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Atlas / NTSB / CEN11CA360

NTSB CAROL · Event

Event CEN11CA360

2011-05-20 Colorado Springs, Colorado, United States Airport · KFLY Serious 1 aircraft Status: Completed

Registry · N566RL

FAA Aircraft Registry record.

Make / Model

LAMMERS SJEF J APACHE

Year of manufacture

2001 · 10 years old at event

Engine

ROTAX 583 (92 hp)

Seats / Engines

2 seats · 1 engine

Last airworthiness date

20100122

ADS-B equipped

Yes — Mode-S A73EB6

Registrant of record

LAMMERS SJEF J

Source: FAA Aircraft Registry (releasable master file).

Aircraft involved

Probable cause & findings

The pilot's failure to maintain control of the aircraft during take-off in a cross wind, which resulted in an inadvertent stall.

Factual narrative

On the morning of the accident, the pilot had removed his single-surface wing and installed a dual-surface wing on his weight shift aircraft. The winds were calm and he conducted an uneventful test flight. The pilot returned to his hanger and made some adjustments to the control bar but elected to not do another test flight because the winds were increasing at the airport. Later that afternoon, the pilot decided to do a second test flight because the wind had decreased some. The pilot departed with an 80 degree crosswind between 5 and 10 knots. He said that he did not build up sufficient airspeed on the takeoff roll and once he got airborne he was about 5 knots above stall speed and very slow. When the aircraft was approximately 100 and 150 feet in the air, he encountered wind shear and the right wing stalled and dropped. The pilot was unable to recover and the aircraft crashed on the right side of the runway, resulting in substantial damage to the entire aircraft. On the morning of the accident, the pilot had removed his single-surface wing and installed a dual-surface wing on his weight shift aircraft. The winds were calm and he conducted an uneventful test flight. The pilot returned to his hangar and made some adjustments to the control bar but elected to not do another test flight because the winds were increasing at the airport. Later that afternoon, the pilot decided to do a second test flight because the wind had decreased some. The pilot departed with an 80 degree crosswind between 5 and 10 knots. He said that he did not build up sufficient airspeed on the takeoff roll and once he got airborne he was about 5 knots above stall speed and very slow. When the aircraft was approximately 100 feet in the air, he encountered wind shear and the right wing stalled and dropped. The pilot was unable to recover and the aircraft crashed on the right side of the runway, resulting in substantial damage to the entire aircraft. Source: NTSB Aviation Accident Database Retrieved: 2026-02-12

NTSB Findings

Hierarchical cause / factor breakdown from the FAA bulk avdata database. Each finding tagged C (Cause) or F (Factor).

  • C Personnel issues-Action/decision-Action-Incorrect action performance-Pilot - C
  • C Environmental issues-Conditions/weather/phenomena-Wind-Crosswind-Ability to respond/compensate - C

Verbatim from NTSB's published report. Source file NTSB_2011_CEN11CA360.txt. Findings + structured fields enriched from FAA avall.mdb. Full investigation docket on data.ntsb.gov ↗.

Related research

What the literature says.

Academic papers and agency reports matching this event's aircraft type or causal vocabulary (wind shear, stall). Sourced from NASA NTRS, NTSB Safety Studies, FAA CAMI, AOPA Air Safety Institute, Embry-Riddle Scholarly Commons, arXiv, and the Semantic Scholar academic graph.

Browse the full corpus — academia portal ↗