Tim,

did you do a range check beforehand? Is your antenna sheilded in some way from receiving the TX signal?

What are your on off switches like? IF they are cheap nasty ones or have dirty contacts that can cause servos to "lock" as they pull current.

If someone had turned on a TX on your freq then yes the plane would be uncontrollable as you describe. Do you fly at a club that uses a freq board with pegs etc?

I'm not sure how the radio spectrum is manged in your country but here each band is specifficaly assigned to users with class licenceces. Though we use mainly 36Mhz and you guys are on 72Mhz it still falls broadly into a HF band.

Here the only users who could interfere would be military.

I would think fire trucks etc would be on UHF freq - around 850 Mhz so they should not be a problem and CB radios are 27Mhz. It is possible for a harmonic freq from a badly out of tune radio to jam your freq but it would need to be very close to you.

I recall in france that some disgruntelted nut got a scanner, copied down all the R/C plane freq of a club who flew near to him and then set up a sweep generator coupled to a linear power amp and TX on that band and systematically shot down every plane he could. He went to jail however.

Best bet is to get a scanner, maybe your association has one and monitor the band at your club and ask if anyone else is having probs.

good luck
Peter