Accident Boeing 747-357 TF-ARS,

ASN Wikibase Occurrence # 321751

Date:	Tuesday 25 March 2008
Time:	08:27
Type:	Boeing 747-357
Owner/operator:	Saudi Arabian Airlines
Registration:	TF-ARS
MSN:	22996/586
Year of manufacture:	1983
Total airframe hrs:	99327 hours
Cycles:	18779 flights
Engine model:	Pratt & Whitney JT9D-7R4G2
Fatalities:	Fatalities: 0 / Occupants: 325
Aircraft damage:	Substantial, written off
Category:	Accident
Location:	Dhaka-Zia International Airport (DAC) - Bangladesh
Phase:	Landing
Nature:	Passenger - Non-Scheduled/charter/Air Taxi
Departure airport:	Madinah-Mohammad Bin Abdulaziz Airport (MED/OEMA)
Destination airport:	Dhaka-Zia International Airport (DAC/VGZR)
Investigating agency:	RNF
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
Saudi Arabian Airlines flight 810, a Boeing 747-300, was a scheduled flight from Madinah (Saudi Arabia) to Dhaka (Bangladesh).
The flight from Madinah and the landing at Dhaka was uneventful. During the landing roll, approximately 50 seconds after touchdown, the flight crew received a call from the tower controller where the tower controller inquired whether the aircraft was under control. The flight crew responded to the call by stating that the aircraft was completely under control and asked what the problem seemed to be. The controller then informed the flight crew that fire was observed at the right wing area. At this point the Aerodrome Fire Operator had already activated the fire fighters as well as the rescue team. As soon as the controller had informed the flight crew about the fire, the flight crew received a No. 3 engine fire alarm. The co-pilot immediately discharged the first engine fire bottle and the flight crew requested fire fighter assistance and shut down all engines. The co-pilot waited 20 seconds until the second fire bottle was discharged. At this time the commander called the senior cabin attendant to the flight deck using the public address system (PA). This command was followed by a command to the cabin crew to remain seated. The commander informed the senior cabin attendant of the situation and instructed him to evaluate the situation and to evacuate the passengers if necessary. The senior cabin attendant went back down to the main deck and saw the smoke and the fire through the windows. He then commanded the cabin crew as well as passengers, by using a megaphone, to evacuate the aircraft. The cabin attendant at location L2 had already operated the emergency exit and started evacuating the passengers. Cabin attendants at locations L1 and R2 also operated their respective emergency exits. After realizing that smoke and fire were at the right hand side, the emergency exit at R2 was blocked by one of the cabin attendants. All passengers managed to evacuate without serious injuries and the fire department at Zia International Airport managed to extinguish the fire successfully.
The damage to the aircraft was later evaluated as beyond economical repair.

Findings as to causes and contributing factors
- Incorrect assembly of the flexible half coupling at the front spar of engine No. 3.
- Retaining ring missing in flexible half coupling at the front spar engine No. 3.
- Lock wire fastened in such a way that the coupling nut might rotate slightly.

Accident investigation: