The NTSB has released factual information for the crash of a Phenom 100 in Gaithersburg, Md., on Dec. 8, 2014, and some of the data points to the likelihood of icing conditions and the fact that the airplane’s anti-icing equipment was not switched on at the time of the accident. The pilot and two passengers (one was sitting in the right front seat) flew from Chapel Hill, N.C., to Montgomery Country Airport (GAI), where the weather conditions were: wind 040 degrees at six knots, visibility 10 statute miles, few clouds at 2,100 feet agl, overcast ceiling at 3,200 feet agl, temperature -1 degree C and dewpoint -8 degrees C.
According to the NTSB Group Chairman’s Factual Report, Operational Factors, “Performance data combined with the weather radar echoes indicated that the accident airplane was in instrument meteorological conditions until approximately one mile from GAI and also in conditions that were favorable for structural icing for at least 10 minutes during the approach. Multiple jet air carriers in the vicinity of the accident site reported icing conditions in the clouds with cloud tops ranging from 4,300 feet to 5,500 feet msl. In addition, four minutes after the accident, there was another pilot report from a regional turboprop pilot who was encountering moderate mixed icing between 4,000 feet and 5,000 feet msl.”
The Operational Factors Report also noted that a full-flaps approach with wing/stab and engine icing protection switched on would have been weight-limited to 8,033 pounds, much less than the calculated approach weight of 8,671 pounds. The Vref at the lower weight/ice-protection-on condition would have been 112 knots. At the higher weight and with ice-protection on, but flaps set to position 3, Vref would have been 121 knots. The flight data recorder showed that the Phenom’s flaps were set to full, with ice-protection off, and in this condition, Vref was 95 knots.
“The final portion of the FDR recorded data depicted the airplane’s approach to GAI,” according to the report. “Performance data indicated that the airplane experienced an aural stall warning at an indicated airspeed of 88 knots. At the time of the aural stall warning the airplane was at an altitude of 803 feet msl and on the final approach to the airport.” Airport elevation is 539 feet.
According to the report, the Phenom pilot experienced an accident while flying a TBM 700 into GAI on March 1, 2010. Afterwards, the pilot was required to take an FAA oral check and flight re-examination. The pilot’s Phenom 100 type-rating training,checkride and recurrent training were conducted entirely in his airplane. He had earlier scheduled the initial type-rating training at the Embraer-CAE Training Services facility, but later canceled the appointment. He had also made an appointment for recurrent training at the Embraer-CAE facility, but canceled that as well.