History of Flight
On August 21, 2011, about 1800 eastern daylight time, an Aero Commander Callair A-9B airplane, registration N7638V, was substantially damaged when it struck terrain following a glider tow operation at Brooks Field Airport (RMY) in Marshall, Michigan. The pilot was airlifted from the scene in critical condition and succumbed to injuries approximately 7 hours later. The airplane was owned and operated by the Marshall Soaring Club under 14 CFR Part 91. Visual meteorological conditions prevailed, and the flight was not operated on a flight plan. The local flight departed RMY around 1758.
The glider pilot being towed reported a normal takeoff aside from gusty winds. About 15 seconds into the flight, the glider's airspeed began oscillating, with increasing amplitude. During the third or fourth cycle, he encountered a high-intensity thermal and briefly lost sight of the towplane, locating it below and slightly to the right. With high tow rope tension, he released. The towplane appeared stable with wings level, and the glider pilot returned for a landing.
A witness observed a normal takeoff, but noted turbulence near the runway end. The glider appeared to struggle maintaining position, and at one point experienced a tugging motion from slack in the tow rope. After the glider released, the towplane turned right while the glider continued straight. At about 350 feet above ground level, the towplane's right wing dropped, and it entered a 60- to 70-degree nose-down attitude, completing about half a rotation before disappearing behind trees.
The airplane impacted an open field about half a mile west of the departure end of the runway, sustaining substantial damage to the wings and fuselage.
Aircraft and Pilot Information
The airplane was a 1968 Aero Commander Callair A-9B, serial number 1366, with a single-place, single-engine, tailwheel configuration. It held a restricted category special airworthiness certificate for agriculture and glider towing. The engine was a 300-horsepower Lycoming IO-540-K1A5. The most recent annual inspection was completed on June 26, 2011, at 6,833.3 hours total airframe time. The engine had 444.7 hours since rebuild, and the airplane accumulated 27.1 hours since inspection. No unresolved maintenance issues were recorded.
The 59-year-old pilot held an airline transport pilot certificate with multiple ratings, including single- and multi-engine land, seaplane, helicopter, glider, and flight instructor. He also held Boeing 737 and Cessna 500 type ratings. His pilot certificate was issued in October 2010 with the addition of a glider rating. He held a first-class medical certificate issued January 19, 2011, with a near and intermediate vision limitation. A subsequent application on August 3, 2011, was deferred, and a decision was pending at accident time. He reported 31,000 total flight hours, with 325 in the preceding 6 months. His personal logbook showed four entries for 2011, including 2.0 hours in the accident airplane, and one entry on the accident date without duration. According to glider club records, he joined in September 2009 and had about 30 hours in A-9B airplanes and 35 hours in gliders.
The glider pilot held a private pilot certificate with a single-engine land rating (no glider rating) and a third-class medical certificate issued July 20, 2011, with a near-vision restriction. He reported 472 total flight hours, with 4 hours in the previous 6 months. He joined the glider club in June 2011 and had completed 36 glider flights totaling 9.2 hours, including 3.8 hours solo. His initial glider solo was on July 17, 2011. He was fatally injured in an unrelated airplane accident on October 6, 2011, in Holland, Michigan.
Meteorological and Airport Information
At 1800, the RMY Automated Weather Observing System reported wind from 280 degrees at 14 knots, gusting to 19 knots; visibility 10 miles; scattered clouds at 5,500 feet; temperature 23°C; dew point 12°C; altimeter 29.94 inches of mercury.
Brooks Field Airport has a single east-west asphalt runway, 10-28, 3,501 feet long by 75 feet wide. Glider operations were conducted from grass south of the runway.
Wreckage and Examination
The accident site was about half a mile west of the runway departure end. The airplane came to rest upright, oriented north. The forward fuselage was deformed, engine remained attached, both wings partially separated with crushing damage, and flight controls were present except for partial separation of ailerons and flaps. The left aileron remained fully attached.
Postaccident examination revealed no preimpact anomalies. Elevator and rudder control continuity was confirmed. Aileron control damage appeared consistent with overload from impact. The engine exhibited compression on all cylinders, magneto spark, fuel in gascolator and flow divider, clean fuel filter, and operational electric fuel pump. Throttle and mixture controls were continuous. The propeller had one blade undeformed and one bent 90 degrees at the root. The airspeed indicator tested within 2 mph throughout its range.
The 200-foot tow rope was recovered about 400 feet east of the accident site, separated approximately 166 feet from one end; the corresponding tow ring was attached. The remaining rope portion was not recovered.
Medical Information
An autopsy on August 23, 2011, attributed the pilot's death to multiple injuries from the accident. The FAA CAMI toxicology report detected atropine, etomidate, lidocaine, ondansetron, and midazolam (in liver only) in samples, consistent with medical treatment.
Additional Information
The FAA Glider Flying Handbook notes that during aerotow, allowing the glider to rise high above the towplane can lead to loss of sight, excessive tow rope tension limiting elevator authority, and potential inability to release the rope. This situation is critical below 500 feet agl, and the glider pilot must release immediately upon losing sight of the towplane.