Q's and thoughts about Autopilot

eagledriver101

New Member
This may seem like a dumb question/rant/personal thoughts…, but I love autopilot... I almost feel I have gotten lazy... On a VFR flight I’ll take off get to my alt, tune the VOR, and set auto pilot the whole way, and won’t turn it off till I am downwind... I can fly the plane… however, I feel I can be more efficient in the cockpit when I use it, sometimes it gets really busy especially thru Class B, tune this…squawk this, climb to, descend to, turn to blah blah… Yes, its good to know how to be busy, and maintain situational awareness while demonstrating that you can handle the pressure, but I read quote somewhere, I think it was someone’s signature.. it said something to the effect of “A good pilot knows how to ……. So they don’t have to use there good piloting skills” I think about this, is it wrong to use the technology and resources to ease the distraction and workload a pilot could face?

One of my old CFi’s would never let me use GPS or VOR’s even after I have demonstrated the ability to navigate from maps, roads, and ground references. I fly a C172 with a class cockpit, the germen 1000’s are freaking awesome, it just seems so easy now.

Professionals, what are your thoughts on autopilot and the navigation equipment? Of course at FL250 you cant really follow I-15… but in general aviation is it wrong for me use this equipment all of the time, and how is it used in a commercial flight? Does autopilot fly your approach if you’re on an ILS/DME/VOR/VISUAL ETC... Can someone give me a lifecycle example of how autopilot is used from departure to arrival in your flight?

Thanks you and sorry if I bugged anyone…
 
Ensure you feel comfortable using all levels of automation and maintaining your own level of proficiency. If you're confidence level without the autopilot has decreased somewhat...handfly. If you haven't used the autopilot in a while...hook it up. I'm not sure what your experience level is...but I would tend to handfly as much as possible, especially in singles. It will teach you to multi-task and divide your attention between flying and doing other flight tasks.

I tend to handfly to 18,000 on departure. This allows me to feel out the controls and make trim adjustments that the autopilot might mask.

Having said that, in a crew environment, you want to be careful not to overload the "non-flying" pilot. This is my #1 consideration when determining whether to handfly or not. The airline that employs me will not let the "flying pilot" do anything else but fly the airplane while hand flying...no tuning radios, no flipping switches...nothing. So all of the workload gets shifted to the NFP. In a busy environment...that's not desirable.

So, on arrivals, it depends. Into a busy airport, I might only handfly the last 1000' so I can help out the NFP. Into a small airport, I might handfly the last 10,000. That's a real treat...doesn't happen to often.

Also, some of the newer RNP RNAV approach procedures require the autopilot to fly the approach. Basically, the approaches are computer generated...and there is no "raw data" to rely on...plus the flight director does not interface well with the computer generated courses. Therefore, the autopilot is required and is the only reliable source for course tracking. The RNP approaches are great...not having the option to handfly is not so great.
 
:yeahthat:

I'd like to emphasize 767's point about learning to multi-task by hand flying. Most autopilots work so well that pilots don't monitor them as closely as they should. Hand flying will get you into the habit of continuously monitoring the flight instruments, and this will carry over to when you are letting the autopilot handle the duties.

I have seen where a pilot will make a mistake in setting up the autopilot or FMS (we all do that), but will not catch the mistake because they subconsiously trust the automation to do its thing. If they had an ingrained habit of cross checking and verifying it is likely that they would catch the problem earlier. Hand flying builds the habit of automatically scanning and cross checking, and I find that I get an uncomfortable feeling in the back of my mind if I haven't checked the instruments for a little while. That kind of ingrained response is developed by use and repetition.

767's comments about using the autopilot to lessen the workload during busy times is also spot-on.
 
plus the flight director does not interface well with the computer generated courses. Therefore, the autopilot is required and is the only reliable source for course tracking.

I'm curious about this, in my experience the autopilot is driven by the flight director, so handflying by reference to the flight director would be the same as the autopilot being on. At least, that's the way all of our aircraft operate. Did you mean something a little more complex that you were trying to explain in layman's terms?
 
I'm curious about this, in my experience the autopilot is driven by the flight director, so handflying by reference to the flight director would be the same as the autopilot being on. At least, that's the way all of our aircraft operate. Did you mean something a little more complex that you were trying to explain in layman's terms?


This would probrably explain what is going on behind the screens...

http://www.youtube.com/watch?v=TuhYd9L_d7w

I had to find a place to post this...

But I agree with B767driver. Many of the CA's I fly with in the RJ use autopilot at 600', some at 10K', some will fly it up to FL180 for the first leg, then 600' the rest of the day. I personally always handfly to at least 10K' (unless there is an abnormality), most of the time to FL180. I like to also fly at least 1 leg of each day without the flight director- no automation. I have seen very few CA's not use the FD but it makes it fun and keeps a scan going. The comment that I feel was the most important in B767driver's reply was in discussion of WHERE to handfly. For me to fly with no automation (handfly) in a very busy class B airport is not appropriate in my opinion. Coming out of somewhere like Tulsa or huntsville is where I will typically do it b/c its not too busy on the NFP, also in class B areas many times you are "maintaining visual seperation" and that is not a time to practice the handflying. As far as in the decent- If I am cleared for the visual the A/P and FD are removed, cleared for the approach in VMC-A/P disc, Instr appr in IMC- stays on til after the before landing check is complete (FAF range). My last 3 day was 14 legs, 22 hours of flying- in my 7 approaches I think I was no automation for 3, FD on for 3, and kept it coupled til 1000' on 1. The departure totals where about the same- I did click the autopilot on at 600' on one due to a master caution that needed a QRH (it was a minor thing). Hope that gives you an idea of the RJ world...
 
I'm curious about this, in my experience the autopilot is driven by the flight director, so handflying by reference to the flight director would be the same as the autopilot being on. At least, that's the way all of our aircraft operate. Did you mean something a little more complex that you were trying to explain in layman's terms?

I don't know enough about the systems to get too technical, but I do know in the airplane's I've flown over the last ten years, the flight director and autopilot are different and separate components independant of each other. They are commonly powered by a common flight control computer...but the FMS & FCC will send commands to the AP & FD independantly.

You could fly with the AP on and FD off, or FD on and & AP off. One thing is definitely noticable though...and I'm not sure why that is...and its that the FD does not track FMS generated courses as precisely as the AP does. This does not hold true for raw data courses (ILS/GS/VOR)...but is noticeable when flying RNAV approaches, departures and arrivals.
 
Interesting...

In the CRJ the FMS and navaid routing is filtered through the FCC and send to the FD (actually, two FCCs send data to the onside FD although they are slaved to one side except during GAGA/TOTO/ILS). The autopilot, when on, simply follows the FD cues. In other words, turning off the FD will turn off the AP, but you can kill the AP and still hand fly with an FD.
 
Interesting...

In the CRJ the FMS and navaid routing is filtered through the FCC and send to the FD (actually, two FCCs send data to the onside FD although they are slaved to one side except during GAGA/TOTO/ILS). The autopilot, when on, simply follows the FD cues. In other words, turning off the FD will turn off the AP, but you can kill the AP and still hand fly with an FD.

Same in our airplanes, which is why I was confused. B767Driver, maybe that's just a Boeing peculiarity? Have you flown other manufacturers equipment in the last 10 years?
 
Same in our airplanes, which is why I was confused. B767Driver, maybe that's just a Boeing peculiarity? Have you flown other manufacturers equipment in the last 10 years?

Just Boeing and McDonnel Douglas. The MD-88 was the same way. The flight director was late tracking FMS generated courses. If you were hand-flying...you hand to fly through the flight director and lead turns to course changes. The autopilot was right on, however.

You could watch the AP start the turn...and the FD command bars would not indicate a turn for a while.
 
I've flown 2 different aircraft with FD and autopilot systems. One was the T-1, which is a military version of the Beech 400. In that aircraft, you programmed the flight director, and all the autopilot did was fly off of whatever the flight director said.

In the KC-135 (which is basically a B-707 airframe) it was the exact opposite. The autopilot and the flight director were completely separate systems. You could have the flight director coupled to a heading bug and altitude hold mode, while the autopilot was trying to fly off of a VOR or FMS course and hold an indicated Mach number. So they could be set up to do two completely different things. In addition, the pilot's flight director could be set up to show different information than the co-pilot's.

I guess the advantage of that system is that with the autopilot, pilot's FD and co-pilot's FD all separate, you have to have ALL 3 set improperly the same way, or one of them will show some screwy information. Hopefully that will catch your eye if one of them screws up. Keeping all three set togther was a pain, though.

The system on the Beech was easier to operate. But at the same time, if you screwed it up in the flight director, the autopilot is going to fly it the same way the flight director says. So you don't get that warning.
 
On RNAV departures, use of the AP is RECOMMENDED on the RJ, but it's not required. The FD IS required, though. Nothing in our manuals says we HAVE to use the AP, just that it's recommended. If you're departing off runway 1 in DCA and you hit AP at 600 AGL, you're gonna get in trouble when it busts the restricted area. It won't make the turn fast enough.

Ken, I think we've flown with a few of the same CAs....

I'll normally hand fly to 10K-18K, most of the time somewhere in the middle. If it's a visual approach, odds are the FD is coming off since it's gonna be telling me to go somewhere else anyway. If it's a traffic pattern, I'll hand fly the whole thing. Coming into RIC today, the cleared us for a visual to 20 on about a 5 mile right base. It was EASIER to hand fly than twist knobs and set headings and altitudes. Even though the CRJ has all this fancy equipment, sometimes it's just easier to remember one thing: it's still an airplane.

A VERY valid point was made about handflying and trimming. A lot of times, the AP won't trim the plane out correctly, and when you turn it off, the plane is not where you want it to be. If you get the trims set by handflying, THEN turn it on, most of the time you're set up fine when you click it back off for the approach and landing. Of course, you're still gonna have to hit the stab trim, but your aileron and rudder trims are set.

I had a deferred AP going from MEM-TYS yesterday, and I wanted to hurt whoever designed the beverage cart. Everytime our FA moved back a few aisles, I had to re-trim.
 
A VERY valid point was made about handflying and trimming. A lot of times, the AP won't trim the plane out correctly, and when you turn it off, the plane is not where you want it to be. If you get the trims set by handflying, THEN turn it on, most of the time you're set up fine when you click it back off for the approach and landing. Of course, you're still gonna have to hit the stab trim, but your aileron and rudder trims are set.

Master Jedi says disconnect the autopilot with one click of nose up trim and the yoke doesn't dance all over the place. Happy you will be.
 
Master Jedi says disconnect the autopilot with one click of nose up trim and the yoke doesn't dance all over the place. Happy you will be.


Humphfff.... Off course..... Humphfff..... Off Altitude..... A Jedi craves not these things.
 
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