Engine Flashcards
What kind of engines does the T38 have?
J85-GE-5R/S
8 stage axial flow turbojet
How much thrust per engine?
2200lb at MIL
3300lb at MAX
How much thrust is available at 95% RPM?
50%
When does max continuous thrust occur?
98% RPM
How does the engine start?
Low pressure air is supplied for compressor motoring
How is the engine start powered?
Ignition relay - DC power
Igniter firing - AC power
How long does the static inverter activate when you press the start button?
30 sec
What happens when the throttle is set to idle or above on engine start?
The ignition exciter is energized, firing main and AB igniters and allows fuel to flow to the engine
Can you hold the start button to keep the igniters energized?
Yes
How can the fuel shutoff to the engine?
Throttles - mechanically
Fuel shut off - electrically
Should Idle to mil in less than 1 second be avoided?
Yes, to avoid blade fails
MIL to MAX gives a what percent increase in thrust and a what percent increase in Fuel Flow?
50%, 300%
Above what altitude should you avoid rapid throttle movement?
Above FL350
Nozzle position may indicate less than what percent in AB with less than MAX selected?
50%
What powers the EED?
Right DC
What does FAIL mean on the EED?
Internal failure, use M key to switch modes and possibly use RCP/FCP
What does OFF mean on the EED?
No senor signal
When does the EED notify the MDP about EGT?
When EGT is 655-665 for 60 sec
What happens when the EED overtemps?
display goes down by 50% and EED HOT is displayed for 1 min and the back lights turn off
How does the EED power up on battery power?
Max day brightness regardless of the setting
What happens above FL280 and less than 0.6 Mach?
increased stall susceptibility to stall/flameout due to distorted ram air inflow to engine with lower air density
When does EGT Droop occur?
At low altitude and high airspeed (500 KCAS), EGT may be lower because of the high air flow rate at MIL with less than 3% nozzle indication
When does Idle Decay occur?
During 1 G stalls at or above FL200 with throttles at idle and airspeed less than 200 KCAS the RPM may drop below 46-50% and GEN caution lights illuminate. The engine will not accelerate when throttle is increased.
What RPM should you stay above when flying above FL200 and below 200 KCAS?
80%
