WPR11CA338
2011-07-15 · Adelanto, California, United States · Serious · 1 aircraft · Status: Completed
Airport 0CL1
N84AM has since been reassigned. It is now registered to a different aircraft (CUBCRAFTERS INC CC11-160, built 2023), which was not involved in this event.
Aircraft involved
Probable cause & findings
The pilot's incorrect use of the flap control pitch control recovery which resulted in an aerodynamic stall.
Factual narrative
The pilot reported that he was turning the glider from base to final at about 400 feet with full flaps and spoilers extended. On final about 100 feet above the ground, the pilot decided to change his flap setting from 20 degrees to 10 degrees as there was a cross wind. When he went to move the flap handle, the handle slipped from his hand and instantly changed the flaps to 10 degrees, which caused the glider to lose lift and nose down. The pilot then pulled back on the controls which caused the glider to stall and collide with the ground. The glider was substantially damaged and the pilot was seriously injured during the accident. The pilot reported no pre-impact mechanical malfunctions of failures with the airframe or the engine that would have precluded normal operation. The pilot reported that he turned from the base leg to final approach at about 400 feet with full flaps and spoilers extended. On final approach about 100 feet above the ground, he decided to change the flap setting from 20 degrees to 10 degrees as there was a crosswind. He said that as he tried to move the flap handle, the handle slipped from his hand and instantly changed the flaps to 10 degrees, which resulted in the glider losing lift and nosed down. He pulled back on the controls, but the glider stalled and collided with the ground resulting in substantial damage. The pilot reported no preimpact mechanical malfunctions or failures with the airframe or the engine that would have precluded normal operation. Source: NTSB Aviation Accident Database Retrieved: 2026-02-12
NTSB Findings
FAA avdata. C = Cause, F = Factor.
- C Personnel issues-Task performance-Use of equip/info-Aircraft control-Pilot - C
- C Personnel issues-Action/decision-Action-Incorrect action selection-Pilot - C
- C Aircraft-Aircraft structures-Wing structure-Trailing edge flaps-Unintentional use/operation - C
- C Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Pitch control-Incorrect use/operation - C
Verbatim from NTSB's published report. Source file
NTSB_2011_WPR11CA338.txt.
Findings + structured fields enriched from FAA avall.mdb.
Full investigation docket on
data.ntsb.gov ↗.
Search this event elsewhere
External sources are reported, not agency: signal that something happened, not fact about what happened.
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Related research
Matched on aircraft type or causal vocabulary (stall). All research papers
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- Embry-Riddle Scholarly Commons 2021 · Journal article (JAAER) Analysis on the Negative Emotional, Physiological, and Cognitive Responses Elicited from of the Activation of a Stall Alarm
Failing to identify an aerodynamic stall can lead to the inability of an aircraft to sustain flight. To warn pilots of an impending or fully-developed stall, many aircraft have safety devices installe…