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Roy Smith
June 1st 04, 05:28 PM
The ODP out of MMK for runway 36 reads, "climbing left turn to 1800 via
325° bearing from MMK NDB before proceeding on course".

It seems to me that the easiest way to fly that with a GPS would be to
create a user waypoint which is a 325 bearing, 20 (or whatever) mile
offset from MMK NDB and insert that into your flight plan before the
first real waypoint in your clearance. Take off, track to the user
waypoint until reaching 1800, then do "direct" to the next waypoint.
Can anybody think of a good reason not to do it that way?

Brad Z
June 1st 04, 05:40 PM
As long as you hit the goto button for the homemade waypoint reasonably near
the ndb, it sounds like it should work. The alternative is to treat the ndb
like a vor and fly the 325 "radial" after takeoff.

"Roy Smith" > wrote in message
...
> The ODP out of MMK for runway 36 reads, "climbing left turn to 1800 via
> 325° bearing from MMK NDB before proceeding on course".
>
> It seems to me that the easiest way to fly that with a GPS would be to
> create a user waypoint which is a 325 bearing, 20 (or whatever) mile
> offset from MMK NDB and insert that into your flight plan before the
> first real waypoint in your clearance. Take off, track to the user
> waypoint until reaching 1800, then do "direct" to the next waypoint.
> Can anybody think of a good reason not to do it that way?

Greg Esres
June 1st 04, 06:08 PM
<<Can anybody think of a good reason not to do it that way?>>

Sounds unnecessarily complicated. Brad Z's suggestion is far easier,
IMO.

June 1st 04, 07:39 PM
Roy Smith wrote:

> The ODP out of MMK for runway 36 reads, "climbing left turn to 1800 via
> 325° bearing from MMK NDB before proceeding on course".
>
> It seems to me that the easiest way to fly that with a GPS would be to
> create a user waypoint which is a 325 bearing, 20 (or whatever) mile
> offset from MMK NDB and insert that into your flight plan before the
> first real waypoint in your clearance. Take off, track to the user
> waypoint until reaching 1800, then do "direct" to the next waypoint.
> Can anybody think of a good reason not to do it that way?

The procedure is designed with the expectation you will use the OBS mode
until leaving 1800, then return to the legs mode and go direct.

Can't be much simplier than that.

Doug
June 2nd 04, 06:59 AM
Probably the least understood feature of an IFR GPS is OBS mode.

wrote in message >...
> Roy Smith wrote:
>
> > The ODP out of MMK for runway 36 reads, "climbing left turn to 1800 via
> > 325° bearing from MMK NDB before proceeding on course".
> >
> > It seems to me that the easiest way to fly that with a GPS would be to
> > create a user waypoint which is a 325 bearing, 20 (or whatever) mile
> > offset from MMK NDB and insert that into your flight plan before the
> > first real waypoint in your clearance. Take off, track to the user
> > waypoint until reaching 1800, then do "direct" to the next waypoint.
> > Can anybody think of a good reason not to do it that way?
>
> The procedure is designed with the expectation you will use the OBS mode
> until leaving 1800, then return to the legs mode and go direct.
>
> Can't be much simplier than that.

John Bell
June 2nd 04, 07:25 AM
> The ODP out of MMK for runway 36 reads, "climbing left turn to 1800 via
> 325° bearing from MMK NDB before proceeding on course".
>
> It seems to me that the easiest way to fly that with a GPS would be to
> create a user waypoint which is a 325 bearing, 20 (or whatever) mile
> offset from MMK NDB and insert that into your flight plan before the
> first real waypoint in your clearance. Take off, track to the user
> waypoint until reaching 1800, then do "direct" to the next waypoint.
> Can anybody think of a good reason not to do it that way?

There are a couple ways of navigating this with the GPS, The best method
depends on what kind of GPS you are using. Here is my $.02 worth of
opinion:

If you have an IFR certified panel mounted GPS, I would execute a direct MMK
and use the OBS mode. If I read the AIM correctly, it appears that you
would have to have the CDI mode set to terminal sensitivity (normally 1 to
1.25 nm) to use the GPS for navigation without having an ADF (AIM 1-1-19f,
http://www.faa.gov/ATpubs/AIM/Chap1/aim0101.html#1-1-19). For example, on
the Garmin 400 series you would have to page 3 of the AUX menu to change the
CDI from enroute sensitivity. I would recommend displaying cross track
also. I would recommend a second opinion rather than depend on my quick
late night interpretation of the AIM.

When you are ready to go to the next waypoint in the flight plan, just
execute a direct. Depending on the GPS, it may come out of OBS mode, but
make sure that it does.


The technique that you mention should work. If you were to create a
waypoint as you say, on most GPS receivers you would want to make the first
point in the flight plan MKK and the second point the waypoint that you
create. When you activate the flight plan, the active waypoint will be the
created waypoint and MKK would anchor the first leg. The XTK value would
reference this leg. Be careful about using this technique with a VOR
because VOR's are often slightly out of alignment with magnetic north. Obvi
ously, make sure the GPS is set to reference magnetic rather than true
north.

If you are using a handheld aviation GPS with an HSI, you might consider
using the OBS and HOLD option with the 145 bearing. The needle will still
indicate the correct displacement direction even when set on the TO bearing,
but the advantage is that the line on the map will be along the 325
outbound -- better situational awareness. Obviously, the GPS would only be
for situational awareness and you would have an ADF. I tend to like data
fields and TURN, which is the difference between TRACK and BEARING, is one
of my favorites. You can use XTK (OFF COURSE on some handhelds) in
conjunction with TURN as data fields. Choose a heading to keep TURN between
L179 and R179 and make slight adjustments to XTK.

If you really want to be adventurous, just execute a direct to MKK. Moving
clockwise causes the bearing to increase and counterclockwise causes it to
decrease. Since the GPS bearing is the bearing TO, you would want to fly
outbound so that the GPS bearing was equal to 145. Once established, you
can use TRACK to help stay on course.

John Bell
www.cockpitgps.com

Stan Gosnell
June 2nd 04, 11:18 PM
Roy Smith > wrote in
:

> The ODP out of MMK for runway 36 reads, "climbing left turn
> to 1800 via 325° bearing from MMK NDB before proceeding on
> course".
>
> It seems to me that the easiest way to fly that with a GPS
> would be to create a user waypoint which is a 325 bearing,
> 20 (or whatever) mile offset from MMK NDB and insert that
> into your flight plan before the first real waypoint in
> your clearance. Take off, track to the user waypoint until
> reaching 1800, then do "direct" to the next waypoint. Can
> anybody think of a good reason not to do it that way?

The easiest way on the GPS I use is to bring up MMK, then select
325 degrees from, and then keep the needle centered. No need
for another waypoint. After reaching 1800, just go direct to
the first waypoint.

--
Regards,

Stan

Roy Smith
June 2nd 04, 11:36 PM
In article >,
Stan Gosnell <me@work> wrote:

> Roy Smith > wrote in
> :
>
> > The ODP out of MMK for runway 36 reads, "climbing left turn
> > to 1800 via 325° bearing from MMK NDB before proceeding on
> > course".
> >
> > It seems to me that the easiest way to fly that with a GPS
> > would be to create a user waypoint which is a 325 bearing,
> > 20 (or whatever) mile offset from MMK NDB and insert that
> > into your flight plan before the first real waypoint in
> > your clearance. Take off, track to the user waypoint until
> > reaching 1800, then do "direct" to the next waypoint. Can
> > anybody think of a good reason not to do it that way?
>
> The easiest way on the GPS I use is to bring up MMK, then select
> 325 degrees from, and then keep the needle centered. No need
> for another waypoint. After reaching 1800, just go direct to
> the first waypoint.

Several people have suggested this, and I've come to realize they (and
you) are right. My "make up a waypoint" idea was really driven by an
attempt to use those parts of the box I knew and avoid learning the rest
of it. Bad on me.

Stan Gosnell
June 3rd 04, 12:42 AM
Roy Smith > wrote in
:

> Several people have suggested this, and I've come to
> realize they (and you) are right. My "make up a waypoint"
> idea was really driven by an attempt to use those parts of
> the box I knew and avoid learning the rest of it. Bad on
> me.

I think it's worth the effort to learn everything about the box.
You never know when you might need some obscure feature. I use
the "make up a waypoint" method a lot, when flying OSAP
(Offshore Standard Approach Procedure) approaches offshore. We
get the wind, then make up a waypoint directly downwind of our
destination, using distance/bearing from the destination, to use
as an IAF. It works, but the GPS tends to build up lots of
cryptic waypoint identifiers that mean nothing to anyone. There
are lots of A and AA user waypoints, simply because that's the
easiest thing to do quickly. I would prefer not to do it this
way, but that's what the ops specs specify.

--
Regards,

Stan

June 4th 04, 04:01 PM
Doug wrote:

> Probably the least understood feature of an IFR GPS is OBS mode.

I don't know. The knowledge level for a lot of folks is pretty meager on
functions other than the OBS mode.

The training leaves a lot to be desired.

I took a good friend who was getting no where with his Garmin 500. We spent
two four hour sessions using the trainer at a PC, and now he is a pro.

June 4th 04, 04:04 PM
John Bell wrote:

> > The ODP out of MMK for runway 36 reads, "climbing left turn to 1800 via
> > 325° bearing from MMK NDB before proceeding on course".
> >
> > It seems to me that the easiest way to fly that with a GPS would be to
> > create a user waypoint which is a 325 bearing, 20 (or whatever) mile
> > offset from MMK NDB and insert that into your flight plan before the
> > first real waypoint in your clearance. Take off, track to the user
> > waypoint until reaching 1800, then do "direct" to the next waypoint.
> > Can anybody think of a good reason not to do it that way?
>
> There are a couple ways of navigating this with the GPS, The best method
> depends on what kind of GPS you are using. Here is my $.02 worth of
> opinion:
>
> If you have an IFR certified panel mounted GPS, I would execute a direct MMK
> and use the OBS mode. If I read the AIM correctly, it appears that you
> would have to have the CDI mode set to terminal sensitivity (normally 1 to
> 1.25 nm) to use the GPS for navigation without having an ADF (AIM 1-1-19f,
> http://www.faa.gov/ATpubs/AIM/Chap1/aim0101.html#1-1-19).

All the IFR units are 1.0 mile in terminal. 1.25 is in some VFR-only units. The
procedure requires you set the unit to terminal mode in an RNAV DP.

Those VA legs (leg to altitude) expect you to use the OBS mode or some similar
open track mode.

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