How do I manually start the default Boeing 737 in FSX?

To manually start the default Boeing 737-800 in FSX or FSX: Steam Edition, switch on the battery, start the APU, connect APU electrical power, turn on the fuel pumps and APU bleed air, then select each engine starter to GRD and move its fuel control lever to IDLE at roughly 20–25% N2.

This procedure is for the stock FSX Boeing 737-800. Its systems reproduce the basic 737 starting sequence but omit many protections and checks found in a real 737 or a study-level add-on such as PMDG.

What must be set before starting the FSX Boeing 737-800?

The aircraft needs electrical power, fuel and pneumatic starter air before an engine will rotate.

1. Secure the aircraft: set the parking brake, put both thrust levers at idle and move both engine fuel control or start levers to CUTOFF.
2. Switch on the electrical system: set the battery to ON and standby power to AUTO.
3. Start the APU: move the APU switch to START and release it. It is spring-loaded and should return to ON. Wait until the APU has reached operating speed and generator power is available.
4. Connect APU power: select both APU generator switches so the APU supplies the electrical buses.
5. Configure the fuel system: confirm there is fuel aboard and switch on the pumps for tanks containing fuel. Leave the centre tank pumps off when the centre tank is empty.
6. Configure starter air: set APU BLEED to ON, leave both engine bleed switches ON and turn both air-conditioning packs OFF. Set the isolation valve to OPEN; AUTO may also open it with both packs off, but selecting OPEN removes that uncertainty.
7. Set the beacon: switch on the anti-collision beacon before cranking an engine.

If the cockpit is completely unpowered, follow our full 737 cold-and-dark power-up order before attempting the engine start.

How do I start each engine manually?

Start one engine at a time and do not introduce fuel until its N2 indication is clearly rising.

1. Crank engine 2: move the right ENGINE START switch to GRD. Engine 2 is normally started first, although the default FSX model permits either order.
2. Watch N2: confirm the compressor is turning and allow N2 to reach approximately 20–25%. If it stops below 20%, do not add fuel; correct the bleed-air configuration first.
3. Introduce fuel: move engine 2’s fuel control lever from CUTOFF to IDLE.
4. Confirm light-off: look for rising EGT, N1 and oil pressure. Let the engine stabilise at idle. The starter switch should return from GRD to OFF as the engine accelerates.
5. Start engine 1: repeat the same steps with the left starter switch and engine 1 fuel control lever.
6. Transfer the aircraft services: select both engine generators, return the packs to AUTO and set the isolation valve to AUTO. Switch APU BLEED off, allow the unloaded APU to run briefly, then shut it down.

Configure the hydraulic pumps and complete the remaining before-taxi items rather than assuming that running engines mean the aircraft is ready to move. A downloadable manual and checklist for the default 737-800 covers the rest of that flow.

Why is my FSX Boeing 737 start not working?

The instrument that fails to move usually identifies the missing part of the start sequence: zero N2 means no starter air, while rising N2 without EGT usually means no fuel.

It didn’t work: how do I reset the start?

A clean reset prevents a half-completed start or an inherited controller command from interfering with the next attempt.

1. Cut off fuel: return both fuel control levers to CUTOFF, put the starter switches at OFF and leave the throttles at idle.
2. Let the engines stop: wait for N1, N2 and EGT to settle before trying again.
3. Rebuild the air supply: verify a stable APU, APU BLEED ON, packs OFF and isolation valve OPEN.
4. Test one engine only: select its starter to GRD, confirm rising N2 and then introduce fuel. If the lever moves without your input, correct the controller assignment before continuing.

How do I make the default 737 start cold and dark in FSX?

FSX normally inherits engine and switch positions from the saved flight rather than forcing the Boeing 737-800 into a standard cold-and-dark state.

Shut the aircraft down fully, save that flight and reload it when you want to practise. Our method for saving an FSX flight with its engines off explains how to preserve the required state. Avoid swapping directly from a running piston aircraft, because its starter and mixture settings can carry over to the 737.

Why won’t the PMDG 737 parking brake release?

A PMDG 737 parking brake that will not release is normally a brake-control, axis or wheel-chock problem rather than an engine-start failure.

1. Apply both toe brakes: press the brake pedals firmly. Depending on the PMDG product and realism settings, applying pedal pressure releases the parking-brake lever as on the real aircraft.
2. Check the assigned command: the standard FSX parking-brake command is Ctrl+.. Verify that it has not been removed or assigned to multiple buttons.
3. Inspect the brake axes: a reversed or poorly calibrated toe-brake axis can show continuous braking even when the physical pedals are released.
4. Remove wheel chocks: use the aircraft’s ground-services controls if chocks were fitted. If the parking-brake indication is off but the aircraft still will not roll, also check for an attached tug and a brake axis that remains active.

Do not apply increasing thrust against an aircraft that remains stationary; first establish whether the brake indication is extinguished and the chocks are removed. The stock FSX 737 uses simpler brake logic than PMDG and will usually respond directly to the assigned parking-brake command.

Does this apply to a real 737, FlightGear or a G Major 737 package?

The APU, bleed-air, starter and fuel sequence resembles a real 737 start, but the exact procedure applies only to the default FSX Boeing 737-800.

If the goal is a more complete real-737-style simulation, the default aircraft cannot reproduce every system dependency. Our comparison of the more realistic 737 add-ons available for FSX explains when a study-level model is the better choice.