Accident Overview
On a flight approaching Hanscom Field in Massachusetts, aircraft N4467X crashed into a house while conducting an Instrument Landing System (ILS) approach to Runway 11. The accident occurred shortly before the aircraft reached the outer marker.
Sequence of Events
After the flight was handed off from Boston Approach Control to Hanscom Tower, an altitude alert for N4467X was received by the Boston Approach radar controller. The controller notified the Hanscom controller, who then informed the pilot of the alert. The pilot responded that he was at 1,400 feet and crossing the outer marker. This was the third instance during the flight where a discrepancy between the barometric altimeter and the encoding altimeter came to light.
Pilot Information
Investigation revealed that the accident occurred at the end of an 18-hour work day for the pilot, who had also been ill with the flu during the weekend preceding the accident.
Investigation
No further details from the investigation have been publicly released at this time. The official investigation continues to examine all aspects of the accident.