# Thread: Standard Rate Turn

1. ## Standard Rate Turn

I'm having trouble getting the autopilot to turn fast enough. I'm using a
Citation X.

From a previous thread, I know there's an autopilot bank angle setting in
the aircraft.cfg file, and I changed that from 20 to 25, but the bank angle

I'm getting isn't anywhere near that. I just tried changing that to 30,
hoping that will work.

Also I noticed PM offset x552A, which is be default set at 25. I'm going to

experiment with a higher value. The docs say that setting it at 1 is
"AUTO". Has anyone had similar problems and made adjustments that worked?

Thanks!

David Rabiner

2. ## Standard Rate Turn

How slow is too slow???

Having actaully flown a Citation in the real world, I can tell you that
standard rate turns are relative. If you are talking about being able to make a
complete circle (with or without) the autopilot within 2 minutes you would
need such a bank angle at those kind of speeds that you would make the
passengers very unhappy not to mention the G load you would put on the
aircraft. The fast you go the longer it will take to make the turn.

Phil

3. ## Re: Standard Rate Turn

That's a great point, Phil.

I think I remember reading somewhere that, at higher speeds, the autopilot
should command 1/2 standard rate, which is 1.5 degrees per second.

I wonder if higher speeds means cruise speed as well. What turn rate do you

figure a real Citation (or any other jet, for that matter) autopilot would
command at cruise speed. If it's 1/2 standard rate, that means a 30 degree

turn at a waypoint would take 20 seconds...

I have no idea. I've never flown anything bigger than a Cessna 172!

David

4. ## Re: Standard Rate Turn

David,

Just POF for my ATPL's and doing Turn rates etc forrmula below will work out
the radius, not sure about AP speeds etc though

For this one you must use the formula Radius = TAS (squared) divided by g
(9.81m/s/s) x Tan bank angle

You must must use SI units so convert the speed from knots to meters per
second. Kts x 0.515 is good enough.

regards Paul

5. ## Re: Standard Rate Turn

Now that was a fun little formula to play with!

D