IMC and Autopilot

ipengineer

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ipengineer
Hello everyone. I start flight training this week and have done a lot of reading on crashes that occurred during VFR flight into IMC. To me in my limited knowledge it looks like most of the situations could have been avoided and resulted from poor decision making.

So to my question.. From what I have read it doesn't take but a few minutes for spatial disorientation to set in. When a VFR pilot finds himself in IMC conditions above his experience level, why isn't engaging the autopilot so to maintain level flight the first course of action? Is there some limitation with the autopilot in these conditions?
 
There are many different autopilots; capabilities vary significantly. Some have a tendency to roll significantly when initiated if out of roll trim. In the experimental world, the newer ones seem to be very capable, stable and many have a 180 degree turnback while holding altitude function for just the scenario you inquire about.
 
It seems though that a lot of pilots just don't engage the A/P. A lot of VFR into IMC is insidious, like JFK Jr.'s case, so pilots don't realize they need to be flying on the instruments, or letting a machine that knows how do the work.

Actually, flying on the instruments is not particularly hard. Knowing that you have to is not always easy. Instrument-rated pilots can fall victim to spatial disorientation because they don't realize they're in instrument conditions.
 
Most trainers and first purchased aircraft don't have auto pilots. By the way welcome to the forum.
 
Thanks everyone for the input. I didn't think to factor in the operating requirements for the AP.

Looking forward to starting training tomorrow and joining "the club!". Have arranged to fly three times a week and try to knock it out relatively quickly.
 
From what I have read it doesn't take but a few minutes for spatial disorientation to set in. When a VFR pilot finds himself in IMC conditions above his experience level, why isn't engaging the autopilot so to maintain level flight the first course of action?
Usually, it's because the pilot gets into such an adverse attitude/altitude/speed condition that the autopilot won't help before s/he tries it. Other causes are not realizing that s/he's in over his/her head, or not knowing how to use the autopilot properly.
Is there some limitation with the autopilot in these conditions?
Only the physical limitations of the unit itself described in its operating manual, such as speed or configuration or attitude. For example, if it has a max engagement pitch of -10 degrees and a max engagement speed of 150 knots, and you're 30 degrees nose down at 200 when you engage it, engaging the autopilot at that point might just end the day right there if it pulls the wings off. But there's no limitation in the sense of such use by such a pilot being disallowed in the regulations -- once you get in that hole, you can use any tool you have to get yourself out as long as you use it properly so that use doesn't make matters worse.
 
I seem to recall the "inadvertent IMC" procedure on a few airplanes i've seen over the years with a line item for "autopilot - engaged"

but that could just be fuzzy memory.
 
Hello everyone. I start flight training this week and have done a lot of reading on crashes that occurred during VFR flight into IMC. To me in my limited knowledge it looks like most of the situations could have been avoided and resulted from poor decision making.

So to my question.. From what I have read it doesn't take but a few minutes for spatial disorientation to set in. When a VFR pilot finds himself in IMC conditions above his experience level, why isn't engaging the autopilot so to maintain level flight the first course of action? Is there some limitation with the autopilot in these conditions?

Not all airplanes have autopilots. How many C172s have you seen with one.
A lot of older 4seat GA aircraft may have non-functional autopilots.
 
Hello everyone. I start flight training this week and have done a lot of reading on crashes that occurred during VFR flight into IMC. To me in my limited knowledge it looks like most of the situations could have been avoided and resulted from poor decision making.

So to my question.. From what I have read it doesn't take but a few minutes for spatial disorientation to set in. When a VFR pilot finds himself in IMC conditions above his experience level, why isn't engaging the autopilot so to maintain level flight the first course of action? Is there some limitation with the autopilot in these conditions?

Not all planes have an autopilot, and many planes, especially rentals, that have an autopilot, they are inoperative or unreliable. If you happen to have a good one, it would be your best option.
 
Thanks everyone for the input. I didn't think to factor in the operating requirements for the AP.

Looking forward to starting training tomorrow and joining "the club!". Have arranged to fly three times a week and try to knock it out relatively quickly.

You will (or should) be ignoring the presence or absence of an autopilot until you've earned your certificate, anyway. Likely, through the instrument rating.

Where in Dallas are you training? I heartily endorse the 3x/week schedule - you'll "git 'er done" more quickly, and have a lot of fun. Save money, too!
 
You will (or should) be ignoring the presence or absence of an autopilot until you've earned your certificate, anyway. Likely, through the instrument rating.

Where in Dallas are you training? I heartily endorse the 3x/week schedule - you'll "git 'er done" more quickly, and have a lot of fun. Save money, too!

I've got to disagree with your idea of ignoring the AP until after PPSEL. It's part of the plane and you need to learn to operate it just like the VOR and GPS. Don't use it for normal ops during training but learn how to use it so in a emergency you know what buttons to press.
 
I've got to disagree with your idea of ignoring the AP until after PPSEL. It's part of the plane and you need to learn to operate it just like the VOR and GPS. Don't use it for normal ops during training but learn how to use it so in a emergency you know what buttons to press.

I agree with that, now that you mention it; you should know how to use each and every thing in the aircraft; I do not believe in using the A/P as a matter of routine while training, however.

Good catch!
 
As pointed out many of the training airplanes don't have autopilots.
The other issue is that many CFIs don't train pilots how to use the autopilots- in many cases the CFIs don't even know how to use them. This has not only been the case with many private pilots I have flown with, but also some instrument pilots.
My philosophy is that even pre-solo student pilots need to know a little about the autopilot if it is installed. What it feels like if it is engaged, how to turn it off or disable it with the circuit breaker if it gets engaged. I will even surreptitiously engage the autopilot during a flight prior to solo to see how the student handles the situation. Later in training I introduce more functions and even have them fly some of their hood time with the autopilot.
But as also pointed out inadvertent IMC is normally not the same as it is in the airplane. It is normally more insidious. This can be simulated a little better in the simulator and when I taught in Redbirds I would give my student pilots a scenario where good VFR slowly deteriorated to IMC, a situation that was not uncommon when I lived in Rochester, NY. I had one student pilot out soloing on a day that was suppose to be CAVU when it went IMC within about 15 minutes due to un-forecast lake effect snow.
Here is an example of someone who did not understand their autopilot:
http://www.ntsb.gov/aviationquery/brief.aspx?ev_id=20110311X65739&key=1
 
I had to explain all this when JonJon crashed (shortly thereafter I flew the Navion up to my Massachusetts-based family reunion so I got mercilessly grilled about the whole thing) to my extended family. To me, it's not that non-rated pilots can't fly on instruments. In fact, given JFKjr's instruction, he probably could. The problem that gets them in trouble is that they don't realize WHEN then need to be flying on instruments. There's too much tendency to look out into the murk or darkness and not have a proper visual cue and lose control. If someone smacks them on the side of the head (or their training kicks in) and says LOOK AT THE PANEL DUMMY they can probably navigate out of many situations.

I agree if a plane has an AP you need to know how to operate it (at least how to make sure it is operating and deactivating properly). There's always going to be (and sometimes with good reason) where instructors tell you not to use the AP or the GPS or the RNAV or (if you go back far enough) the VOR when you are trying to not defeat the alleged law of primacy when learning basic airmanship or pilotage, but that doesn't mean you shouldn't be trained on it.
 
If you have it use it.
How about "If you have it learn how to use it"? I've seen lots of VFR pilots who have no idea how to use their autopilot (starting with the preflight tests to make sure it's working properly). Trying to teach yourself how to use that device once in that IMC situation might be counterproductive, especially if it isn't working properly.
 
You will (or should) be ignoring the presence or absence of an autopilot until you've earned your certificate, anyway.
I agree with JT -- if there's an autopilot in your plane, you should be learning how to use it even when you're training for PP. As noted, it might save your life some day, and it will sure make things easier in your routine VFR flying.
 
Where in Dallas are you training?

I joined the TFC out at McKinney. I live 4 minutes down the street from the airport so its a quick jog..

I heartily endorse the 3x/week schedule - you'll "git 'er done" more quickly, and have a lot of fun. Save money, too!

That was a lot of the reason for doing so. Wanted to not spend a bunch of money re-hashing the same thing. Also, things are fixing to get really busy at work so good to knock it out now.
 
How about "If you have it learn how to use it"? I've seen lots of VFR pilots who have no idea how to use their autopilot (starting with the preflight tests to make sure it's working properly). Trying to teach yourself how to use that device once in that IMC situation might be counterproductive, especially if it isn't working properly.

Oh yes.

Try to imagine the following situation (not you, Ron -- you know it).

Renter flies an older aircraft with an STEC-50. That's a two-axis autopilot with alt hold, and it's fairly common. Completely ignored until the emergency. The pilot pushes the on/off button. What happens?

Answer: NOTHING. An STEC-50 will not engage unless it has been run through its self tests. That is, you flip the control switch to TEST and let it run through its cycle, then turn it ON (it's a toggle switch separate from the on/off button). Normally, this is done during preflight.

Alt hold has its own set of risks even if it does work. An autopilot controls attitude only, and if you tell it to maintain altitude where it can't (say, due to a downdraft), it will fly you right into a stall. I've never seen a GA auto throttle, though I suppose they exist, but even that isn't enough under all circumstances.
 
Alt hold has its own set of risks even if it does work. An autopilot controls attitude only, and if you tell it to maintain altitude where it can't (say, due to a downdraft), it will fly you right into a stall. I've never seen a GA auto throttle, though I suppose they exist, but even that isn't enough under all circumstances.
Another concern is that most GA autopilots don't have envelope protection and if you engaged altitude hold to attempt recovery from a steep spiral the result could easily be a severe airframe overstress. Might even induce G-LOC.
 
I agree with JT -- if there's an autopilot in your plane, you should be learning how to use it even when you're training for PP. As noted, it might save your life some day, and it will sure make things easier in your routine VFR flying.

If an AP is in the plane on the check ride, is it fair game for the DPE to be able to ask the pilot to demonstrate knowledge on basic use of the AP?
 
If an AP is in the plane on the check ride, is it fair game for the DPE to be able to ask the pilot to demonstrate knowledge on basic use of the AP?
I think we all know that an operable autopilot is fair game on an instrument rating ride, including a requirement to fly one approach with it, so I'm guessing you're asking about a PP-ASEL ride, and the answer there, too, is "yes". It's not covered as a specific Task, but it is covered by the Automation Management item under Single-pilot Resource Management in the PP-Airplane PTS, and the examiner is required ("shall") evaluate SRM as part of this practical test. The PTS give the following guidance to the examiner on how to do that if there is an autopilot or flight management system aboard:

​
Automation Management

References: FAA-H-8083-15, FAA-H-8083-6.​
Objective:​
To determine that the applicant can effectively use the

automation features of the aircraft, including autopilot​
and flight management systems, in such a way to​
manage workload and can remain aware of the​
current and anticipated modes and status of the​
automation. The applicant should:
1. Explain how to recognize the current mode of operation of​
the autopilot/FMS.​
2. Explain how to recognize anticipated and unanticipated​
mode or status changes of the autopilot/FMS.​
3. State at any time during the flight the current mode or​
status and what the next anticipated mode or status will be.​
4. Use the autopilot/FMS to reduce workload as appropriate​
for the phase of flight, during emergency or abnormal​
operations.​
5. Recognize unanticipated mode changes in a timely manner​
and promptly return the automation to the correct mode.
See pages 11-12 of that PTS.
 
The other issue is that many CFIs don't train pilots how to use the autopilots- in many cases the CFIs don't even know how to use them.

Ain't that the truth. I was in a flying club with a plane with an S-Tec 55x with all the options, AH, VS, altitude pre-select, etc. I hired the club chief instructor for a flight to show me the autopilot. We get to the practice area and the guy pulls out the autopilot POH and starts reading at page one. Holy cow, I was paying the guy in the right seat $30/hr to read me the book? That was the 1st and last autopilot "training" flight.

I got with Brent (a club member who ended up being my partner in the Mooney), we downloaded the book, studied, then rented the plane a few times alternating who was flying and who was learning the AP. Between the two of us we quickly learned all the good features of that AP.

We did the same to thoroughly learn the 430, and we did it again to thoroughly learn the KFC-200 in the Mooney.
 
. Holy cow, I was paying the guy in the right seat $30/hr to read me the book? That was the 1st and last autopilot "training" flight.
Holy cow is right. When PIC sent an instructor out to teach me, they got one familiar with the GNS480/MX20 so that wasn't an issue. He borrowed the 55x pilots guide and read it on his own time the first evening. Picked it up pretty quick (though mostly for his own use, as I had been flying behind that AP VFR for a few years before I started the instrument rating).

Don't have altitude preselect on mine. Don't know why I didn't opt for that with all the other stuff (mostly I was getting low on panel space to stick another annunciator I guess). I've never figured out why with all that space in the 55x control head that they don't have room for the altitude info there.
 
Ain't that the truth. I was in a flying club with a plane with an S-Tec 55x with all the options, AH, VS, altitude pre-select, etc. I hired the club chief instructor for a flight to show me the autopilot. We get to the practice area and the guy pulls out the autopilot POH and starts reading at page one. Holy cow, I was paying the guy in the right seat $30/hr to read me the book? That was the 1st and last autopilot "training" flight.

I got with Brent (a club member who ended up being my partner in the Mooney), we downloaded the book, studied, then rented the plane a few times alternating who was flying and who was learning the AP. Between the two of us we quickly learned all the good features of that AP.

We did the same to thoroughly learn the 430, and we did it again to thoroughly learn the KFC-200 in the Mooney.

For the AP, you kinda have to do that (though there are some flight simulators that model certain autopilots, like the KAP-140 used in some 172SPs). But there is a nice Garmin 400/500 series simulator for learning that. And it's free.
 
My philosophy is that even pre-solo student pilots need to know a little about the autopilot if it is installed.

Mine is a little bit of an extreme example, but I think it illustrates your point: My autopilot is an old (mostly) functional Nav-o-matic 200. It has a backcourse button. It's function is to swap the course deviation indicator's (CDI) response when tuned to an ILS so as to avoid reverse sensing. This button causes this effect REGARDLESS of whether the autopilot is on or off. If you don't know this function, it could really cause a problem for you, even if you never turned the autopilot on or you purposefully turned it off.
 
But there is a nice Garmin 400/500 series simulator for learning that. And it's free.
I think it would be more accurate to say "there is a nice Garmin 400/500 series simulator for use as a teaching aid." I've had trainees who thought they knew how to use those units effectively based on playing with the free sim, and they were all wrong. It's nothing more than a training aid, not a self-contained teaching system such as the computer based training courses like this one.
 
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