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Single engine configuration

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I am trying to figure out single engine configuration of Bell helicopter if one engine is to shut down. The helicopter was flying in following conditions :-

Weight - 10606 pounds

Altitude - 7000 feet pressure altitude

Temperature - 34 degree Celsius

Air Speed - 70 KIAS


According to the OEI performance graph of 11000 weight category given in Rotorcraft Flight Manual the Bell helicopter will get a rate of descend of 370 feet per minute.

My query is that if pilot is flying the helicopter in weight configuration, OAT and altitude given above and has to shut down one engine then what will be the 'single engine configuration' in which pilot has to bring the helicopter before resorting to single engine ?

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I am trying to figure out single engine configuration of Bell helicopter if one engine is to shut down. The helicopter was flying in following conditions :-

Weight - 10606 pounds

Altitude - 7000 feet pressure altitude

Temperature - 34 degree Celsius

Air Speed - 70 KIAS

According to the OEI performance graph of 11000 weight category given in Rotorcraft Flight Manual the Bell helicopter will get a rate of descend of 370 feet per minute.

My query is that if pilot is flying the helicopter in weight configuration, OAT and altitude given above and has to shut down one engine then what will be the 'single engine configuration' in which pilot has to bring the helicopter before resorting to single engine ?

Just saw this. Single engine configuration is just engineer speak for only one engine available and conditions allowed to operate it that way best case (oil temp high/oil press low/chipped the engine/high speed shaft failure/etc or for EP training).

 

Never flew a dual Bell, but it would be same as a Hawk. Torque available most likely goes up, airspeed envelope gets much smaller, etc. Thats your configuration (configured for SE flight...if the aircraft has the power to maintain it...some dont).

Edited by METT-TC

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If that's what the RFM calculation indicates, that's the performance you should expect out of the remaining engine. That's one of many, many reasons why performance planning is an important part of survivable multi-engine helicopter operation.

 

You get to do everything the single engine pilot does to survive and calculate and plan, plan, plan- weights, density altitudes; single engine ceilings; Vx, Vy speeds and takeoff planning- where, how and if you're going to try to fly out or risk junking the other engine; single engine fuel range, etc., etc.

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My query is that if pilot is flying the helicopter in weight configuration, OAT and altitude given above and has to shut down one engine then what will be the 'single engine configuration' in which pilot has to bring the helicopter before resorting to single engine?

If I understand what you're asking, then single engine configuration is simply a power setting at which the engine can operate without exceeding limits. If the pilot was flying at 70% torque dual engine and needed to shutdown one engine and made no power adjustments the remaining engine would have to be able to provide 140% torque to maintain that same flight profile. In most aircraft that is not possible and would require the pilot to reduce power prior to shutting down an engine. Fictional numbers here, but if the max single engine torque available was 120% the pilot would reduce collective to below 60% dual engine prior to pulling a power lever.

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