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Old January 7th 07, 05:30 AM posted to rec.aviation.piloting,rec.aviation.student
C J Campbell[_1_]
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Posts: 799
Default Holds on autopilot?

On Sun, 31 Dec 2006 11:43:00 -0800, Robert M. Gary wrote
(in article .com):


Mxsmanic wrote:
In real life, do most pilots equipped with autopilots use them to fly
holds (i.e., by using the HDG function of the autopilot, and possibly
altitude holds or autothrottle if available), or do they fly the plane
by hand through the holds?


Even in the very advanced G1000 aircraft the autopilot doesn't fly the
hold. However you can manually set the heading and drive it around the
hold. The GNS 480 will drive the hold and is awesome but its just a
box, not an integrated system like the G1000.
The best thing about any IFR GPS system (430,480,530,G1000) is that it
gives you the entry procedure. That's 95% of the complexity of the
hold, fingering out the entry.

When you are tested on your ability to fly holds, do you have to fly
them by hand, or can you use the autopilot as above?


Usually when you are being tested on holding you are being tested on
two things...
1) Using a correct entry procedure (or at least staying on the safe
side) and


Actually, you can use any entry procedure you want as long as you stay on the
safe side. An examiner is not going to ask for a teardrop entry, for example.
The purpose of the recommended entry procedures is to give you easily
remembered means of ensuring that you stay on the safe side.

2) Timing the hold to arrive back at the holding fix right at the EFC
time. A hold can be 4,3 or 2 minutes so you mix them up to make the
time come out right.
Just the flying around in circles part isn't anything difficult itself.


You time the hold so that the inbound leg is one minute (or 1.5 minutes). You
can be anywhere in the hold at EFC time. The important thing is that you do
not leave the hold before the EFC time without a clearance. If I am on the
inbound leg and the EFC time is approaching and I have not gotten a further
clearance, I will call ATC. No point in letting everybody fall asleep at the
switch.

Note that I'm not talking about fully automated systems that will fly
the entire hold pattern automatically, I'm talking about just using
heading and altitude controls in the autopilot to simplify the task of
turning and rolling out, turning and rolling out, over and over.


Usually you do use the autopilot, because the hold is usually when you
are briefing the approach. Pre-approach is the busiest time because you
need to study the approach.

In real life holding is about as common as being hit by lightening.
Even when you do get a hold its usually just a vectored hold, not a
formal procedures. The only time you really get to fly holds is to
remote airports without ATC when the approach procedure requires a hold
for the procedure turn.


Well, holds are a little more common than that. However, they are not as
common as they used to be. I miss them, in an odd sort of way. Some
departures also have holds in them for climbing to cruise altitude. IIRC
Missoula has one of these. Sometimes you also are given holding instructions
when you receive your departure clearance at a non-towered airport.