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GAA18CA300

2018-05-17 · Killeen, Texas, United States · None · 1 aircraft · Status: Completed

Airport ILE

Aircraft involved

Probable cause & findings

The pilot’s failure to maintain adequate airspeed and his exceedance of the airplane’s critical angle of attack during a maximum performance takeoff, which resulted in an aerodynamic stall. Also causal was the pilot’s failure to use the appropriate flap setting in accordance with the manufacturer’s Maximum Performance Takeoff checklist.

Factual narrative

The pilot reported that, during a max performance takeoff, he set the flaps to 10° and accelerated to 60 mph. He pulled back and pitched the airplane for Vx (best angle climb), 52 mph, to simulate an obstacle, then pitched for Vy (best rate climb), 72 mph, where he observed a rate of descent. He pitched back to gain altitude, but immediately heard the stall warning horn and felt a lack of responsiveness in the flight controls. He leveled the airplane to touch down on the remaining runway, but the right wing and right horizontal stabilizer impacted the runway. The airplane sustained substantial damage to the right wing and right horizontal stabilizer. The pilot reported that the cause of the accident was that the published Vx airspeed is below the stall speed. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation, but that it was possible that the engine was not performing at optimal performance. The airplane owner's manual checklist titled "Maximum Performance Take-Off" states: 1. Wing Flaps – Up. 2. Carburetor Heat – Cold. 3. Brakes – Hold. 4. Throttle – Full "OPEN". 5. Brakes – Release. 6. Elevator Control – Slightly tail low. 7. Climb Speed – 52 MPH (with obstacles head). The manual also states: "Normal and obstacle clearance take-offs are performed with flaps up. The use of 10° flaps will shorten the ground run approximately 10%, but this advantage is lost in the climb to a 50-foot obstacle. Therefore the use of 10° flap is reserved for minimum ground runs or for take-off from soft or rough fields with no obstacles ahead." The manual also states that the stall speed, with 0° angle of bank, is as follows: Flaps Up – 55 mph Flaps 20° - 49 mph Flaps 40° - 48 mph The pilot reported that, during a max performance takeoff, he set the flaps to 10° and accelerated to 60 mph. He pulled back and pitched the airplane for Vx (best angle climb), 52 mph, to simulate an obstacle, and then pitched for Vy (best rate climb), 72 mph, where he observed that the airplane was descending. He pitched back to gain altitude but immediately heard the stall warning horn and felt a lack of responsiveness in the flight controls. He leveled the airplane to touch down on the remaining runway, but the right wing and right horizontal stabilizer impacted the runway. The airplane sustained substantial damage to the right wing and right horizontal stabilizer. The pilot reported that the cause of the accident was that the published Vx airspeed was below the stall speed. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation but that it was possible that the engine was not performing at optimal performance. The airplane owner's manual checklist titled "Maximum Performance Take-Off" stated: 1. Wing Flaps – Up. 2. Carburetor Heat – Cold. 3. Brakes – Hold. 4. Throttle – Full "OPEN." 5. Brakes – Release. 6. Elevator Control – Slightly tail low. 7. Climb Speed – 52 MPH (with obstacles head). The manual also stated:         Normal and obstacle clearance take-offs are performed with flaps up. The use of 10° flaps will shorten the ground run approximately 10%, but this advantage is lost in the climb to a 50-foot obstacle. Therefore, the use of 10° flap is reserved for minimum ground runs or for take-off from soft or rough fields with no obstacles ahead. Source: NTSB Aviation Accident Database Retrieved: 2026-02-12

NTSB Findings

FAA avdata. C = Cause, F = Factor.

  • C Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Angle of attack-Capability exceeded - C
  • C Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Airspeed-Not attained/maintained - C
  • C Aircraft-Aircraft systems-Flight control system-TE flap control system-Incorrect use/operation - C
  • C Personnel issues-Task performance-Use of equip/info-Aircraft control-Pilot - C
  • C Personnel issues-Task performance-Use of equip/info-Use of checklist-Pilot - C

Verbatim from NTSB's published report. Source file NTSB_2018_GAA18CA300.txt. Findings + structured fields enriched from FAA avall.mdb. Full investigation docket on data.ntsb.gov ↗.

Related research

Matched on aircraft type or causal vocabulary (stall). All research papers