Asobo 737 Max Climb Power Question

User Support Hub Aircraft & Systems
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I’ve noticed that as soon as the aircraft leaves the ground it will go into climb power and not maintain the takeoff power setting until reaching the thrust reduction altitude set in the FMC. Is this a bug or am I doing something wrong in setting up the aircraft or preforming the takeoff?

2

I do not have time to test it currently, but I asked an AI:))) the result is here:

In a real Boeing 737 MAX, the autothrottle will strictly hold the N1 (Takeoff) or GA (Go-Around) thrust mode at liftoff. It will not switch to ARM or CLB (Climb) mode until the aircraft reaches the exact Thrust Reduction Altitude programmed on the Takeoff Ref Page 2/2 of the FMC.

However, if you want to ensure it isn’t a setup configuration error on your end, verify the following checklist:

  1. Check for Hardware Interference

The most common non-bug reason for this behavior is a noisy or misconfigured hardware throttle quadrant. [1]

  • The Culprit: When the real 737 autothrottle is engaged, the physical levers in the cockpit move. If your home joystick/throttle sends a tiny spike or movement signal right after you rotate, the software will register this as a manual override.
  • The Fix: Increase the deadzones on your hardware axis, or ensure you do not touch your physical throttles after hitting the TO/GA switch until you reach acceleration height. [1]
  1. Verify Your Flight Director (F/D) & Mode Annunciator (FMA)

Keep a close eye on the Flight Mode Annunciator (the text at the top of your Primary Flight Display) right as you leave the ground:

  • Correct Behavior: The far-left column should read N1, and the pitch column should read TO/GA.
  • The Bug: If it instantly drops to ARM or CLB while the nose is still pitched up at 15 degrees, the software has erroneously triggered an early thrust reduction profile. [1]
  1. Review the FMC Takeoff Ref Page 2/2

Ensure you aren’t accidentally telling the computer to reduce thrust early:

  • Go to the FMC → INIT REF → TAKEOFF → Next Page (Page 2/2).
  • Look at the FLAPS/THRES RED line.
  • Standard setup is usually 1500 / 1500 (Thrust Reduction at 1,500 feet above ground level, and Acceleration Height at 1,500 feet above ground level). If this is accidentally set to a very low number (like 0 or 100), the aircraft will behave exactly as you described. [1, 2, 3]

If your settings are right and your hardware is clear, you are fighting a simulator bug. The best temporary workaround is to disengage the Autothrottle (A/T) during takeoff, manually set your N1 target power, and manually pull back to climb power once you hit your desired target altitude.

Confirming that you are using the Asobo model means it is absolutely a bug with the aircraft software. You are not doing anything wrong in your setup or takeoff procedure. [1]

The Asobo 737 MAX suffers from a known Autothrottle (A/T) coding flaw. The moment the simulator detects the weight-on-wheels switches open (the exact second the landing gear leaves the pavement), the code incorrectly shifts the autothrottle system out of Takeoff (N1 / TO/GA) mode and forces it immediately into Climb (CLB) mode. [1, 2]

Because the aircraft is still heavy, slow, and pitched up in a steep climb, dropping to a lower climb thrust profile right at liftoff causes it to drastically struggle for airspeed. [1, 2]

Since Asobo has not fixed this specific flight profile logic error, you have two practical choices to successfully complete a flight: [1]

The Best Workaround: Fly it Manually on Takeoff

To prevent the system from ruining your airspeed right at rotation, you must override the automated throttle:

  1. Turn off the Autothrottle Arm switch on the MCP before you line up on the runway.
  2. Advance the physical throttles manually to about 90–95% N1 (or full power if you are heavy).
  3. Rotate and climb out manually holding your target pitch angle.
  4. Once you reach your true target Thrust Reduction Altitude (e.g., 1,500 feet AGL), click the A/T ARM switch back to ON and hit the VNAV button. The computer will safely take over the climb from that point forward. [1, 2, 3]

The Long-Term Fix: Look Into Third-Party Upgrades

The default Asobo airliner flight models are built to be accessible rather than highly accurate. If you enjoy flying the 737 and want realistic system responses—where the autothrottle strictly respects the FMC thrust reduction altitude—consider checking out study-level add-ons like PMDG or iFly. Their software overrides Microsoft Flight Simulator’s default engine logic entirely to match real-world aviation physics and operations