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Gene Whitt
January 9th 05, 06:06 AM
Y'All,
I've been digging through FAA-H-8261-1 Instrument Procedures Handbook and
cannot find the answer clearly stated.

I would like to know in what respects the following types of waypoints are
differentiated by creation, useage, and otherwise.
A source text would be helpful as well.

Charted waypoint
Floating waypoint
Phantom waypoint

Gene Whitt

January 9th 05, 01:34 PM
I work with ARINC 424 RNAV specs all the time, and have never heard those
terms.

Gene Whitt wrote:

> Y'All,
> I've been digging through FAA-H-8261-1 Instrument Procedures Handbook and
> cannot find the answer clearly stated.
>
> I would like to know in what respects the following types of waypoints are
> differentiated by creation, useage, and otherwise.
> A source text would be helpful as well.
>
> Charted waypoint
> Floating waypoint
> Phantom waypoint
>
> Gene Whitt

Cheetah236
January 9th 05, 02:39 PM
Gene Whitt wrote:

> I would like to know in what respects the following types of
waypoints are
> differentiated by creation, useage, and otherwise.
> A source text would be helpful as well.
>
> Charted waypoint
> Floating waypoint
> Phantom waypoint

I think the Phantom waypoint might just be any that doesn't exist in
the database. For example, on MMV VOR/DME or GPS-B approach,
(http://www.naco.faa.gov/d-tpp/0413/05626VDGB.PDF), UBG 13.5 DME is the
last stepdown fix but is not in the GPS database. It can be legally
calculated as the DME difference between it and the MABEZ intersection
(MAP).

My NOrthstar GPS manual refers to what they call a phantom waypoint
that is created by using the lat/lon from a Loran. They acknowledge in
the manual that this could be inaccurate given any reception anomalies
in the area. (And of course would be illegal to use in any primary IFR
operations).

My _guess_ is that, in this context, a charted waypoint would be in the
database instead of home-brewed?

kage
January 9th 05, 04:36 PM
These are FMS terms. A charted waypoint is just that, one on the charts, and
it's in the box. A floating waypoint is one which the FMS computes, like TOD
(top of descent), it's position changes with groundspeed.

A phantom waypoint is one where the pilot builds a waypoint in the box. Say
your clearance is out the 270SEA radial to intercept some other radial. It
is often easier to build a waypoint at the intersection than to mess with
VHF nav. FMS likes to go point to point.

Karl

"Cheetah236" > wrote in message
oups.com...
>
> Gene Whitt wrote:
>
>> I would like to know in what respects the following types of
> waypoints are
>> differentiated by creation, useage, and otherwise.
>> A source text would be helpful as well.
>>
>> Charted waypoint
>> Floating waypoint
>> Phantom waypoint
>
> I think the Phantom waypoint might just be any that doesn't exist in
> the database. For example, on MMV VOR/DME or GPS-B approach,
> (http://www.naco.faa.gov/d-tpp/0413/05626VDGB.PDF), UBG 13.5 DME is the
> last stepdown fix but is not in the GPS database. It can be legally
> calculated as the DME difference between it and the MABEZ intersection
> (MAP).
>
> My NOrthstar GPS manual refers to what they call a phantom waypoint
> that is created by using the lat/lon from a Loran. They acknowledge in
> the manual that this could be inaccurate given any reception anomalies
> in the area. (And of course would be illegal to use in any primary IFR
> operations).
>
> My _guess_ is that, in this context, a charted waypoint would be in the
> database instead of home-brewed?
>

Gene Whitt
January 9th 05, 09:29 PM
Karl, et al,
Thank you for the information. Is is so much like the FAA to print a
text for all of aviation without clarifying the level of aircraft involved
and the equipment required.

I am in the process of making a selective revision of the material so that
the inappropriate material for Part 91 pilots is mentioned but not
emphasized.
Gene



"kage" > wrote in message
...
> These are FMS terms. A charted waypoint is just that, one on the charts,
> and it's in the box. A floating waypoint is one which the FMS computes,
> like TOD (top of descent), it's position changes with groundspeed.
>
> A phantom waypoint is one where the pilot builds a waypoint in the box.
> Say your clearance is out the 270SEA radial to intercept some other
> radial. It is often easier to build a waypoint at the intersection than to
> mess with VHF nav. FMS likes to go point to point.
>
> Karl
>
> "Cheetah236" > wrote in message
> oups.com...
>>
>> Gene Whitt wrote:
>>
>>> I would like to know in what respects the following types of
>> waypoints are
>>> differentiated by creation, useage, and otherwise.
>>> A source text would be helpful as well.
>>>
>>> Charted waypoint
>>> Floating waypoint
>>> Phantom waypoint
>>
>> I think the Phantom waypoint might just be any that doesn't exist in
>> the database. For example, on MMV VOR/DME or GPS-B approach,
>> (http://www.naco.faa.gov/d-tpp/0413/05626VDGB.PDF), UBG 13.5 DME is the
>> last stepdown fix but is not in the GPS database. It can be legally
>> calculated as the DME difference between it and the MABEZ intersection
>> (MAP).
>>
>> My NOrthstar GPS manual refers to what they call a phantom waypoint
>> that is created by using the lat/lon from a Loran. They acknowledge in
>> the manual that this could be inaccurate given any reception anomalies
>> in the area. (And of course would be illegal to use in any primary IFR
>> operations).
>>
>> My _guess_ is that, in this context, a charted waypoint would be in the
>> database instead of home-brewed?
>>
>
>

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