ASN Aircraft accident Beechcraft 99 Airliner N986MA Allentown Airport, PA (ABE)
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Status:Accident investigation report completed and information captured
Date:Sunday 24 October 1971
Type:Silhouette image of generic BE99 model; specific model in this crash may look slightly different
Beechcraft 99 Airliner
Operator:Monmouth Airlines
Registration: N986MA
MSN: U- 44
First flight: 1968
Engines: 2 Pratt & Whitney Canada PT6A-20
Crew:Fatalities: 2 / Occupants: 2
Passengers:Fatalities: 2 / Occupants: 6
Total:Fatalities: 4 / Occupants: 8
Aircraft damage: Damaged beyond repair
Location:18 km (11.3 mls) N of Allentown Airport, PA (ABE) (   United States of America)
Phase: Approach (APR)
Nature:Domestic Scheduled Passenger
Departure airport:Wilkes-Barre/Scranton International Airport, PA (AVP/KAVP), United States of America
Destination airport:Allentown-Lehigh Valley International Airport, PA (ABE/KABE), United States of America
Flightnumber: 98
Monmouth Airlines Flight 98 departed Wilkes-Barre at 22:53 for a short IFR flight to Allentown. Allentown Approach Control cleared the flight for a VOR approach and instructed the pilot to report when it was 12 miles North of the Allentown VOR. At 23:07, upon receiving the flight's position estimate, Allentown Approach Control cleared Monmouth 98 for a VOR approach to a landing on runway 06. Monmouth 98 was requested to report when inbound over the Allentown VOR. The Beech then collided with the ridge of Blue Mountain at an elevation of 1540 ft (470 m).

Probable Cause:

PROBABLE CAUSE: "The pilot's nonadherence to approved approach procedures for executing a nonprecision instrument approach in instrument flight conditions. The Board further finds that there is a high degree of probability that the extensive on-duty time and actual instrument flight time prior to this accident resulted in the fatigue of both pilots and affected their judgment and decisions during the approach."

Accident investigation:
Investigating agency: NTSB
Status: Investigation completed
Duration: 66 days (2 months)
Accident number: NTSB/AAR-72-03
Download report: Final report

Insufficient rest / fatigue
Controlled Flight Into Terrain (CFIT) - Mountain

Follow-up / safety actions

NTSB issued 3 Safety Recommendations

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This map shows the airport of departure and the intended destination of the flight. The line between the airports does not display the exact flight path.
Distance from Wilkes-Barre/Scranton International Airport, PA to Allentown-Lehigh Valley International Airport, PA as the crow flies is 79 km (50 miles).
Accident location: Approximate; accuracy within a few kilometers.

This information is not presented as the Flight Safety Foundation or the Aviation Safety Network’s opinion as to the cause of the accident. It is preliminary and is based on the facts as they are known at this time.
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