GTG START SEQUENCE

12,780 RPM

Diffuser 5th and 10th stage B/A valves CLOSE ENGINE OVERSPEED circuit energized

12,225 RPM

ENGINE RUNNING light illuminates HIGH VIB CIRCUIT energized ENGINE UNDERSPEED circuit energized ENGINE OVERTEMP circuit energized LOSS OF FUEL circuit energized

14,340 RPM

Engine running at NORMAL operating speed.

2400 RPM ( SPEED INCREASING UNDER STARTER POWER)

Fuel Manifold valves energized CLOSE Fuel Shut off valves energized OPEN Air Assist panel ENERGIZES Ignition exciter energized ON FAIL TO FIRE circuit energized

Loss of Fuel

Fuel pressure at fuel manifold is below 60 PSIG above 12,225 RPM.

Start OVERTEMP

If TIT is more than the specified limits at a speed below 12,225 RPM. The specified limits change from 1,600 Deg F to 1,725 Deg F as the speed changes.

9100 RPM

Start Air Valve Close Starter DISENGAGE

Fail to Fire

TIT is less than 600 Deg F within 10seconds after the engine speed is 2,400 RPM

Slow start

The rate of acceleration after light off is <40 RPM/sec for 3 seconds at a speed between 2,400 RPM and 12,225 RPM OR If the speed does not get to 2,400 RPM within 30 second after start button is pushed.

7500 RPM

Air assist Panel DE_ENERGIZED Ignition exciter energized OFF First diffuser B/A valves CLOSED

0 RPM

5th, 10th, and Diffuser B/A valves open AUX L/O Pump cycles for 15 seconds Start air valves opens (Starter ENGAGE) Fuel Manifold Drain valves are energized open Fire Dampner opens START OVERTEMP circuit energized SLOW START circuit energized

Start Automatic shut down

1. Slow start 2. Start overtemp 3. Fail to fire 4. Loss of fuel