[Usage Statistics]

Engine Designations

For reciprocating engines:

 MVLHGATSIORL 550F
 |||||||||||| |  |
 |||||||||||| |  .->  F: FADEC (Full Authority Digital Engine Control)
 |||||||||||| .---->  The Engine displacement in cubic inches
 |||||||||||.------>  L: Liquid cooled engine
 ||||||||||.------->  R: Radial engine
 |||||||||.-------->  O: Opposed engine.  Other valid letters are:
 |||||||||            I (Inline), V (V-engine), R (Radial), X (X-type)
 ||||||||.--------->  I: Fuel injected
 |||||||.---------->  S: Supercharged (Engine can operate at manifold
 |||||||              pressures above 29.92)
 ||||||.----------->  T: Turbocharged (Engine can maintain rated power
 ||||||               at altitude (up to a certain maximum)
 |||||.------------>  A: Aerobatic engine (inverted oil system, dry sump)
 |||||                AE: Aerobatic engine (inverted oil system, wet sump)
 ||||.------------->  G: Geared engine
 |||.-------------->  H: Horizontal Helicopter engine
 ||.--------------->  L: Left turning engine
 |.---------------->  V: Vertical Helicopter engine
 |.---------------->  M: Drone

For turboprop engines:

  TP 500 ---->  500 shp turboprop

The questions that I have are:

1. How are rotary engines specified, how about wankel engines?
2. Are there more variations for turboprop engines?
3. How are jet engines specified?

Aerobatics website
Soaring website
Landings Aviation Server