On Fri, 3 Jul 2009 12:58:00 -0500, "William Wixon"
wrote:

i don't know very much about RC aircraft but only one time i was at a RC
airplane get together, some guy was flying his large very expensive RC
airplane and all the sudden he started yelling (screaming) for
someone/everyone to turn off their radio transmitter, apparently someone had
inadvertently gotten onto his frequency and he completely lost control of
his airplane. didn't know that was a hazard for RC airplanes, was an eye
opener. (whoever it was turned off their transmitter in time and the guy
recovered control of his airplane.) wonder if there are now transmitters
that aren't vulnerable to that or if there even might be some sort of
encoded secure transmitters? must be huh for the drones and uav's the
military uses.

b.w.

There are only so many RF frequencies available to use
practically. And there are even fewer legal to use for such
purposes. RF is RF and if the foreign signal (another
controller) is strong enough you will be ****-out-of-luck no
matter what kind of encoding/control scheme is in use.
Another person may not be able to take over control without
the proper signaling scheme but they can effectively jam
your control.

The best defense in a jamming situation would be for your
vehicle to be looking for some sort of "heart-beat" type
pulse. If it is not received in a certain time frame to go
into a programmed shutdown, glide type landing.

--
Leon Fisk
Grand Rapids MI/Zone 5b
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