engine pressure ratio (EPR)

ступінь підвищення тиску в двигуні

reduction ratio / gear ratio

Voltage Standing Wave Ratio (VSWR) / voltage standing-wave ratio

jam to signal ratio (J/S ratio)

engine capacity / engine power, engine output

base pressure ratio

pressure ratio controller

reference pressure ratio

compressor pressure ratio (CPR)

reaction engine / motor (jet engine)

rotary engine (Wankel engine)

engine ground run / engine test

engine oil reservoir / engine oil tank

airbreathing jet engine / ducted jet engine

fighter-to-administrative personnel ratio

high expansion-ratio

power-to-weight ratio

signal-to-noise ratio (SNR; S/N)

thrust-to-weight ratio

attenuation ratio

weight-horsepower ratio

weight-strength ratio

depression ratio

explosion ratio

infantry-armor ratio

forward gear ratio

fuselage fineness ratio

compression ratio