Loss of Control in Flight · NTSB SEA08LA178

Kolb Mark III — Richland, WA

1 fatal High-time pilot
DateAugust 14, 2008
LocationRichland, WA
AircraftKolb Mark III
Purpose of flightPersonal
ConditionsDay · Visual Meteorological Cond
Phase / occurrenceUncontrolled descent Collision with terr/obj (non-CFIT)
Pilot age72
Pilot total time1,000 hrs · Experienced
Time in type1,000 hrs
Fatalities1

Probable cause

The pilot's failure to maintain an adequate airspeed above stall speed while executing a steeply banked turn in the traffic pattern.

NTSB findings

  • Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Airspeed-Not attained/maintained - C

What happened

Soon after taking off from the paved runway, the pilot of the experimental airplane leveled off about 200 feet above ground level. At that altitude, and long before reaching the departure end of the runway, the pilot began a 180 degree turn that would bring him onto a low-level downwind where he would soon turn base from this very abbreviated traffic pattern. During the turn, the bank angle of the airplane became very steep, and the pilot failed to maintain an airspeed above the increased stalling speed (Vs) in the steep turn. The airplane stalled and descended at a steep angle into the terrain. Examination of the airplane did not reveal any evidence of a structural or flight control malfunction, and there were no anomalies found with the engine. Witnesses at the airport familiar with the pilot and the airplane stated that the pilot flew this abbreviated low altitude traffic pattern often.

An editorial "what led to it / how to avoid it" analysis for this accident is generated separately and will appear here.

View the official NTSB docket →