Does the Discovery Channel travel beyond the States?
On Episode 49: Cell Phones on Planes of the Mythbusters
they examined this problem.
(
http://dsc.discovery.com/fansites/my...9/episode.html)
If I remember correctly, they had a very difficult time
getting any measurable impact on the avionics of both
a mock-up GA and a fairly modern small jet. Since it's
impossible to exhaustively test all possible combinations
of aircraft and cell phones, it appears to be a case of the
FAA being very conservative.
If you are having problems with engine control in an
EC135, why don't you have problems in your BMW?
(Automotive technology more robust than aviation
technology?
)
--Shaun