
>
> I posted the text of that section; if you want to call that bringing
> something up, be my guest.

That section has nothing to do with "VFR-on-top".

> You're only looking for an argument anyway.

Ad hominem.

> I said I was a professional writer; I in no way implied that you were a
> competent reader.

Ad hominem.

[Bill Denton]

The question mark "implied" nothing; it directly indicated that I was asking
a question.

And if the conditions in my question were "true", you would not need to fly
an offset on a GPS course, despite GPS improved accuracy, any more than you
would need to fly an offset on a VOR course; traffic avoidance would be
handled by ATC.




"Peter Duniho" > wrote in message
...
> "Bill Denton" > wrote in message
> ...
> > This was my reply to the original poster:
> >
> > And I don't know if this is a trick question, but if you are at 6000 (no
> > +500) wouldn't you be on an IFR flight plan, talking to ATC, and
receiving
> > traffic advisories?
> >
> > See that little squiggly thing with a dot under it at the end of the
line?
> > That's called a "question mark". That means I was asking a question, not
> > that I "made implication"
>
> The question implies that if you WERE "on an IFR flight plan, talking to
> ATC, and receiving traffic advisories" that there's not an issue with
> avoiding other airplanes.
>
> Perhaps you'd like to start from the beginning and explain what the point
of
> that post was, if not to question whether an airplane in the originally
> described scenario would need to worry about traffic avoidance?
>
> In absence of any implication on your part, your reply appears to be
> completely irrelevant and tangential, which confuses the reader (who
expects
> there to be some intended meaning).
>
> Pete
>
>

[Bill Denton]

b. Separation will be provided (by ATC - my note) between all aircraft
operating on IFR flight plans except during that part of the flight (outside
of Class B airspace or a TRSA) being conducted on a VFR-on-top/VFR
conditions clearance. Under these conditions, ATC may issue traffic
advisories, but it is the sole responsibility of the pilot to be vigilant so
as to see and avoid other aircraft.

That's the section I posted. The third line down references VFR-on-top.

Reading is fundamental...



"Peter Duniho" > wrote in message
...
> "Bill Denton" > wrote in message
> ...
> > Someone named "Peter R." gave an interpretation of a section of the AIM;
> > 4-4-10. IFR SEPARATION STANDARDS
> >
> > I posted the text of that section; if you want to call that bringing
> > something up, be my guest.
>
> That section has nothing to do with "VFR-on-top".
>
> > You're only looking for an argument anyway.
>
> Ad hominem.
>
> > I said I was a professional writer; I in no way implied that you were a
> > competent reader.
>
> Ad hominem.
>
>

[Peter Clark]

On Thu, 18 Nov 2004 18:01:28 -0600, "Bill Denton"
> wrote:

>The question mark "implied" nothing; it directly indicated that I was asking
>a question.
>
>And if the conditions in my question were "true", you would not need to fly
>an offset on a GPS course, despite GPS improved accuracy, any more than you
>would need to fly an offset on a VOR course; traffic avoidance would be
>handled by ATC.

OK, say I'm on an IFR flight plan, VMC prevails, in Class E airspace
at 6000 feet, in VMC. A non-transponder/radio equipped aircraft is
climbing from an airport, crossing my path up to their desired cruise
altitude of 6500 feet. Might I ask how ATC would provide me traffic
avoidance in that instance?

[Jim Harper]

wrote in message >...

>
> SLOP is approved for oceanic. Do you know if it is approved for non-radar environments of the USA? If so, what
> are the numbers to use? How do I determine when I am in a non-radar environment in the USA?

As a previous poster posted, you are in a non-radar environment when
you hear "radar contact lost". You are also in a non-radar environment
when you see mandatory reporting points. I believe that this mostly
applies to the great wide West.

No, SLOP does NOT apply, nor is it approved for the USA non-radar
environments. You are expected to fly right down the middle of the
airway.

Now, with respect to the ongoing argument about will/can you run into
someone on an IFR flightplan? Sure you can. I have always been
informed of traffic that the controllers see, so they _are_ trying to
tell us about VFR traffic.

Tell all your pilot friends...if you are going to fly VFR, especially
in IMC do NOT fly on airways. If you are flying IFR and you can do so,
file direct. It's a HUGE sky out there, and the airway and waypoint
system just funnels all of the traffic (which is using it) into a very
small portion of that huge sky. If I am not on an airway, I suspect
that the chances of hazarding upon some fool flying VFR in the clouds
are so small as to be non-existant. How often has it happened (hint,
try zero)? If I am flying IFR in VMC, I have my head out of the
cockpit and on a swivel. And in my (admittedly small) experince, the
controllers are in there pitching and telling me about traffic.

In any of these scenarios, does cross-track offset help? Nah, not
really.

Jim

[Judah]

"Bill Denton" > wrote in
:

>
> "Peter R." > wrote in message
> ...
>> Bill Denton ) wrote:
>>
>> > And I don't know if this is a trick question, but if you are at 6000
>> > (no +500) wouldn't you be on an IFR flight plan, talking to ATC, and
>> > receiving traffic advisories?
>>
>> In the US and outside of class B airspace, it is the pilot, not ATC,
>> who is ultimately responsible for IFR/VFR traffic separation. A VFR
>> traffic advisory to an IFR aircraft is a courtesy offered by ATC; it
>> is not a guarantee.
>>
>> --
>> Peter
>>
> You might want to rethink your reply.
>
> A pilot in clouds or other IMC cannot provide separation to any traffic
> he cannot see.
>
>

Neither can ATC - for example, when there is no Radar Coverage.

The system is designed to work even in those conditions, and the rules
follow suit...

In VMC, ALL pilots are required to "see and avoid", VFR or IFR.

VFR pilots are supposed to stay out of IMC to prevent getting hit by IFR
pilots on IFR flight plans in the IMC.

When there is no Radar, IFR separation is done using spacing and reporting
points. There are no traffic advisories, IFR or VFR.

VFR-to-IFR separation is a courtesy, as Peter said. If ATC calls out a
target to an IFR flight, and they are not talking to the VFR target too,
they can't even provide instructions that guarantee safe avoidance...


Don't take your advisories for granted. They are a favor.

[Peter Duniho]

"Bill Denton" > wrote in message
...
> The question mark "implied" nothing; it directly indicated that I was
> asking
> a question.

Fine. As hard as it is to imagine, let's grant your claim regarding the
lack of an implication. Then the answer to your question is "yes, assuming
you're also above 3000' AGL, but so what?" Emphasis on "so what?"

Given that there was no implication intended, what in the world was the
point of your original reply?

> And if the conditions in my question were "true", you would not need to
> fly
> an offset on a GPS course, despite GPS improved accuracy, any more than
> you
> would need to fly an offset on a VOR course; traffic avoidance would be
> handled by ATC.

In other words, you WOULD "need" to fly an offset, in order to ensure no
conflict with other traffic. There is a very real risk of a collision when
flying an airway, whether you're using GPS or VOR navigation. In practice,
we as pilots generally choose looking out the window over offsetting our
course, but the "need" is there nevertheless.

You continue to claim (just as your first post implied) that ATC handles
traffic avoidance for IFR flights, but that's simply not true. ATC only
separates IFR flights from other IFR flights (except in particular kinds of
airspace where VFR flights are also given traffic separation...a very small
portion of the national airspace system).

Pete

[Peter Duniho]

"Bill Denton" > wrote in message
...
> [snip]
>
> That's the section I posted. The third line down references VFR-on-top.

So, now you are agreeing that it was you that brought up VFR-on-top? As
irrelevant as it is to this thread, you are the person who introduced it.
By your own admission.

[Bill Denton]

This thread has gotten so long, I including my original reply to ensure that
we are on the same page:

I noticed the later posts referenced a set of "rules" for setting up the
"error", but absent those, you are back to the same old game of chance.
What's to prevent another pilot from picking a corresponding "error" that
would still maintain the head-on courses?

And I don't know if this is a trick question, but if you are at 6000 (no
+500) wouldn't you be on an IFR flight plan, talking to ATC, and receiving
traffic advisories?

My comments are in the text...4


"Peter Duniho" > wrote in message
...
> "Bill Denton" > wrote in message
> ...
> > The question mark "implied" nothing; it directly indicated that I was
> > asking
> > a question.
>
> Fine. As hard as it is to imagine, let's grant your claim regarding the
> lack of an implication. Then the answer to your question is "yes,
assuming
> you're also above 3000' AGL, but so what?" Emphasis on "so what?"
>
> Given that there was no implication intended, what in the world was the
> point of your original reply?
>
> > And if the conditions in my question were "true", you would not need to
> > fly
> > an offset on a GPS course, despite GPS improved accuracy, any more than
> > you
> > would need to fly an offset on a VOR course; traffic avoidance would be
> > handled by ATC.
>
> In other words, you WOULD "need" to fly an offset, in order to ensure no
> conflict with other traffic. There is a very real risk of a collision
when
> flying an airway, whether you're using GPS or VOR navigation. In
practice,
> we as pilots generally choose looking out the window over offsetting our
> course, but the "need" is there nevertheless.

As you will note from my original reply, the point was that if everyone is
randomly choosing their own offset, you aren't really improving your odds of
avoiding a head-on very much. You would probably be better off just flying
the centerline; at least you would know where to look for other traffic.


>
> You continue to claim (just as your first post implied) that ATC handles
> traffic avoidance for IFR flights, but that's simply not true. ATC only
> separates IFR flights from other IFR flights (except in particular kinds
of
> airspace where VFR flights are also given traffic separation...a very
small
> portion of the national airspace system).

Aircraft operate under the same traffic principles as automobiles: There is
a set of rules. If everyone follows the rules, no problem. But is someone
breaks the rules, you have a strong potential for a problem.

If you are IFR in IMC you probably will not be able to use "see and avoid".
You simply cannot see through the clouds/rain/whatever. You have to look to
ATC for separation, which they will provide for all aircraft on IFR flight
plans. Aircraft flying under VFR are not supposed to be in IMC. If they are,
that's a violation of the rules. And VFR and IFR aircraft are supposed to
maintain a 500 foot vertical separtaion above 3000 feet AGL. If the
separtion is not maintained, that's a violation of the rules. And when you
have a violation of the rules, the accident risk increases.

FAR 91.113 (c) mandates that when weather condtions permit, all aircraft,
whether flying VFR or IFR, must observe "see and avoid".

To sum it up, if you are IFR in IMC, you have to rely on ATC to separate you
from other IFR traffic; there should not be any VFR traffic there. If you
are in VMC, whether VFR or IFR, you must observe "see and avoid". And all
aircraft must maintain the 500 foot separation between VFR and IFR aircraft.

Obviously, when aircraft are ascending or descending, the risk of collision
increases. But you can only rely on ATC in IMC to reduce this risk, or use
"see and avoid" in VMC.

And I am aware that there are other IFR separation methods such as takeoff
sequencing and timing, maintaining separation via speed, flying your flight
plan exactly if something goes wrong, and similar methods, but they aren't
really germane to this limited discussion.




>
> Pete
>
>

[Bill Denton]

No, I am not agreeing to anything. I will state that I was the first to
introduce the words VFR-on-top into the thread, while quoting a section of
the AIM.

The AIM states that ATC will provide IFR/IFR separation. But, a VFR-on-fop
flight is an IFR flight, and ATC does not provide separation to VFR-on-top
aircraft. We were discussing IFR separation and this is a part of them, so
it is relevant to the thread.



"Peter Duniho" > wrote in message
...
> "Bill Denton" > wrote in message
> ...
> > [snip]
> >
> > That's the section I posted. The third line down references VFR-on-top.
>
> So, now you are agreeing that it was you that brought up VFR-on-top? As
> irrelevant as it is to this thread, you are the person who introduced it.
> By your own admission.
>
>

[Gene Whitt]

Y'All,
This entire thread seems to be totally entranced with the possible conflict
of aircraft on a heading/course. Whereas, the most likely conflict is in
altitude between IFR and VFR supposedly flying with 500 feet of FAA
separation.

Some time ago I was told that ATC figures a + - error 300 feet.
The altimeter is likewise allowed a 75 foot + - error. Not knowing for
certain but assuming it is so. Look at the following senario.

If we have an IFR and a VFR fllying in opposite hemisphereic directions in
VFR conditions we have several possible extreme conditions. Take the first
aircraft indicating 6000 feet west bound. The second aircraft indicating
5500 feet east bound. If both the transponders and altimeters have errors
to the extreme in the opposite directions, they could still miss each other.

If the first aircraft is flying 250 lower than indicated due to accumulated
instrment error, while the other is actually flying 250 feet higher than
indicated we have only see and be seen to save the situation.

To me the probability of a midair is more likely to altitude error than
heading error. The odds of having two such aircraft with hemispheric
accumulative opposite errors in altitude sufficient to cause a midair is
unlikely but more likely than an opposite heading midair. I believe this
because the distances are matters of feet rather than miles. It takes both
to actually cause the midair.so the total emphasis on course/heading is only
a part of the equation.

I haven't even mentioned GPS altitude as a factor.
Mud wrestling anyone?

Gene

[Icebound]

"Gene Whitt" > wrote in message
link.net...
> Y'All,
> This entire thread seems to be totally entranced with the possible
> conflict of aircraft on a heading/course. Whereas, the most likely
> conflict is in altitude between IFR and VFR supposedly flying with 500
> feet of FAA separation.
> ...snip...
> To me the probability of a midair is more likely to altitude error than
> heading error. The odds of having two such aircraft with hemispheric
> accumulative opposite errors in altitude sufficient to cause a midair is
> unlikely but more likely than an opposite heading midair. .


Actually, if the two of them are not on the exact same location
horizontally, the odds of a conflict because of altitude error is zero.

While there is some remote possibility of being in the same location
horizontally at the same time while crossing tracks, the potential to be in
the same location horizontally is much greater when they are navigating
reciprocal tracks between the same two waypoints.

[Icebound]

"Peter Duniho" > wrote in message
...
> "Icebound" > wrote in message
> ...
>> [...]
>> Never having flown a VOR course myself... I still doubt very much that
>> any two pilots (OR auto-pilots), flying reciprocal headings between two
>> VORs, would both be able to *simultaneously* hold a course to within 10
>> feet of the centre-line for the whole course, considering the receiver
>> errors and that the VOR radial-signal *itself* probably varies more than
>> that.
>>
>> I could be wrong.
>
> You are wrong. :)
>
> For two pilots to *intentionally* stay exactly on course center on a VOR
> airway would be challenging, granted. But the airway provides an
> "attractor" for airplanes, and inasmuch as the airplanes average toward
> the center of the airway, eventually a couple will come along flying the
> exact same distance from the actual airway (whether that's 0.0 miles
> off-center or 3.9 miles off-center).

Accepted and agreed. "eventually".

But in the GPS case, it is pretty much in "every" case that two aircraft
using those two waypoints will be pretty much in the center.

[Peter Duniho]

"Bill Denton" > wrote in message
...
> [...] We were discussing IFR separation

No, we weren't. YOU turned it into that discussion, but nothing about the
original post had anything to do with IFR separation.

That is, in fact, the entire point of this monster subthread you've
inspired.

[Peter Duniho]

"Icebound" > wrote in message
...
> But in the GPS case, it is pretty much in "every" case that two aircraft
> using those two waypoints will be pretty much in the center.

But "pretty much" still covers quite a bit of ground. There is only an
increased risk of a collision, not a virtual certainty.

[[email protected]]

Jim Harper wrote:

> wrote in message >...
>
>
>
> As a previous poster posted, you are in a non-radar environment when
> you hear "radar contact lost". You are also in a non-radar environment
> when you see mandatory reporting points. I believe that this mostly
> applies to the great wide West.

When flying at, or near MEA in the great wide West there are lots of radar holes where ATC doesn't bother to terminate
radar because you will reappear in 10 or 15 minutes. So, they say nothing.

As to the remainder of your concern TCAS has gone a long ways to solving the en route problem of midair potential for
airliners and biz jets. That is the real solution for everyone. It should be a higher priority for light aircraft.

[Icebound]

"Peter Duniho" > wrote in message
...
> "Icebound" > wrote in message
> ...
>> But in the GPS case, it is pretty much in "every" case that two aircraft
>> using those two waypoints will be pretty much in the center.
>
> But "pretty much" still covers quite a bit of ground. There is only an
> increased risk of a collision, not a virtual certainty.
>

Oh, for sure.

[SelwayKid]

"Icebound" > wrote in message >...
> "SelwayKid" > wrote in message
> om...
> > "Icebound" > wrote in message
> > >...
>
> >> In the "good old" VOR days, it must have been pretty difficult to fly
> >> down
> >> the centerline of an airway (or of any direct track).
>
> ...snip...
>
> > As for being difficult to fly the VOR, it was/is no more difficult
> > than flying a compass heading and holding it.....which many pilots
> > seem unable to do anymore. They would prefer that electronic gadgets
> > do their flying for them and no thoughts as to what happens when the
> > electrodes take a vacation.
>
>
> Never having flown a VOR course myself... I still doubt very much that any
> two pilots (OR auto-pilots), flying reciprocal headings between two VORs,
> would both be able to *simultaneously* hold a course to within 10 feet of
> the centre-line for the whole course, considering the receiver errors and
> that the VOR radial-signal *itself* probably varies more than that.
>
> I could be wrong.
*********************
Icebound
If you have never flown a VOR course, where in hell do you fly? And,
if you have never flown a VOR course, what do you know about them or
what their capabilities are? Part of the PTS for every US rating
involves VOR.
Beyond that, let me ask if you are a licensed pilot? Hmmm, well you
may be in another country, perhaps 3rd world without VOR but even
then, of the 26 countries I've worked in, all had VOR coverage of some
kind. So again, where do you fly?
Ol Shy & Bashful

[OtisWinslow]

Your exactly right and the use of parallel track will help that. Offset to
the right a
bit.


"Icebound" > wrote in message
...
> In the "good old" VOR days, it must have been pretty difficult to fly down
> the centerline of an airway (or of any direct track).
>
> So an eastbound VFR/IFR aircraft descending from 7500/7000 to his
> destination, was more than likely to avoid traffic... on the reciprocal
> track passing him by at 6500 or 6000... by some significant horizontal
> error-distance, even if they didn't see each other (big sky theory :-) ).
>
> GPS horizontal accuracy with WAAS is already in the order of magnitude of
> a Cessna's wingspan, and some are talking about getting it down to mere
> inches.
>
> So the question is: If my Westbound Cessna at 6000 feet (with the
> autopilot keeping it happily on the GPS-track centerline) meets the
> descending Bonanza on the reciprocal track between the same two airports
> (using a similar GPS/a-p combo), there is a distinct possibility that the
> horizontal clearance may be zero...
>
> ...so is there anything in the current crop of GPS and/or Autopilot
> systems that allow me to maintain a small cross-track error of my
> choosing, without actually entering off-navaid-off-airport waypoints?
> ...or do we care; am I overly concerned???
>
>
>
>
>
>
>
>

[Dean Wilkinson]

"Gene Whitt" > wrote in message . net>...
> Y'All,
> This entire thread seems to be totally entranced with the possible conflict
> of aircraft on a heading/course. Whereas, the most likely conflict is in
> altitude between IFR and VFR supposedly flying with 500 feet of FAA
> separation.
>
> Some time ago I was told that ATC figures a + - error 300 feet.
> The altimeter is likewise allowed a 75 foot + - error. Not knowing for
> certain but assuming it is so. Look at the following senario.
>
> If we have an IFR and a VFR fllying in opposite hemisphereic directions in
> VFR conditions we have several possible extreme conditions. Take the first
> aircraft indicating 6000 feet west bound. The second aircraft indicating
> 5500 feet east bound. If both the transponders and altimeters have errors
> to the extreme in the opposite directions, they could still miss each other.
>
> If the first aircraft is flying 250 lower than indicated due to accumulated
> instrment error, while the other is actually flying 250 feet higher than
> indicated we have only see and be seen to save the situation.
>
> To me the probability of a midair is more likely to altitude error than
> heading error. The odds of having two such aircraft with hemispheric
> accumulative opposite errors in altitude sufficient to cause a midair is
> unlikely but more likely than an opposite heading midair. I believe this
> because the distances are matters of feet rather than miles. It takes both
> to actually cause the midair.so the total emphasis on course/heading is only
> a part of the equation.
>
> I haven't even mentioned GPS altitude as a factor.
> Mud wrestling anyone?
>
> Gene

Excellent point Gene. This is why maintaining a good visual scan is
important, and why TCAS and TCAD systems are so valuable. I wish that
we were at the point where every airplane equipped with a transponder
also had a TCAS or TCAD system installed. It would be nice if this
equipment were affordable enough to do this.

Dean

[Icebound]

"SelwayKid" > wrote in message
om...
> "Icebound" > wrote in message
> >...
>> "SelwayKid" > wrote in message
>> om...
>> > "Icebound" > wrote in message
>> > >...
>>
>> >> In the "good old" VOR days, it must have been pretty difficult to fly
>> >> down
>> >> the centerline of an airway (or of any direct track).
>>
>> ...snip...
>>
>> > As for being difficult to fly the VOR, it was/is no more difficult
>> > than flying a compass heading and holding it.....which many pilots
>> > seem unable to do anymore. They would prefer that electronic gadgets
>> > do their flying for them and no thoughts as to what happens when the
>> > electrodes take a vacation.
>>
>>
>> Never having flown a VOR course myself... ...snip...
>>
>> I could be wrong.



> *********************
> Icebound
> If you have never flown a VOR course, where in hell do you fly? .... So
> again, where do you fly?

Hey, I never said that I flew at all. yet. I don't think that disqualifies
me from trying to clarify some stuff for the day that I might :-)

Inspire me. Educate me. Convince me that a VOR course can be held to the
same 10 metre tolerance over 100 NM miles, that it appears a GPS course can.
(Without the GPS in the cockpit for reference, of course.)

[Cub Driver]

>If you have never flown a VOR course, where in hell do you fly?

I am a certificated American pilot, and have been for six years. I
have never flown a VOR course and never expect to. I fly in New
Hampshire, Maine, and Massachusetts. I have about 350 hours.

(Early on, I owned a Sporty's handheld with nav feature. I once tuned
it to the Pease VOR just to see how it worked, and never used the
feature again. After not very long, I got rid of the Sporty's for a
Yaseu/Vertex without the nav feature, and have never regretted it. If
I need an electronic aid, I use the GPS. Indeed, if it's comfortable
to do so, I avoid VORs on the theory that they must be airplane
magnets. To a lesser extent, the same must be true of VOR courses,
depending on one's distance from the VOR. Who needs places where other
airplanes congregate?)


all the best -- Dan Ford
email: (put Cubdriver in subject line)

Warbird's Forum www.warbirdforum.com
Piper Cub Forum www.pipercubforum.com
the blog www.danford.net

[[email protected]]

Bill Denton wrote:

> I noticed the later posts referenced a set of "rules" for setting up the
> "error", but absent those, you are back to the same old game of chance.
> What's to prevent another pilot from picking a corresponding "error" that
> would still maintain the head-on courses?
>

Presumably, they would both offset to the right, and I think the greatest
concern is about opposite direction traffic.

[Peter R.]

Cub Driver ) wrote:

> I am a certificated American pilot, and have been for six years. I
> have never flown a VOR course and never expect to. I fly in New
> Hampshire, Maine, and Massachusetts. I have about 350 hours.

Is this VFR or IFR?

I mainly file and fly IFR in the Northeast US and I have learned that if
I am flying to or from Boston or anywhere near NYC, I must file and at
least start flying airways. The controllers will offer direct where
possible, but the volume of traffic during the peak hours often prevents
this.

In my experience, there have been a few times where the only way I could
get off the airways was to cancel IFR, weather depending.

--
Peter

[Tim Hogard]

Peter Duniho ) wrote:
: GPS increases the chances of collision, by reducing the average error. But
: the issue did already exist with VOR navigation. Keep in mind that GPS
: error is still going to be on the order 10 to 30 meters or so, just from the
: position information standpoint, and then on top of that you still have the
: problem of the airplane being kept exactly at the intended position (even
: with an autopilot, there's going to be some slop, and not all pilots are
: using autopilots in conjunction with their GPS navigation).

The GPS error you have quoted is relative to a fixed point on the ground.
Most modern cheap GPS recievers in the same region looking at the same
sats with differential corrections are within meters of each other
and with good processing can produce a relative position within a few
inches.

The way to deal with this is to simply move the GPS course .1 nmi
to the right. This means if your doing a 90 degree turn over a VOR
using a GPS, you should make your turn .14 nmi away from the VOR
and you should be able to see it out the left window.

At this point it won't matter much considering the GA autopilot slop
but things could change in the future and now is a good time to
start putting these things in place.

but there are more an more aircraft flying in the skys that don't
but things could change in the future and now is a good time to
start putting these things in place.

-tim
http://web.abnormal.com

[Gene Whitt]

Y'All,
To those of you who view this offset GPS program as the latest, I
would like to add the following.

At near the end of WWII when I was a 21-year old Corporal I was
the operator/mechanic of a radar bombardment simulator/trainer as a part of
the 58th Bomb Wing Training Center (B-29) on Tinian
The device was called the Supersonic Trainer and made possible simulations
of actual bombardment runs over Japan. In the week or so prior to the
dropping of the bombs I was told to put the Nagasaki
map into the Trainer.

The trainer was running in conjunction with the APQ-23 radar system. This
was the most advanced radar bombardment system of the war and was still the
standard over five years later. Among its capabiities was to program offset
bombing.. By dialing in the azmuth and distance of a target from a radar
visible target such as a lake we could fly as though bombing the lake but
hit the target. This is where
all the offset navigation came from.

Incidentally the Nagasaki bomb missed its aiming point by three miles. If
you want the full story go to my web site at the very end
of the IFR section. 7.9++ www.whittsflying.com
Gene Whitt