Altitude Engine

[JonJohn82]

In the FARs it is said you must have a Manifold Pressure Gauge if you have an "altitude engine." What exactly constitutes an "altitude engine"? What is the difference between an altitude engine and any other engine?

 

[146guy]

I don't have much time but look in FAR Part 1 for the definition. That should take care of your question. Also look up Sea level engine.

 

[avbug]

14 CFR 1.1 provides the definition for "Sea level engine," and for "altitude engine."

Sea level engine means a reciprocating aircraft engine having a rated takeoff power that is producible only at sea level.

Altitude engine means a reciprocating aircraft engine having a rated takeoff power that is producible from sea level to an established higher altitude.

Simply put, a normally aspirated engine might be assumed to be a sea level engine, while a boosted engine (turbocharged, supercharged, turbocompound, etc) may be said to be an altitude engine. However, this is not always the case.

A normally aspirated engine that is flat rated or derated will also constitute an altitude engine, as it can produce the same power at higher altitudes than sea level. This engine need not be boosted. A normally aspirated engine of say, 150 horsepower, flat rated for 90 hp max continuous, will continue to produce that 90 hp at higher altitudes. Therefore, even though it is normally aspirated, it is still an altitude engine, and requires a manifold pressure in order to keep the engine within limitations during the climb.

 

[JonJohn82]

Thanks a ton for your help folks!

 

[DAS at 10/250]

Thank you AvBug. He is the only one on this thread to correctly reference the code of federal regulations pertaining to Aeronautics and Space.

There are no FARS in aviation. The "FARS" acronym refers to Title 48, Federal Acquisition Regulations Systems.

Title 14, Aeronautics and Space, is properly referenced as 14 CFR XXX.XX as per AvBug's post and NOT FAR XXX.XX.

If your instructor is teaching you "FAR" correct him/her of their evil ways.

http://www.gpoaccess.gov/ecfr/

 

[146guy]

o.k. buddy!

 

[JonJohn82]

What does the "S" in FARS stand for? "Seatbelts?"

 

[avbug]

Yep...but every time I point that out I'm surprised how many folks get bent out of shape about it.