jymil
11th Feb 2013, 19:31
I've just compared the limitations of the AS350 B2 with classical "steam gauges" with the B2 VEMD version and I was a bit surprised to find out the engine limitations are differing, even though the same engine is fitted.
The differences are (classical vs VEMD):
Ng transient: +6 vs +1
Ng takeoff: 0 w/o bleed, -0.6 w/bleed vs 0
Ng max continuous: -3.5 vs -4.0
t4 transient: not defined vs 870°C for 5 sec
torque transient: 107% for 10sec vs 107% for 5 sec
Does anyone know why these limits differ ? Of course, anything transient should only be used in case of emergency (or to avoid a hot section inspection for momentary excursions into the red territory) , but at least the difference in Ng limits strikes me as pretty significant.
The differences are (classical vs VEMD):
Ng transient: +6 vs +1
Ng takeoff: 0 w/o bleed, -0.6 w/bleed vs 0
Ng max continuous: -3.5 vs -4.0
t4 transient: not defined vs 870°C for 5 sec
torque transient: 107% for 10sec vs 107% for 5 sec
Does anyone know why these limits differ ? Of course, anything transient should only be used in case of emergency (or to avoid a hot section inspection for momentary excursions into the red territory) , but at least the difference in Ng limits strikes me as pretty significant.