Preliminary Report: Cessna 425 breaks up in flight

 - May 19, 2008, 8:13 AM

CESSNA 425, SAN JOSE, CALIF., MARCH 6, 2002–“Just lost my needle…give me…” was the last transmission controllers heard from the pilot of a Corsair (Conquest I) climbing through 8,000 ft. Preliminary reports suggest the pilot experienced a loss of control in IMC that caused the Corsair’s in-flight breakup. Henry “Hank” Guenther, the 62-year-old instrument-rated pilot, and his two passengers died in the crash.

The flight departed the Reid-Hillview Airport in San Jose at 1029 PST and was en route for La Paz, Mexico. After takeoff, ATC cleared the pilot to 13,000 ft and vectored him to join V-485. Following the brief broadcast at 8,000 ft, radar data showed the Corsair began a series of erratic turns, including a 180-deg turn, while the mode-C transponder indicated a descent to 7,100 ft followed by a climb to 8,600 ft. Several smaller descents and climbs preceded a descent through 7,000 ft and the last radar return at 4,100 ft.

A ground witness, interviewed by investigators, reported hearing a loud “screaming” jet sound. She described the aircraft’s descent from the clouds as a “corkscrew pattern.” She then saw it climb in the same kind of turn before she heard a loud bang “she characterized as sounding like an explosion or gunshot.” The witness then saw the aircraft roll level and continue in an “arcing horizontal spin” before it disappeared beyond a hill. Investigators heard from other ground witnesses playing on a nearby golf course, who saw parts falling from the aircraft as it descended.

Investigators found the aircraft in an area over one-quarter mile. The main wreckage and the right wingtip were farthest apart. All control surfaces and their counterweights were found at the accident scene. Preliminary weather reports showed cloud tops at 9,500 ft and the freezing level at 6,000 ft.

Written accounts said Guenther was a volunteer pilot with Los Medicos Voladores, a humanitarian group that sends doctors from the U.S. to Mexico to treat patients without charge. This flight was apparently for pleasure, and the two passengers on board were friends of the pilot.