Autopilot use during approach

Ron Natalie writes:

Untrue. Autopilot installations are one of the more rigorously handled
aircraft modifications. There will certainly be LEGALLY BINDING
operating limitations that apply to the use of the autopilot.

Yes, but they aren't in the FARs. In general, as long as you do not rely on
the autopilot to do something you cannot do by hand, you're fine.

--
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Mxsmanic wrote:
Ron Natalie writes:


Untrue. Autopilot installations are one of the more rigorously handled
aircraft modifications. There will certainly be LEGALLY BINDING
operating limitations that apply to the use of the autopilot.


Yes, but they aren't in the FARs. In general, as long as you do not rely on
the autopilot to do something you cannot do by hand, you're fine.


WRONG!

If your POH supplement for the autopilot has operating limitations, it
isn't legal to use contrary to those limitations. Mine doesn't allow
use of the autopilot with the landing lights on, for example. You won't
find these anywhere in the AIM or FARs, but they are just as binding as
one of the regulations. You also potentially have more at stake by
ignoring an operation limitation than you do by breaking a FAR.

Then again, if you are only flying a simulator then I suppose the
operating limitations don't apply. After all, the worst thing that
could happen is you'd have to push the reset button.

Ray Andraka wrote:


If your POH supplement for the autopilot has operating limitations, it
isn't legal to use contrary to those limitations. Mine doesn't allow
use of the autopilot with the landing lights on, for example. You won't
find these anywhere in the AIM or FARs, but they are just as binding as
one of the regulations.

But it is one of the regulations...91.9 causes anything that's in
the flight manual limitations to have the force of regulation.

I've pointed this out to McMuffin before but he refuses to learn.

Ray Andraka writes:

If your POH supplement for the autopilot has operating limitations, it
isn't legal to use contrary to those limitations.

This does not conflict with "in general," and "they aren't in the FARs.

--
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Wow. I never would have guessed that. What is the rationale the
landing lights, current draw?

If your POH supplement for the autopilot has operating limitations, it
isn't legal to use contrary to those limitations. Mine doesn't allow use
of the autopilot with the landing lights on, for example.

Ron,

As Jim says, there's advice on that in the POH. Keep in mind that the
S-TEC 50 does not intercept/capture radials or localizers. You have to
get the plane onto the localizer (which can of course be done with the
AP in heading mode). Only after that you can engage the approach mode.
Main difference between approach and nav is the sensitivity. With the
S-TEC 50, you will still have to manage the altitude profile yourself.

I have seen vastly different accuracy on different installations in
different aircraft with the S-TEC 50. On our Tobago, it can be used
well on approaches down to 200 feet.

--
Thomas Borchert (EDDH)

On Fri, 13 Apr 2007 13:01:32 +0200, Thomas Borchert
wrote:

Ron,


I have seen vastly different accuracy on different installations in
different aircraft with the S-TEC 50. On our Tobago, it can be used
well on approaches down to 200 feet.

In my Mooney, I will occasionally allow my STEC50 to fly an approach, if
there is absolutely no turbulence and little change in the winds during
descent. Sometimes it even gets to DH/MDA still on the centerline! But
it's not unusual for it to get 1/2 to 3/4 scale off course.
Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

Ron,

But
it's not unusual for it to get 1/2 to 3/4 scale off course.


I know. A friend of mine has similar issues in a BN-2.

--
Thomas Borchert (EDDH)

On Fri, 13 Apr 2007 18:13:38 +0200, Thomas Borchert
wrote:

Ron,

But
it's not unusual for it to get 1/2 to 3/4 scale off course.


I know. A friend of mine has similar issues in a BN-2.

And here I thought all those big planes had decent autopilots!

Years ago, a few years after installation, I called STEC and they thought
that increasing the sensitivity of the autopilot might help. They gave
instructions on changing a resistor, and that helped a bit, but I still
wouldn't trust it in other than smooth weather.
Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

I have an STEC 30, which is electronically the same as the 50, I
think. I've found it to be extremely accurate, keeping the localizer
centered all the way down. You do have to intercept the localizer
within 10 degrees of the localizer heading before activating the
autopilot. I use it occasionally, on the theory of keeping all skills
current.