15. Gas turbine engine - Q&A

zbd: Generally EPR is only used in civil aviation. Reheat is used in the military jet engine. The engine rating (full throttle engine) are used in military jet instead of EPR. Now civil aviation no more using reheat since concord and Tu-144 already grounded.EPR is the ratio of the turbine discharge pressure to the engine inlet air pressure. Reheat event happen downstream of the turbine,so if EPR is used it remains constant.

PART66Online: Hello. FADEC is only a name of system where Electronic Control Unit obtains parameters from many sensors and give commands to some units, one of them is HMU. Please check this schematic: http://2.bp.blogspot.com/_7EMmyqZZDTA/TP0cIol_CBI/AAAAAAAAAQs/VpfhDYNc7bM/s1600/FADEC.JPG

Mhmd: Yes after the desiccant absorbs the moisture in the air it will turn pink. After it turns pink it can not absorb the moisture in air so it is ineffective and it should be replaced with a new one blue color.

Mhmd: Specific gravity changes at altitudes so the hydromechanical governor compensates for the variation in fuel SGs

Mhmd: M.V.P stands for moisture vapour protection. To minize the moisture contant while the engine is in storage

Mhmd: First you should understand how a thermocouple works! It is a combination of two dissimilar metals. So when they are subjected to heat. It will expand at a different rate. This difference of hot and cold section creates a varying voltage proportional to the heat generated, the voltage can be take in to account for example 1 mv = 50 *C 2 mv = 100*c. The system can be calibrated to work in this way. Fire detection is to detect fire or rise in temp. So the best thing is to use here is a thermocouple system. Cheers!!

mwongela: from the choices, the answer can only be A....also got stuck there

mwongela: outside air temperature

malowth: Checked it out. It would appear the word USUALLY is the key word in the question. I have only worked on the one type of Gas Turbine, and while it has a Fuel Heater/Strainer, the primary oil cooling method for that engine is ram air through an oil cooler.I assumed wrongly that this was a standard practice. Thanks for your help.

mwongela: nothing wrong. had selected the wrong question to respond to

mwongela: yeah i have noticed today that the answer has changed. thanx

ketkimapzoom: yes it is

PART66Online: Hey. You wrong. The three phase AC generator sends information to the indicator. Please refer to Jeppesen Aircraft Gas Turbine Powerplants page 12-13.