Narrative:
A Boeing 767-36N, registration N768NA, operated by Omni Air International experienced a tail strike during landing on runway 29 at Kabul International Airport (KBL), Afghanistan. The flight originated at Bucharest International Airport (OTP), Romania and was operated as a non-scheduled charter.
The landing reference speed for the approach was 145 knots. Due to the gusty weather conditions, the flight crew added 10 knots to this for their approach speed and conducted a visual approach using the visual approach slope indicator as guidance. The airspeed fluctuated during the approach between 162 knots and 138 knots and engine thrust varied accordingly between about 86% N1 and 40% N1 on approach.
The captain stated that the flight was on speed and glide path at 500 feet above the ground but at about 200 feet above the ground, the flight started to move above the glide path and airspeed started to increase. To compensate, the captain reduced engine power and then heard a "sink rate" aural alert when passing through about 50 feet. Flight recorder data indicated the engine N1 decreased to 40%, with throttles at forward idle position, at about 110 feet above the ground, and remained there until after touchdown. The airplane touched down at 140 knots and a nose up pitch attitude of 8.9 °, increasing to 9.5° immediately after touchdown.
Guidance included in the operator's training manuals indicated that normal touchdown attitude should be between 4 and 6 degrees nose up. Additionally, guidance indicated that thrust should be managed on approach to maintain reference speed, plus any wind additive, until the beginning of the flare. After reaching the flare, thrust levers should be retarded smoothly to idle with main gear touchdown ideally occurring simultaneously with thrust levers reaching idle.
An analysis of calculated vertical and horizontal wind effect indicated an existing updraft transitioned to a downdraft and a headwind component transitioned to a tailwind component during the last 5 seconds prior to touchdown.
Probable cause: "The early reduction of engine thrust that resulted in an excessive sink rate and nose high pitch attitude during the landing flare. Contributing to the accident was a significant change in the vertical and horizontal wind components just prior to touchdown."
Runway mishap
FDR flight parameters during approach
| Status: | Accident investigation report completed and information captured |
| Date: | Friday 20 June 2014 |
| Time: | 19:37 |
| Type: |  Boeing 767-36NER |
| Operator: | Omni Air International |
| Registration: | N768NA |
| MSN: | 29898/754 |
| First flight: | 1999-06-05 (15 years ) |
| Total airframe hrs: | 44687 |
| Engines: | 2 General Electric CF6-80C2B7F |
| Crew: | Fatalities: 0 / Occupants: 16 |
| Passengers: | Fatalities: 0 / Occupants: 65 |
| Total: | Fatalities: 0 / Occupants: 81 |
| Aircraft damage: | Substantial |
| Aircraft fate: | Repaired |
| Location: | Kabul Airport (KBL) ( Afghanistan)
|
| Phase: | Landing (LDG) |
| Nature: | Domestic Non Scheduled Passenger |
| Departure airport: | Bucharest-Henri Coanda International Airport (OTP/LROP), Romania |
| Kabul Airport (KBL/OAKB), Afghanistan |
A Boeing 767-36N, registration N768NA, operated by Omni Air International experienced a tail strike during landing on runway 29 at Kabul International Airport (KBL), Afghanistan. The flight originated at Bucharest International Airport (OTP), Romania and was operated as a non-scheduled charter.
The landing reference speed for the approach was 145 knots. Due to the gusty weather conditions, the flight crew added 10 knots to this for their approach speed and conducted a visual approach using the visual approach slope indicator as guidance. The airspeed fluctuated during the approach between 162 knots and 138 knots and engine thrust varied accordingly between about 86% N1 and 40% N1 on approach.
The captain stated that the flight was on speed and glide path at 500 feet above the ground but at about 200 feet above the ground, the flight started to move above the glide path and airspeed started to increase. To compensate, the captain reduced engine power and then heard a "sink rate" aural alert when passing through about 50 feet. Flight recorder data indicated the engine N1 decreased to 40%, with throttles at forward idle position, at about 110 feet above the ground, and remained there until after touchdown. The airplane touched down at 140 knots and a nose up pitch attitude of 8.9 °, increasing to 9.5° immediately after touchdown.
Guidance included in the operator's training manuals indicated that normal touchdown attitude should be between 4 and 6 degrees nose up. Additionally, guidance indicated that thrust should be managed on approach to maintain reference speed, plus any wind additive, until the beginning of the flare. After reaching the flare, thrust levers should be retarded smoothly to idle with main gear touchdown ideally occurring simultaneously with thrust levers reaching idle.
An analysis of calculated vertical and horizontal wind effect indicated an existing updraft transitioned to a downdraft and a headwind component transitioned to a tailwind component during the last 5 seconds prior to touchdown.
Probable Cause:
Probable cause: "The early reduction of engine thrust that resulted in an excessive sink rate and nose high pitch attitude during the landing flare. Contributing to the accident was a significant change in the vertical and horizontal wind components just prior to touchdown."
Accident investigation:
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Classification:
TailstrikeRunway mishap
Photos
FDR flight parameters during approach
Map
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 Bucharest-Henri Coanda International Airport to Kabul Airport as the crow flies is 3785 km (2366 miles).
Distance from Bucharest-Henri Coanda International Airport to Kabul Airport as the crow flies is 3785 km (2366 miles).
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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