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charliegolf
16th Feb 2010, 22:42
Can someone give me a quick explanation of why that is in a Herc. Of course I should know. But I don't. Ta.

CG

Would 4 each thrust and pitch be anywhere near?

OmegaV6
16th Feb 2010, 23:05
Nope .... :)

4 are "condition levers" - Feathered, Ground Stop, Run, Air Start

4 are "throttles" - which actually have 2 ranges built in, ground range and flight range. In the ground range they select a blade angle ( the coarser the blade angle the more air is moved the greater the thrust) and the FCU gives the correct amount of fuel to correspond. This gives very acurate ground manouvering power, including reverse ability. In the flight range the engines run at a constant speed. Throttle increase will cause the engine to try and accelerate, the propellor will then coarsen to "absorb" that effect by taking a larger "bite" of air, so increasing thrust and maintaining constant speed. One of the main advantages is almost instant power as there is no "spool up" time

HTH

Bullethead
16th Feb 2010, 23:08
G'day CG,

The four levers which are close together are the power levers and moving them changes the power the engines develop, the four more widely spaced levers to the right of them are called condition levers and are used for startup, shutdown, airstart and feathering the engines, changing the condition of the engine.

Pitch control and rpm control are automatic.

The Herc engines run at 100% rpm most of the time, there is a low speed ground idle setting, and are self governing.

Regards,
BH.

P.S. Beaten to it by a speedy Omega V6

Buster Hyman
17th Feb 2010, 00:28
Buy one, get one free promotion? :confused::confused::confused:

charliegolf
17th Feb 2010, 09:30
Thanks guys (or gals, if appropriate), even Buster!

The term 'condition lever' was there in the cobwebbed memory, but not close enough to the surface.

CG