2 fatalities

1999-07-23: Piper PA-61 Aerostar (Ted Smith 601) (N345LS) — Mark H. Johnson — Oklahoma City-Wiley Post, United States of America

Oklahoma City-Wiley Post, United States of AmericaTakeoff (climb)

On July 23, 1999, a Piper PA-61 Aerostar (Ted Smith 601) (registration N345LS) operated by Mark H. Johnson was involved in an aviation accident near Oklahoma City-Wiley Post, United States of America during takeoff. 2 people were killed. Investigators recorded the probable cause as: The pilot's failure to maintain the minimum controllable airspeed. A factor was the disconnected rubber interconnect boot, which resulted in the partial loss of left engine power. This summary draws on records from the Bureau of Aircraft Accidents Archives (B3A).

Sourcesthe Bureau of Aircraft Accidents Archives (B3A)Primary reportUpdated 1781204244Data APIEditorial standards

During takeoff, a twin-engine airplane rolled left and impacted terrain after the pilot reported a problem. Witnesses saw black smoke from the left engine, and the interconnect boot on that engine was found disconnected.

Accident Overview

During takeoff, a twin-engine airplane was observed to roll left, pitch nose down, and impact terrain shortly after the pilot reported to air traffic control that he had a problem.

Witness Observations

Witnesses reported that the left engine was producing black smoke during the takeoff roll. One witness stated that the airplane had slowed to approximately 60 to 70 miles per hour prior to rolling to the left.

Maintenance History

A mechanic who worked on the airplane prior to the accident stated that the pilot reported being unable to maintain manifold pressure (MP) with the left engine. The mechanic found that the left engine's rubber interconnect boot, which routes induction air between the turbocharger controller elbow and the fuel servo, was "gaping open." The mechanic reseated the boot and tightened the clamp. The pilot flew the airplane afterward and reported no problems. During a second flight, the pilot reported that the left engine was again unable to maintain MP. Prior to the accident flight, the pilot informed the mechanic that the "hose had slid off again" and that it had been reinstalled and he "felt sure it was o.k." A witness stated that he saw the pilot working on the left engine the morning of the accident.

Accident Site Findings

At the accident site, the left engine's interconnect boot was found disconnected. The clamp securing the boot was not located. No other preimpact anomalies were found with the engines, propellers, turbochargers, or fuel servos.

Probable Cause

The official findings stated that the probable cause of the accident was the pilot's failure to maintain the minimum controllable airspeed. A factor was the disconnected rubber interconnect boot, which resulted in the partial loss of left engine power.