SEA93LA173
1993-08-10 · SHERIDAN, Wyoming, United States · None · 1 aircraft · Status: Completed
Airport SHR
Current FAA registration · N116BH
- Make / Model
- PIPER PA-18-150
- Year of manufacture
- 1963 · 30 years old at event
- Engine
- LYCOMING 0-235 SERIES (115 hp)
- Seats / Engines
- 2 seats · 1 engine
- Last airworthiness date
- 19630926
- ADS-B equipped
- Yes — Mode-S A0429E
Source: FAA Aircraft Registry (releasable master file).
Aircraft involved
Probable cause & findings
THE DUAL STUDENT'S FAILURE TO MAINTAIN DIRECTIONAL CONTROL. A FACTOR CONTRIBUTING TO THE ACCIDENT WAS THE INSTRUCTOR'S DELAYED REMEDIAL ACTION.
Factual narrative
On August 10, 1993, at approximately 0715 hours mountain daylight time (MDT), a conventionally geared Piper PA-18-150, N116BH, registered to and operated by Bighorn Airways, Inc., and being flown by Pamela J. Roberts, a certificated private pilot under the instruction of Forrest L. Asmus, an ATP rated flight instructor, sustained substantial damage during a ground loop during landing rollout on runway 31 at the Sheridan County Airport, Sheridan, Wyoming. Neither pilot was injured. Visual meteorological conditions prevailed and no flight plan had been filed. The instructional flight was to have been operated in accordance with the requirements set forth in 14CFR91 and originated at the Sheridan County Airport at approximately 0645 hours. Instructor Asmus reported that pilot Roberts was executing a (main) wheel landing and that as the aircraft decelerated it began to drift right. As the aircraft approached the right edge of the runway pilot Roberts was reported to overcorrect in an attempt to regain control, and the aircraft began a ground loop to the left. The instructor attempted to regain control with the application of full right brake and rudder. However, the ground looped continued and the right wingtip impacted the pavement. The aircraft was subsequently taxied to the ramp. The instructor reported that he was "too slow to correct for improper student control input." Additionally, he reported that there was no mechanical malfunction with the aircraft during the event. DURING THE LANDING ROLL THE DUAL STUDENT ALLOWED THE AIRCRAFT TO DRIFT RIGHT AND THEN OVER CORRECTED IN AN ATTEMPT TO REGAIN DIRECTIONAL CONTROL. AS THE AIRCRAFT BEGAN TO GROUND LOOP TO THE LEFT, THE INSTRUCTOR PILOT ATTEMPTED TO REGAIN CONTROL BUT WAS UNSUCCESSFUL. THE INSTRUCTOR REPORTED THAT HE WAS SLOW TO TAKE CORRECTIVE ACTION. Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12
Verbatim from NTSB's published report. Source file
NTSB_1993_SEA93LA173.txt.
Findings + structured fields enriched from FAA avall.mdb.
Full investigation docket on
data.ntsb.gov ↗.
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