Typical KAP150 bank angle

[M252]

Hello Mooniacs,

what typical bank angles do you see on your Mooneys with a KAP150 A/P installed?

I see about 15-18° bank and it is always a standard turn, i.e. I never see steeper turns. I was told the KAP150 can do up to 25°, which I never see.

Trying to figure out if this is normal.

Thanks,

M252

 

 

[carusoam]

The bank angle of a standard rate turn is directly dependent on airspeed.  To get to a 25° bank to maintain a standard rate turn, you would really be moving quickly...

I believe training for the IR they select a standard approach airspeed and calculate a 17° bank angle to get the standard rate...

there is probably a chart of an equation to explain this somewhere...

PP thoughts, not a CFI...

Best regards,

-a-

[M252]

I am aware of the relationship between speed and bank angle but the bank angle is always the same on my machine.

Do you see different bank angles at different speeds with the A/P engaged (HDG mode)?

[carusoam]

Mine looks likes like it goes to 17° and stays there until it rolls out on the heading bug.

I watch for the bank angle to make sure it doesn't continue to roll.  Beyond that, I have not compared airspeed vs bank angle.  

I get the feeling the KAP 150 may be using the 17° bank angle as a good approximation(?).  Which is more important cruise speed or approach speed...?

The computing power and memory of the KAP150 is 90s technology.  It may have limitations like this...?

Wondering if that is a settable variable.  Would we be able to select a better angle to help a GPSS with turn anticipation.

my hand coordinated turn anticipation wouldn't improve very much if I rolled to 20° of bank.  Starting the turn manually requires too much accuracy to make a difference...

i would gamble that the 17° bank angle matches the approach speed that the airplane has for IAPs.  Probably set by the STC related to the aircraft.  Less important than the accuracy of a turn at cruise speed at altitude where the victor airway is 4nm wide.

great duscussion...

Best regards,

-a-

 

[flyboy0681]

1 hour ago, carusoam said:

 

The computing power and memory of the KAP150 is 90s technology.  

 

As far as I know, the KAP 150 started showing up on the scene during the 1981 model year. It could have been earlier.

[Bennett]

I have a Icarus SAM for GPSS steering, with a KAP 150. I've never seen it bank more than 17 degrees; mostly 15 degrees or so. With the SAM disengaged, the KAP 150 usually is 15-18 degrees. Without the autopilot engaged, I tend to bank 20-25 degrees, watching the ball carefully.

[M252]

Thanks, I agree that 15-18° is not a lot to capture the final approach on GPS approaches etc. I tend to slow down to ~120 KIAS on any IFR approach to help.

So it seems I am seeing normal KAP150 behavior.

[carusoam]

IIRC...

you need to spin the heading bug quickly upon the indication from the turn anticipation to stay close to the CL too slow to start the turn will exceed the lateral limits.

This is an old memory.  I have not been IFR current in a few years...

Best regards,

-a-

[Parker_Woodruff]

Autopilot should hold aircraft in standard rate turn.  The slower the speed, the less bank.  The faster the speed, the more bank. 

Remember from primary training how you get a fast rate of turn when flying in slow flight and only using 5-10 degrees of bank?

[floridaflyer]

My KFC150 can't bank steeper than around 17 deg I usually switch to CWS to manually bank steeper so I'm not at it all day... I would love being able to adjust it.

[flyboy0681]

I was out two weeks ago putting the KAP 150 through its paces and noticed that while cruising along at 75% power a 90 degree turn yielded a maximum of 15 degrees bank regardless of speed.

Edited August 20, 2016 by flyboy0681

[carusoam]

Dp or TP or quadruple post.... 

-a-

[Guillaume]

8 hours ago, flyboy0681 said:

I was out two weeks ago putting the KAP 150 through its paces and noticed that while cruising along at 75% power a 90 degree turn yielded a maximum of 15 degrees bank regardless of speed.

The KAP100 series autopilot is an attitude based autopilot without airspeed input.

Technically it can only provide a fixed bank angle which was set by the factory around 17~18°.

So, in a Mooney, the KAP100 series won't make a rate 1 turn unless your flying at about 120 KTAS.

 

The max bank angle can be set by an appropriate autopilot shop.

I flew a TB20 equipped with a KAP100 which made 25° degrees bank. Can be surprising during approach !

Edited August 21, 2016 by Guillaume

[LANCECASPER]

If you don't have one already, may I suggest a Pilot's Guide for the King Autopilot?

http://www.ebay.com/itm/112103606028?item=112103606028&viewitem=&vxp=mtr

[AndyFromCB]

3 hours ago, LANCECASPER said:

If you don't have one already, may I suggest a Pilot's Guide for the King Autopilot?

http://www.ebay.com/itm/112103606028?item=112103606028&viewitem=&vxp=mtr

Here is the freebie version

https://www.bendixking.com/HWL/media/Pilot-Guides/006-08377-0001_1.pdf

 

[N201MKTurbo]

The CAP150 is an attitude based autopilot. It has no idea how fast you are going. The maximum bank angle is adjustable. It should be adjusted to give you a standard rate turn at the speed you fly instrument procedures. If it doesn't have your avionics guy adjust it, or look up where the adjustment is and do it yourself.

[N201MKTurbo]

Did you happen to notice what airplane panel is on the introduction page of the pilots guide?

[carusoam]

https://flightaware.com/resources/registration/N222KR

based on the tail number in the photo.

Best regards,

-a-

[floridaflyer]

On 8/21/2016 at 4:20 AM, Guillaume said:

The KAP100 series autopilot is an attitude based autopilot without airspeed input.

Technically it can only provide a fixed bank angle which was set by the factory around 17~18°.

So, in a Mooney, the KAP100 series won't make a rate 1 turn unless your flying at about 120 KTAS.

 

The max bank angle can be set by an appropriate autopilot shop.

I flew a TB20 equipped with a KAP100 which made 25° degrees bank. Can be surprising during approach !

Can someone post the service manual for the  KFC150 (it's not the same as the pilot's guide or the installation manual)?

Thanks.

[carusoam]

ff,

Check BK's website.  They are really amazing for making their manuals available.

Best regards,

-a-

 

[floridaflyer]

carusoam, there are no service manuals to be found on the Bendix King website,