Deciphering Abbreviations

Abbreviation

Description

0SFRM

Zero time since factory remanufacture

OSMOH

Zero time since major (engine) overhaul

COMP

Compression

C/R

Counter-rotating (propellers in twin-engine airplanes)

CSPD

Constant speed (propeller)

CYCLES

In turbine engines, a cycle is from start to full power to shutdown.

FWF

Firewall forward

MDH

Major damage history

MSP

Maintenance service plan

NDH

No damage history

NoFWF

No firewall forward (engine and propeller missing)

OXY

Oxygen system

SCMOH

Since chrome (cylinder) major overhaul

SFRM

Since factory remanufacture

SHS

Since hot section (overhaul of a turbine engine's power compressors)

SMOHA&E

Since major overhaul, airframe, and engines(s)

SMOHRE/LE

Since major overhaul right/left engine

SMOH

Since major (engine) overhaul

SOH

Since (engine) overhaul

SPOH

Since propeller overhaul

STOH

Since top (cylinder, piston, and valve train) overhaul

TBO

Time between (engine) overhaul

TT

Total time

TTA

Total time, airframe

TTAE

Total time, airframe and engine(s)

TTE

Total time, engine

TTSN

Total time since new