I just read this post... http://diydrones.com/forum/topics/waypoints-and-failsave
CAA rules apparently say... (as of Feb. 2012?) http://www.caa.co.uk/docs/33/CAP658.PDF
Any powered model aircraft fitted with a receiver capable of operating in failsafe
mode should have the failsafe set, as a minimum, to reduce the engine(s) speed
to idle on loss or corruption of signal.
Because of a recent post about a lost fly away quad a design flaw in the APM has come to light wherein the APM holds the last setting (highly unlikely to be idle) upon the loss of throttle signal input. This happens on many receivers when they lose signal or could happen if a signal wire came loose. Apparently this isn't easily changeable behavior and is the normal failsafe mode.
Am I missing something or does this make the APM completely illegal to operate in CAA countries? Hopefully there's some loophole that I missed somewhere.
If you do not want to modify the AC code, then I recommend you:
* obtain or configure your RX for failsafe operation
* configure your modes such that the mode channel for manual is a low PPM value
* configure your RX failsafe to:
* drop the CH5/mode channel to the low/manual PPM value
* drop the CH3/throttle to a low value
There are other options, I suppose, this is just one example, if that is how you interpret the CAA rule.
As the builder and operator, the responsibility is yours, I would think.
of course, you're going to crash your gear a lot more often.... not sure it really adds much to the safety of flying. But its not mine to worry about.... I'm betting the rule makers had fixed wing operation in mind, foremost.
I bet with a quad you could make a decent argument that your hover throttle level is equivalent to "idle". You could probably argue that zero throttle would be the quad equivalent of flooring a car in reverse and not what the law intends.
OTOH, if you're not level and the APM freezes your output then you're not really going to hover and will actually be flying at a good speed under power (and out of control) when the APM doesn't kill your throttle.
Sounds like a legal crapshoot to me, in which case the government just wins by costing you more legal fees than the fine or intimidating people into pleading guilty or just paying the fine.
I think you are right.... in which case, I'd try for an RX failsafe value that matches your position hold mode setting...quite a bit safer, too, if you've set that. Gives you the chance to get nearer.... unless you lost signal because you flew too high.
There also seems to be a lot of confusion with guidelines, rules, directives, etc. here in the US with the FAA. Unfortunately I don't have any real experience dealing with how these things work out legally. Hopefully someone in the know can shed some light on the issue.
Well, my receiver is a simple one that has no failsafe mode....
On a related note, using an APM also means the ability to do Geofencing etc, and there is also the telem link which may still be operable even if your TX/RX is not.
Quadcopters generally don't have engines, nor do any electric aircraft.
If they want you to cut your electric motors to zero power, they should say so.