"I would not mount it on top of an aircraft unless it has a canopy or some sort of cover over it. Remember there is a barometer inside and depending on how air will be directed internally it could effect or cause issues the the Baro sensor."

"Having your FC off of CG will be an issue
Especially at high speeds. Just for the hell of it,
On one of your other fixed wings move your pixhawk From CG to the same distance as you would on your skyrunner.
Take it out on a calm day and fly it at…"

"For what its worth I would add the Zener and the cap as seen in Wiki. I have seen pixhawk shut down and reboot using digital servos. Remember to power the rail with good clean reliable power because the power that is plunged into the rail is…"

"Paul
Take the props off your aircraft.
Using the latest Mission planner connect to the pixhawk, NOT WITH USB because it will not allow you arm pixhawk so only via radio as you would flying missions.

Boot up pixhawk and connect to MP.
Take a look at…"

"For what its worth, what would you say if they came unplugged in flight and you lost 10 grand in camera equipment.
They are doing what they were designed to do and do it very very well.
I have 5 pixhawks now and have had Zero issues with them and or…"

"I have 2 pixhawks mounted out in open air and have had no issues with loosing altitude. As Ian had suggested, , get some logs to look at. Logs will tell the story.
You did start from a fresh setup and have no mixes involved, I'm sure there isn't but…"

"How much altitude are you losing?
If you were to keep flying forward would it fly itself into the ground?"

"If you're traveling 100 or more miles it's a good idea.. 25 ,50 or so miles isn't a big deal. Personally anything over 50 miles I recalibrate just to be on the safe side..
But that's me."

"Any frequency can be jammed. "

"If you are asking if the RTH will work if they block the Rf, yes the copter will return to home.
Now if you are asking if they jam satellite signals along with Rf or hit them with EMF, , No they will fly away or hit the dirt."

"Steve
You can setup multiple waypoints in mission planner.. you can have hundreds of pre planned missions. Once you get to the area that you want check out..
Open mission planner ,, open saved mission files and pick what ever mission you have…"

"You have to remember that your straight line is limited buy the GPS signal on any given day, including your locations and ground clutter.

Gps does not work as well on the ground as it does in the air.

You also have manometer that will help with…"