2003–The NTSB cited the flight instructor’s inadequate supervision of the flight of Grand Aire Express’s Falcon 20 N183GA, while practicing ILS approaches in IMC with low clouds and rime ice, for causing the airplane to crash. The Board also noted “his failure to maintain an approach airspeed consistent with the airplane’s configuration, which resulted in an aerodynamic stall due to slow airspeed and subsequent uncontrolled descent into trees. Factors were the icing conditions, the flight instructor’s failure to turn on the wing and engine anti-ice and his lack of experience as an instructor pilot.”
The instructor, acting as pilot-in-command and flying from the left seat, was the company’s chief pilot/check airman/designated flight instructor. A first officer in training occupied the right seat. On the second approach to Toledo Express Airport, the airspeed decreased from 188 knots to 141 knots at the outer marker and continued to decrease to 106 knots, when the airplane entered an abrupt descent and disappeared from radar. The airplane struck trees and burned 1.57 nm from the approach end of the runway. The two pilots and a passenger were killed and the aircraft was destroyed.
In a simulator re-creation of the flight, with a power reduction inside the outer marker and a quarter-inch of ice on the wings, the airplane stalled about two miles from the end of the runway with an airspeed of 103 knots.
The instructor had about 1,100 hours in make and model but no documented previous flight instruction experience in any multi-engine airplane. The first officer, who was training for his second-in-command checkride, was the first student the PIC had taken through the initial second-in-command course.
On approach, the PIC acknowledged the arrival controller’s instruction to contact tower; no further transmissions were received and radar contact was lost. A witness reported that she could hear a popping noise as the Falcon passed overhead. As the airplane disappeared, she thought she heard a power reduction. A second witness reported that the tree tops, which were 80 to 100 feet high, were obscured by fog. The engines were running intermittently, interspersed with “bangs.” A third witness reported hearing a noise, “like a huge drum of nuts and bolts, and you shook it. It was very, very loud and then silence.”
A pilot of an airplane following the accident airplane reported light to moderate rime ice, but no ice buildup. Another pilot reported rapidly building rime ice. Five pilot reports listed light to moderate rime ice. Temperature was 0 degrees C dew point -1 degree C and surface visibility 1.75 miles.
Another Grand Aire Express Falcon 20 crashed three hours later when both engines flamed out on approach to Lambert-St. Louis International Airport (STL). That accident, in which two pilots were injured, is still under investigation by the NTSB.
PIPER PA-46-310P MALIBU, OSTENN, FLA., JUNE 14, 2002–Trying to thread through a hole in an area of thunderstorms on an IFR flight from Raleigh, N.C. to Marco Island, Fla., the pilot of Malibu N9143B asked ATC for a deviation 12 miles to the west. He attempted to fly through an area of light radar echoes between the two large areas of heavier echoes. N9143B departed level flight, and radar showed that a cluster of Level Three to Four thunderstorms was present in the vicinity of its position. The airplane started an uncontrolled descent from FL260. Witnesses reported hearing the engine make a winding noise, then the airplane came out of the clouds about 300 feet above the ground, in a nose-low spiral, with the right wing missing. The right wing was found 1.62 miles from the main wreckage.
The NTSB determined the probable cause was the pilot’s inadequate weather evaluation and his failure
to maintain control of the airplane after entering an area of thunderstorms, resulting in the in-flight separation
of the right wing and right horizontal stabilizer and an uncontrolled descent.
The pilot had received a weather briefing, which the NTSB said did not thoroughly address hazardous weather along the route. He had contacted Flight Watch en route and was advised of “cells” east of St. Augustine and of a convective sigmet in effect for southern Florida.
Radar data indicated the airplane descended rapidly in a left-hand turn to a maximum descent rate of 20,700 fpm. The radar pod and wing panel separated at an altitude of 26,000 feet just before the airplane’s rapid descent.
The airplane was destroyed and the private pilot and two passengers were killed. The fracture in the right wing piece and left horizontal stabilizer spar appeared to be caused by excessive upward aerodynamic loads. Initial failure was in compression buckling along the upper surface of the wing.
The pilot’s flight instructor said the pilot “pushed himself dangerously close when making weather decisions in this class of airplane” and seemed to “lack a healthy respect” for the destructive forces of thunderstorms and seemed to take “delight” in how close he could push the envelope. The CFI said he had cautioned him as late as “two weeks” before the accident that his decision-making in this respect was deficient and he needed to exercise “greater care” when flying his converted Malibu (retrofitted with a Pratt & Whitney Canada PT6A-34 turboprop engine) in and around “adverse weather systems.”
(The factual report on this accident appeared in the June issue of AIN.)