ATC assigned altitude?

[Tina]

It used to be that when we were assigned an en route altitude we held
it, plus or minus a needle width or so -- husbands trained as
engineers are apt to be a little compulsive about things like that.
Well, we had a long discussion with another pilot who had different
advice. He suggested, since we are in a low winged airplane, we hold
assigned less 50 feet or so -- if a high winged airplane, he'd have
recommended assigned plus 50. His obvious intent is to avoid en route
conflicts. It seems like a cheap insurance policy to me, but how real
is the threat? Does anyone have an idea on how often there are
altitude conflicts when on an IFR flight plan?

We have agreed on VFR cross country flights (something that we very
rarely do) we will hold that kind of offset to the altitude rule as a
matter of routine: you might consider doing that too.

[Harry[_2_]]

"Tina" > wrote in message
...
><snip>
> We have agreed on VFR cross country flights (something that we very
> rarely do) we will hold that kind of offset to the altitude rule as a
> matter of routine: you might consider doing that too.

Why? I'm sorry but I've never heard of this practice and it seems to me that
if everyone did it, what would be the difference of doing what you're
suggesting as opposed to sticking with the X-thousand + 500 feet (VFR)????

I'm not trying to be argumentative - just wondering...

Harry
PP-ASEL
VFR only

[Bob Noel]

In article >,
Tina > wrote:

> We have agreed on VFR cross country flights (something that we very
> rarely do) we will hold that kind of offset to the altitude rule as a
> matter of routine: you might consider doing that too.

That's a great way to use up a significant chunk of the error budget.
(error budgets being something engineers should understand).

--
Bob Noel
(goodness, please trim replies!!!)

[Tina]

Bob, we fully appreciate error budgets and propagation of errors
analysis. Never the less if most VFR traffic is 'trying' to fly at
the correct hemispheric altitude (especially those who tend to fly as
high as reasonable) , and we bias our choice of altitude to be under
the mean altitude of the others, we will probably have reduced an
already small risk to one even smaIller.

I don't don't know the statistics for altitude holding accuracy in the
less than 12000 feet VFR XC world, but would not be surprised if the
S. D. is the order of 50 or 80 feet.

I also don't know the stats on near misses (or worse) during the
cruise phase of VFR XC but am trying to find out. Near misses are
going to be very much under reported, aren't they?

I've offered an argument for not staying at the exact altitude during
VFR XC , and am interested in learning some reasonable rebuttals. I
did offer one for not maintaining the exact expected altitude and hope
someone can offer compelling reasonings as to why those reasons are
not valid.

[Larry Dighera]

On Sun, 18 May 2008 14:30:55 -0400, Bob Noel
> wrote in
>:

>That's a great way to use up a significant chunk of the error budget.

That was my first thought too.

However, it also brought to mind a somewhat tense situation I
experienced while VFR transiting over KLAX via the Special Flight
Rules Area: http://skyvector.com/#35-24-3-2785-2374

The ledged for the LAXSFRA is on the VFR Terminal chart (accessible by
clicking the Charts icon at the top of the page at that link above),
and basically indicates that SE bound flights cross over the KLAX
runways at 3,500' and NW bound flights at 4,500' squawking 1201 and
communicating air-to-air on 128.55 MHz with periodic self announced
position reports. ATC is not involved.

I was flying a low-wing, and announced my position as over the
southern boundary of the field, and immediately subsequent a Cessna
reported being at the same position and altitude. I wanted to take
evasive action, but without the Cessna in sight, there was no good way
of knowing exactly what that might be. I announced again, and so did
the Cessna, but we did not sight each other. The atmosphere got more
tense as the moments ticked by, and I kept expecting the sounds of
impact at any second. I considered maneuvering again, but finally
decided, that currently I was okay, and doing nothing would likely not
change that.

I suppose I could have assumed that the Cessna was below me, and
climbed a 100', but I didn't.

[Capt. Geoffrey Thorpe]

"Larry Dighera" > wrote in message
...
> On Sun, 18 May 2008 14:30:55 -0400, Bob Noel
> > wrote in
> >:
><...>
> I was flying a low-wing, and announced my position as over the
> southern boundary of the field, and immediately subsequent a Cessna
> reported being at the same position and altitude. I wanted to take
> evasive action, but without the Cessna in sight, there was no good way
> of knowing exactly what that might be. I announced again, and so did
> the Cessna, but we did not sight each other. The atmosphere got more
> tense as the moments ticked by, and I kept expecting the sounds of
> impact at any second. I considered maneuvering again, but finally
> decided, that currently I was okay, and doing nothing would likely not
> change that.

http://wingsandwheels.com/page4.htm

--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.

[Larry Dighera]

On Sun, 18 May 2008 20:33:45 -0400, "Capt. Geoffrey Thorpe" <The Sea
Hawk At Wow Way D0t C0m> wrote in
>:

>"Larry Dighera" > wrote in message
...
>> On Sun, 18 May 2008 14:30:55 -0400, Bob Noel
>> > wrote in
>> >:
>><...>
>> I was flying a low-wing, and announced my position as over the
>> southern boundary of the field, and immediately subsequent a Cessna
>> reported being at the same position and altitude. I wanted to take
>> evasive action, but without the Cessna in sight, there was no good way
>> of knowing exactly what that might be. I announced again, and so did
>> the Cessna, but we did not sight each other. The atmosphere got more
>> tense as the moments ticked by, and I kept expecting the sounds of
>> impact at any second. I considered maneuvering again, but finally
>> decided, that currently I was okay, and doing nothing would likely not
>> change that.
>
>http://wingsandwheels.com/page4.htm

That's an interesting device. I'm not sure it would have been too
useful in the case cited above. The vertical resolution isn't going
to be better than the +/- 100' of Mode C, and it's not clear that it
can resolve the lateral position of aircraft in close proximity; it
appears to just go into alarm when one gets closer that the preset
distance selected. It may have been useful when our two aircraft were
more distant and converging however. Thanks for the information.

[Mxsmanic]

Larry Dighera writes:

> I considered maneuvering again, but finally
> decided, that currently I was okay, and doing nothing would likely not
> change that.

You did the logical thing. If you and the other aircraft had indeed been in
exactly the same position, you would have already collided. Obviously you
were not in exactly the same position. And without knowing the actual, exact
position of the other aircraft, a sudden departure from your steady, level
flight would make no sense. Which way would you go? How would you know that
you were flying away from the other aircraft, and not towards it? You would
have about a 50/50 chance.

> I suppose I could have assumed that the Cessna was below me, and
> climbed a 100', but I didn't.

And had you climbed and the Cessna been above you, that would be the end of
it.

[Benjamin Dover]

Mxsmanic > wrote in
:

> Larry Dighera writes:
>
>> I considered maneuvering again, but finally
>> decided, that currently I was okay, and doing nothing would likely
>> not change that.
>
> You did the logical thing. If you and the other aircraft had indeed
> been in exactly the same position, you would have already collided.
> Obviously you were not in exactly the same position. And without
> knowing the actual, exact position of the other aircraft, a sudden
> departure from your steady, level flight would make no sense. Which
> way would you go? How would you know that you were flying away from
> the other aircraft, and not towards it? You would have about a 50/50
> chance.
>
>> I suppose I could have assumed that the Cessna was below me, and
>> climbed a 100', but I didn't.
>
> And had you climbed and the Cessna been above you, that would be the
> end of it.
>

If you had ever sat in a real Piper or a real Cessna, you would know that
it is safer for the Piper to climb than to descend. It is not a 50/50
proposition. But you don't fly and you're a moron.

[Mxsmanic]

Benjamin Dover writes:

> If you had ever sat in a real Piper or a real Cessna, you would know that
> it is safer for the Piper to climb than to descend.

Neither is safe if you do not have visual contact with the other traffic.

If neither aircraft has visual contact with the other, and no other
information is available, neither aircraft should take any special action. If
visual contact is available, the pilot(s) with contact should see and avoid.
If no visual contact has been made by either pilot, but one or both pilots has
other reliable sources of information allowing the aircraft to determine their
positions relative to each other, those sources can be used to determine what
action, if any, should be taken.

In this situation, it might help to share information on airspeed or DME from
the LAX VOR, either of which might help to locate the aircraft in relation to
each other. I suggest LAX because it's almost at right angles to the SFRA
route, whereas SMO would see both aircraft one behind the other. Of course,
if they are very close, DME might not be reliable.

I've wondered in the past exactly how aircraft coordinate their movements in
the SFRA, since the corridor in each direction is extremely narrow.

[Benjamin Dover]

Mxsmanic > wrote in
:

> Benjamin Dover writes:
>
>> If you had ever sat in a real Piper or a real Cessna, you would know
>> that it is safer for the Piper to climb than to descend.
>
> Neither is safe if you do not have visual contact with the other
> traffic.
>
> If neither aircraft has visual contact with the other, and no other
> information is available, neither aircraft should take any special
> action. If visual contact is available, the pilot(s) with contact
> should see and avoid. If no visual contact has been made by either
> pilot, but one or both pilots has other reliable sources of
> information allowing the aircraft to determine their positions
> relative to each other, those sources can be used to determine what
> action, if any, should be taken.
>
> In this situation, it might help to share information on airspeed or
> DME from the LAX VOR, either of which might help to locate the
> aircraft in relation to each other. I suggest LAX because it's almost
> at right angles to the SFRA route, whereas SMO would see both aircraft
> one behind the other. Of course, if they are very close, DME might
> not be reliable.
>
> I've wondered in the past exactly how aircraft coordinate their
> movements in the SFRA, since the corridor in each direction is
> extremely narrow.
>

As previouls stated, had you ever sat in a real Piper and a real Cessna,
you would know that a climb in the Piper is not a 50/50 guess. But you
haven't and moronically continue to spout bull****.

You don't know **** from shinola.

[Tina]

Do you think in a conventional high wing Cessna vs a conventional low
wing airplane, (thinking horses here, not zebras here) since low wings
tend to cruise a bit faster, it would have been prudent to increase
airspeed to the maximum available and accelerate away from the threat?

The most likely blind spots would have been below or behind you. Since
you were crossing LAX it seems to me unlikely the other airplane would
have been changing alititude.

This of course is all being viewed through my hindoscope -- I have 20
20 vision looking back!



On May 18, 6:27 pm, Larry Dighera > wrote:
> On Sun, 18 May 2008 14:30:55 -0400, Bob Noel
> > wrote in
> >:
>
> >That's a great way to use up a significant chunk of the error budget.
>
> That was my first thought too.
>
> However, it also brought to mind a somewhat tense situation I
> experienced while VFR transiting over KLAX via the Special Flight
> Rules Area:http://skyvector.com/#35-24-3-2785-2374
>
> The ledged for the LAXSFRA is on the VFR Terminal chart (accessible by
> clicking the Charts icon at the top of the page at that link above),
> and basically indicates that SE bound flights cross over the KLAX
> runways at 3,500' and NW bound flights at 4,500' squawking 1201 and
> communicating air-to-air on 128.55 MHz with periodic self announced
> position reports. ATC is not involved.
>
> I was flying a low-wing, and announced my position as over the
> southern boundary of the field, and immediately subsequent a Cessna
> reported being at the same position and altitude. I wanted to take
> evasive action, but without the Cessna in sight, there was no good way
> of knowing exactly what that might be. I announced again, and so did
> the Cessna, but we did not sight each other. The atmosphere got more
> tense as the moments ticked by, and I kept expecting the sounds of
> impact at any second. I considered maneuvering again, but finally
> decided, that currently I was okay, and doing nothing would likely not
> change that.
>
> I suppose I could have assumed that the Cessna was below me, and
> climbed a 100', but I didn't.

[More_Flaps]

On May 19, 10:27*am, Larry Dighera > wrote:
> On Sun, 18 May 2008 14:30:55 -0400, Bob Noel
> > wrote in
> >:
>
> >That's a great way to use up a significant chunk of the error budget.
>
> That was my first thought too.
>
> However, it also brought to mind a somewhat tense situation I
> experienced while VFR transiting over KLAX via the Special Flight
> Rules Area:http://skyvector.com/#35-24-3-2785-2374
>
> The ledged for the LAXSFRA is on the VFR Terminal chart (accessible by
> clicking the Charts icon at the top of the page at that link above),
> and basically indicates that SE bound flights cross over the KLAX
> runways at 3,500' and NW bound flights at 4,500' squawking 1201 and
> communicating air-to-air on 128.55 MHz with periodic self announced
> position reports. *ATC is not involved.
>
> I was flying a low-wing, and announced my position as over the
> southern boundary of the field, and immediately subsequent a Cessna
> reported being at the same position and altitude. *I wanted to take
> evasive action, but without the Cessna in sight, there was no good way
> of knowing exactly what that might be. *I announced again, and so did
> the Cessna, but we did not sight each other. *The atmosphere got more
> tense as the moments ticked by, and I kept expecting the sounds of
> impact at any second. *I considered maneuvering again, but finally
> decided, that currently I was okay, and doing nothing would likely not
> change that. *
>
> I suppose I could have assumed that the Cessna was below me, and
> climbed a 100', but I didn't.

Sounds like a dicey situation. I think that if you were in radio
contact the correct response would be tell the other aircraft what
your intentions are and if in the pattern that would be to hold height
and increase speed ...

You are obviously not going to run into the back of him and raising
speed should let him see you as you draw ahead.

Cheers

[Larry Dighera]

On Mon, 19 May 2008 03:42:31 -0700 (PDT), Tina >
wrote in
>:

>Do you think in a conventional high wing Cessna vs a conventional low
>wing airplane, (thinking horses here, not zebras here) since low wings
>tend to cruise a bit faster, it would have been prudent to increase
>airspeed to the maximum available and accelerate away from the threat?
>

Perhaps. However, I'm not sure there was a significant speed
differential available.

>The most likely blind spots would have been below or behind you.

It's also difficult to see directly above in a PA28 without banking.

>Since you were crossing LAX it seems to me unlikely the other airplane would
>have been changing alititude.

That's what I was hoping, but I've seen a lot of strange things occur
in the LA basin over the years.

[[email protected]]

On May 18, 10:29 pm, Benjamin Dover > wrote:
> Mxsmanic > wrote :
>
>
>
> > Benjamin Dover contributed to global warming with this opinion:
>snippage<
>
> You don't know **** from shinola.

....and another tidbit of wisdom from a pilgrim on the low road taken
all too frequently by the folks on this group.

Did you not learn from yo' momma? IF YOU DON'T HAVE ANYTHING NICE TO
SAY KEEP YOUR PIEHOLE SHUT.

[Bertie the Bunyip[_24_]]

wrote in
:

> On May 18, 10:29 pm, Benjamin Dover > wrote:
>> Mxsmanic > wrote
>> :
>>
>>
>>
>> > Benjamin Dover contributed to global warming with this opinion:
>>snippage<
>>
>> You don't know **** from shinola.
>
> ...and another tidbit of wisdom from a pilgrim on the low road taken
> all too frequently by the folks on this group.
>
> Did you not learn from yo' momma? IF YOU DON'T HAVE ANYTHING NICE TO
> SAY KEEP YOUR PIEHOLE SHUT.
>

That wasn't my momma, that was thumper's momma.. ...

Bertie

[Buster Hymen]

wrote in
:

> On May 18, 10:29 pm, Benjamin Dover > wrote:
>> Mxsmanic > wrote
>> :
>>
>>
>>
>> > Benjamin Dover contributed to global warming with this opinion:
>>snippage<
>>
>> You don't know **** from shinola.
>
> ...and another tidbit of wisdom from a pilgrim on the low road taken
> all too frequently by the folks on this group.
>
> Did you not learn from yo' momma? IF YOU DON'T HAVE ANYTHING NICE TO
> SAY KEEP YOUR PIEHOLE SHUT.

Hmmm. So you think you know **** from shinola?

[Al G[_1_]]

"John Smith" > wrote in message
...
> In article
> >,
> Tina > wrote:
>
>> We have agreed on VFR cross country flights (something that we very
>> rarely do) we will hold that kind of offset to the altitude rule as a
>> matter of routine: you might consider doing that too.
>
> The big sky theory holds true.
> How accurate is your altimeter?
> How accurate is everyone else's altimeter?

Damn close. I've used this method VFR, 7600, 9600, etc. for years, and I
have missed 2 aircraft by about 100'. I never saw either of them before they
passed. 1 was a C210 @ 12,500, I was in a C-340 @ 12,600. I first spotted
him passing underneath me, and he never even bobbled his wings. The second
was a C182, I was in a C206, again right to left, again below me. He had red
gas caps, and the left one was leaking a bit.(light blue stripe directly
aft).

I don't track the centerline of an airway(.5 mile offset), nor pass
directly over a VOR(lead the turn).

I don't even like the term "Terminal Area", and I don't call on "Final
Approach". Hell, I don't even hit an intersection.

Al G CFIAMI

[[email protected]]

On May 19, 1:58 pm, Buster Hymen > wrote:
> wrote :
>
>
>
> > On May 18, 10:29 pm, Benjamin Dover > wrote:
> >> Mxsmanic > wrote
> >> :
>
> >> > Benjamin Dover contributed to global warming with this opinion:
> >>snippage<
>
> >> You don't know **** from shinola.
>
> > ...and another tidbit of wisdom from a pilgrim on the low road taken
> > all too frequently by the folks on this group.
>
> > Did you not learn from yo' momma? IF YOU DON'T HAVE ANYTHING NICE TO
> > SAY KEEP YOUR PIEHOLE SHUT.
>
> Hmmm. So you think you know **** from shinola?

I think you learned your debate technique from MX.

[Benjamin Dover]

wrote in
:

> On May 19, 1:58 pm, Buster Hymen > wrote:
>> wrote
>>
>> :
>>
>>
>>
>> > On May 18, 10:29 pm, Benjamin Dover > wrote:
>> >> Mxsmanic > wrote
>> >> :
>>
>> >> > Benjamin Dover contributed to global warming with this opinion:
>> >>snippage<
>>
>> >> You don't know **** from shinola.
>>
>> > ...and another tidbit of wisdom from a pilgrim on the low road
>> > taken all too frequently by the folks on this group.
>>
>> > Did you not learn from yo' momma? IF YOU DON'T HAVE ANYTHING NICE
>> > TO SAY KEEP YOUR PIEHOLE SHUT.
>>
>> Hmmm. So you think you know **** from shinola?
>
> I think you learned your debate technique from MX.
>

Fjukktard!