[Paparazzi-devel] aircraft tuning question

[John Burt]

Hey folks,

I'm in the process of tuning the flight behavior of my Multiplex Cularis 
airframe using a Tiny 2.11 AP. Until recently, I had the plane flying 
quite well, with reasonable tracking of flight lines, circles and 
waypoints. I have to say, it's a real joy to see this elegant (yet 
cheap!) aircraft flying itself around the field.

However, I had serious problems when I recently launched the plane with 
a radio-direction finder pod attached 
(http://paparazzi.enac.fr/wiki/User:John_Burt#Cularis). Long story 
short, the top-mounted payload makes the aircraft unstable at low speeds 
and I need to increase the cruising airspeed.

There are so many parameters to tweak and I'd appreciate some guidance 
for the best way to do this. I assume that I need to adjust (at least) 
two parameters: 1) pitch during level flight, 2) cruising throttle. 
There are several pitch and throttle parameters, so which do I need to 
tweak to do this?

While I'm at it, I have another question: even without the pod, the 
plane tends to overcorrect a bit when navigating (especially when 
turning into the wind). Reducing NAV_PGAIN doesn't help very much. Any 
suggestions for reducing this?

Thank you!

John Burt