Loss of Control in Flight · NTSB CEN15LA432
RANS S18 — Shattuck, OK
| Date | September 29, 2015 |
| Location | Shattuck, OK |
| Aircraft | RANS S18 (amateur-built) |
| Purpose of flight | Personal |
| Conditions | Day · Visual Meteorological Cond |
| Phase / occurrence | Enroute-climb to cruise Collision with terr/obj (non-CFIT) |
| Pilot age | 37 |
| Pilot total time | Unknown |
| Time in type | Unknown |
| Fatalities | 1 |
Probable cause
NTSB findings
- Personnel issues-Experience/knowledge-Experience/qualifications-Qualification/certification-Pilot - C
- Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Angle of attack-Capability exceeded - C
- Personnel issues-Task performance-Use of equip/info-Aircraft control-Pilot - C
- Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Airspeed-Not attained/maintained - C
What happened
The noncertificated pilot was conducting a personal flight in the noncertificated experimental, amateur-built airplane. The pilot had flown to the grass airstrip along with two other pilots, who were flying ultralight trike aircraft. One of the trike pilots reported that each pilot conducted two or three landings at the grass airstrip. The two trike pilots then taxied their aircraft to the northeast end of the airstrip to prepare to depart for the final takeoff. The accident airplane was faster than the trikes and departed while the trike pilots were still taxiing, so they did not see the accident airplane again, and no one witnessed the accident. The trike pilot stated that he believed that the accident airplane might have initially departed to the west, that he and the other trike pilot had departed to the southeast, and that it is possible that the accident pilot was turning his airplane to join them when the accident occurred. The airplane wreckage was subsequently located in a nearby field, and it was oriented to the southeast.
The postaccident examination of the wreckage indicated that the airplane impacted terrain in a steep nose-down attitude consistent with a stall/spin. The examination of the airframe, engine, and propeller revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. Further, no evidence was found indicating that any medical conditions or substances contributed to the accident. It is likely that the pilot was turning to the southeast after departure and then failed to maintain airplane control and exceeded the airplane's critical angle-of-attack, which resulted in a stall/spin.