Welcome Guest. Sign in or Signup

1 Answers

Prop Governor in Single Engine vs Multi Engine

Asked by: 6053 views Aircraft Systems

So, I'm trying to find right answer for this question.
So far I found out that:

In single engine oil pressure for the prop governor will be used when prop need to go to higher pitch (Lower RPM). In case of oil loss prop will be in Low pitch High RPM setting.

In multi-engine, oil pressure for the prop governor will be used when prop need to go to low pitch (higher RPM). In case of oil loss prop will be in feather position for less drag.


Okay so my questions are:

1. Engine can run without prop governor? if so why multi-engine prop needs to be in feather position during loss of oil pressure? because if both engine can run without prop governor, landing will be much easier as long as engine is fine.

2. If engine can not be ran without prop governor, why single engine prop goes into low pitch / high rpm setting during loss of oil pressure? Less drag = farther gliding distance right?

 

Ace Any FAA Written Test!
Actual FAA Questions / Free Lifetime Updates
The best explanations in the business
Fast, efficient study.
Pass Your Checkride With Confidence!
FAA Practical Test prep that reflects actual checkrides.
Any checkride: Airplane, Helicopter, Glider, etc.
Written and maintained by actual pilot examiners and master CFIs.
The World's Most Trusted eLogbook
Be Organized, Current, Professional, and Safe.
Highly customizable - for student pilots through pros.
Free Transition Service for users of other eLogs.
Our sincere thanks to pilots such as yourself who support AskACFI while helping themselves by using the awesome PC, Mac, iPhone/iPad, and Android aviation apps of our sponsors.

1 Answers



  1. Robert Jankowski on Mar 05, 2016

    Yes, an engine can run without a prop governor, tens of thousands of non-complex aircraft flying around are proof of that.

    Loss of oil pressure in a single engine aircraft equipped with a hydraulic propellor governor will result as you said in the prop defaulting to the high RPM position. This is to give the pilot the ability to continue flight in the event of a governor failure, provided the engine is still operational as it would stop spinning if the engine seized from lack of lubrication.

    The multiengine aircraft have something to consider that the single engine aircraft don’t: asymmetric drag and thrust. The loss of an engine on a multiengine propellor aircraft creates quite a bit of yaw if the propellor is windmilling, this coupled with a loss of thrust on that side of the aircraft introduces a significant amount of yaw (caused by loss of thrust and also increased drag on the failed engine), which if not corrected swiftly and correctly could result in the aircraft departing controlled flight. If the propellor is feathered automatically at the sudden loss of oil pressure, that drag is reduced pretty substantially, giving the pilot a better ability to manage the situation.

    There’s also the issue that if the pilot isn’t able to feather the prop on the failed engine before the anti-feathering pins engage, then there’s a pretty good chance the pilot will be stuck with a windmilling propellor all the way thru the flight and landing… Landing with a dead and windmilling engine is not my idea of fun.

    +4 Votes Thumb up 4 Votes Thumb down 0 Votes


The following terms have been auto-detected the question above and any answers or discussion provided. Click on a term to see its definition from the Dauntless Aviation JargonBuster Glossary.

Answer Question

Our sincere thanks to all who contribute constructively to this forum in answering flight training questions. If you are a flight instructor or represent a flight school / FBO offering flight instruction, you are welcome to include links to your site and related contact information as it pertains to offering local flight instruction in a specific geographic area. Additionally, direct links to FAA and related official government sources of information are welcome. However we thank you for your understanding that links to other sites or text that may be construed as explicit or implicit advertising of other business, sites, or goods/services are not permitted even if such links nominally are relevant to the question asked.