Too much speed in inexperienced
by Bob Violett
travels to 10-12 events per year and through our representatives throughout the
U.S. we have observed or hear about most of the turbine jet crashes.
Many of these crashes could have been avoided
if the speed of the model was dialed down to the experience level of the pilot
and that of the builder of the model.
It takes years of flying and building experience to be able to
safely operate a complex, heavily power loaded turbine model.
The current AMA waiver system allows any
applicant who has filled out the paperwork to operate a high performance jet -
almost without limits. It is basically a license to go 200 mph without actually
demonstrating the capability to do it safely.
Many modelers who are currently entering the
turbine era have limited building and flying experience. In many cases they
have entered the hobby with ARF models that may fly 120 mph at best. These are
light loaded, 4 channel airplanes offering little challenge to assemble and
cannot be bought - it can only be acquired with time and dedication to the
task. The "need for speed" can be satisfied in a safe manner only after
the required experience has been gained.
Doesn't it make sense to utilize the technology of speed limiting
devices or dial down the thrust until the pilot's skills catch up with the
model's ultimate capability?
practical way to do this is to incorporate a throttle-to-throttle mix in your
transmitter, activated by the retract or flap switch, that allows full power
for take-off and then a much reduced setting for flight.
This also facilitates a throttle position more
closely related to model speeds that the pilot is familiar with.
for a BVM Bandit weighing 19+ lbs with RAM 750, AMT AT-180, or Jet-Cat
Take off power - 17 pounds of thrust,
the ultimate top end speed will be approximately 230 to 240 mph.
power - 11 pounds of thrust, the ultimate top end speed will be approximately
to suggest that if the pilot trainee has experience with 120 mph models, then
that should be his limit until stick time and experience justifies
Operating at reduced power
also increases the time to reach the ultimate velocity allowing the
pilot-in-training more time to react to the acceleration.
Throttle management is the single, most
different, required skill for flying a turbine jet. Operation at reduced power
will allow this required skill to be obtained in an orderly and safe
We have observed AMA
turbine waiver approved pilots take off, loose visual orientation, crash and
burn within seconds and they never even pulled the throttle back, proving that
written rules and completed paperwork are not sufficient for safe
Knowing and respecting the
limits of the model and the current skills of the pilot are key to avoiding
these unnecessary, costly and potentially dangerous to our sport, occurrences.
We are all, always in
see a flight of F-18's, F-16's or F-15's fly over, they are either on the way
to, or returning from a "training mission".