jetcareers - View Single Post

ananoman · September 22nd, 2004, 22:01

You guys did pretty good. I have just a few minor notes.
[ QUOTE ]

Aircraft piston engines are commonly referred to by a series of letters and numbers. What do they refer to in the following examples?
O-320, IO-360, LO-360, R-4360, GSIO-480, GTSIO-520, AIO-360, AEIO-540, V-1710

O = opposed, I = fuel injected, R = radial, G = gear reduction, T = turbocharged, A = aerobatic, V = vee=type. The numbers are the displacements in cubic inches. L = ?

[/ QUOTE ]

The only one you guys missed is the 'S' for supercharged. If there is a 'TS' the engine is Turbosupercharged , if there is only an 'S' the engine is Supercharged by a gear driven supercharger. (The commonly used term 'turbocharged' is really a shortened form of turbosupercharged, which is the correct term, even though few now use it.)

As others have mentioned 'L' is commonly used to denote counter clockwise rotation. There was also an engine put out by Continental that was liquid cooled and I believe this was also referred to as 'L'. The only thing that keeps this from getting confusing is that the liquid cooled engines were only used on some RAM conversions of the big Cessna twins and the Extra 500, which was not a sales success.

As far as I know there are two variations of the aerobatic Lycomings. The older AIO-360 used a dry sump oil system. The newer AEIO series is a wet sump without an external oil tank.

I am still wondering how to denote an inline engine. In cars they usually use an 'L', but this will not help us here.

[ QUOTE ]
Why would an aircraft use an inverted engine? (The D.H. Chipmunk is a good example)

Typically to improve visibility over the cowl.

[/ QUOTE ]

This is true, but the main reason is prop clearance. On an inline or 'V' type engine the crankshaft is normally at the bottom of the engine. To get enough ground clearance, you would have to have abnormally long landing gear, and conventional gear would be mandatory. By turning the engine upside down, the crankshaft and the prop are moved higher away from the ground.

September 22nd, 2004, 22:01	#5
ananoman Senior Member Join Date: Dec 2002 Posts: 916	Re: More worthless trivia! You guys did pretty good. I have just a few minor notes. [ QUOTE ] Aircraft piston engines are commonly referred to by a series of letters and numbers. What do they refer to in the following examples? O-320, IO-360, LO-360, R-4360, GSIO-480, GTSIO-520, AIO-360, AEIO-540, V-1710 O = opposed, I = fuel injected, R = radial, G = gear reduction, T = turbocharged, A = aerobatic, V = vee=type. The numbers are the displacements in cubic inches. L = ? [/ QUOTE ] The only one you guys missed is the 'S' for supercharged. If there is a 'TS' the engine is Turbosupercharged , if there is only an 'S' the engine is Supercharged by a gear driven supercharger. (The commonly used term 'turbocharged' is really a shortened form of turbosupercharged, which is the correct term, even though few now use it.) As others have mentioned 'L' is commonly used to denote counter clockwise rotation. There was also an engine put out by Continental that was liquid cooled and I believe this was also referred to as 'L'. The only thing that keeps this from getting confusing is that the liquid cooled engines were only used on some RAM conversions of the big Cessna twins and the Extra 500, which was not a sales success. As far as I know there are two variations of the aerobatic Lycomings. The older AIO-360 used a dry sump oil system. The newer AEIO series is a wet sump without an external oil tank. I am still wondering how to denote an inline engine. In cars they usually use an 'L', but this will not help us here. [ QUOTE ] Why would an aircraft use an inverted engine? (The D.H. Chipmunk is a good example) Typically to improve visibility over the cowl. [/ QUOTE ] This is true, but the main reason is prop clearance. On an inline or 'V' type engine the crankshaft is normally at the bottom of the engine. To get enough ground clearance, you would have to have abnormally long landing gear, and conventional gear would be mandatory. By turning the engine upside down, the crankshaft and the prop are moved higher away from the ground.