B737 flight crew reported momentary loss of aircraft control during taxi out for takeoff.

Date: 2025-06 · Aircraft: B737 Undifferentiated or Other Model · Phase: taxi

Anomalies: deviation-discrepancy-procedural-published-material-policy|ground-event-encounter-loss-of-aircraft-control

Synopsis

B737 flight crew reported momentary loss of aircraft control during taxi out for takeoff.

Narrative

During single engine taxi out of the ramp; we stoped at a spot short of the service road. The spot sits on a relative incline; compared to the ramp. We received our taxi clearance of Taxiway 1-Taxiway 2-XXR. The trainee used the control column toggle down transmit to read back the clearance. This error was recognized and read back on the correct transmitter. When I released the parking brake to taxi; I initially pushed up the number 1 thrust lever by accident. Because of the incline; we began to slowly roll backwards. I immediately pushed up the number 2 thrust lever to about 60%. I lightly touched the brakes; but did not want to induce a tail tip. We had to wait for engine 2 to spool up and provide enough thrust to stop our roll and create forward movement. We probably rolled backwards for 5-10 feet. Fortunately; there was no traffic behind us. I am very familiar with ZZZ and all of its taxiways. It was a mistake that happened at one of the worst places on the airport it could have happened at.

Second reporter narrative

Conducting OE (Operating Experience) training on our ZZZ-ZZZ1 flight. Flaps 5 max power NADP (Noise Abatement Departure Procedure) departure off of XXR; for training. Clearance was climb via the ZZZZZ2 RNAV. At 6300 feet indicated; ATC instructed us to level off at 7000 feet. We were climbing at 2000+ feet per minute; with the expectation of cleaning up at 3000 feet AGL. We were able to level off just fine; however; it really was an unexpected clearance. Our VNAV disconnected with 180 kts in the window; we still had flaps 5 out...it was a strain on our situational awareness to correct the MCP (Mode Control Panel) and comply. We ended up abandoning our NADP plan and cleaned up level at 7; after bugging the clean maneuver speed. We continued at 7000 feet for a couple minutes and were then cleared up to 8;000 feet. ATC told us the level off was because of traffic off of 8 in the west. I don't know what that means. It just happened really fast and caught us by surprise...off all the times to be doing an NADP.

More incidents for this aircraft family →

Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.