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So far I came across
1800hp Take Off
1500hp at 2500m
I kinda have tough time understanding the graphView attachment 578947View attachment 578948Between 1942 and 1944, due to the occupation of France, development of the 12Z continued in Spain (Barcelona).
The engine was then announced for 1,800 hp at takeoff, 1,500 hp at 2,500 m. and 1,300 hp at 6,500 m, with a single-stage, 2-speed supercharger.
In 1945, development resumed in France and, initially, the same performances were announced. But these will never be achieved and 2-speed supercharger was abandonned. After type-tests, the 12Z-15 and 16 as well as 12Z-17 and 18 were approved with the performances given by these tables (dated December 31, 1947).
The 12 Z 17 & 18 were identical but turned in opposite directions. The 12 Z 15/16 were 17/18 specially designed to be mounted in tandem on the Arsenal VB10 aircraft.
All had a single speed Turbomeca (Planiol-Szydlowski) supercharger, ratio 8.31 / 1.
How come the take off power works up until 7000 metresDecollage = take off
Surpuissance momentalle = short-term (emergency) power. It is NOT equivalent to WER, since it involved both over-revving and over-boosting; basically, equivalent to the German 'Notleistung' term.
Regime nominal - normal (power) setting.
Croissiere max. - maximum contiuous (power setting).
At Bretoal's graph, there is note 'vitesse d'avion nulle' = 'speed of aircraft = zero', ie. no ram.
I would guess that the "take-off" power is somewhat equivalent to the US MIlitary power.How come the take off power works up until 7000 metres
How come the take off power works up until 7000 metres
I would guess that the "take-off" power is somewhat equivalent to the US MIlitary power.
Some engines were limited to 1-5 minutes at take-off power, many early WW II American engines were operated at the take-off power settings for their military rating (same rpm and manifold pressure)
Note the very particular curves, where power is almost unchanged between SL and critical altitude. I think this was due to the (very particular too !) Turbomeca supercharger, identical to 12 Y's, but modified and very improved.