Accident Overview
On a day with visual meteorological conditions, a Piper PA-31-350 Navajo Chieftain (registration N27944) operated by Patuxent Airways, Inc., and a Piper PA-44-180 Seminole (registration N2225G) operated by Hortman Aviation Services, Inc., collided in flight over Burlington Township, New Jersey. Both aircraft were destroyed in the accident.
Occupants and Qualifications
Aboard the Navajo Chieftain were an airline transport pilot, a commercial pilot, and seven passengers. The Seminole carried a flight instructor and a private pilot. All 11 individuals were killed. The flight crews of both airplanes were properly certificated and qualified in accordance with applicable Federal regulations. No personal problems or rest anomalies that would have affected their performance were identified.
Aircraft Condition
Both airplanes had undergone required inspections, and examination of maintenance documents showed compliance with all appropriate airworthiness directives. Wreckage examination revealed no evidence of in-flight fire, bird strike, or structural or mechanical failure in either aircraft.
Pilot Toxicology
Tissue samples from the pilot of the Seminole indicated the presence of doxylamine, a sedating antihistamine with substantial adverse effects on performance. However, the amount of blood available was insufficient to determine when the medication was ingested or whether performance was impaired.
Visibility Study
A partial cockpit visibility study determined that the Seminole would have been visible to the pilots in the Chieftain for at least the 60 seconds before the collision. No stereo photographs from a Seminole cockpit were available to determine precise obstruction angles, but due to the relative viewing angle, the Chieftain would have been visible to the Seminole pilots for most of the last 60 seconds. Approximately 4 seconds before impact (about 0.11 nautical miles separation), the angular width of each airplane in each pilot's field of vision was approximately 0.5 to 0.6 degrees, equivalent to about 1/4 inch apparent size at the windscreen.
Official Probable Cause
The probable cause of the accident was the failure of the pilots of the two airplanes to see and avoid each other and maintain proper airspace separation during visual flight rules flight.