3.3.12 PERIODICAL RISE AND DROP IN ENGINE RPM AND MAP
Possible automatic regulation of the system due to airbox temperature limit
1. Carburettor heater - check pushed
2. Throttle - reduce to 65% or below if practicable to allow
quicker cooling
If variations continue after more than 30 seconds,
3. TCU switch - off
4. Continue flight adjusting power regarding OAT conditions and monitor
engine parameters
NOTE
Normal air intake turbo heat rise is between 15°C at idle and 50°C at Full
Power at ISA conditions. Maximum airbox temperature before regulation
is 88°C. Leaving carburettor heater on with high power settings or flying in
elevated OAT can lead to reach quickly the airbox temperature limit.
To Next Page
