Accident Boeing 737-3M8 OB-2036-P,

ASN Wikibase Occurrence # 319900

Date:	Tuesday 28 March 2017
Time:	16:28
Type:	Boeing 737-3M8
Owner/operator:	Peruvian Airlines
Registration:	OB-2036-P
MSN:	25071/2039
Year of manufacture:	1991
Total airframe hrs:	62817 hours
Cycles:	44025 flights
Engine model:	CFMI CFM56-3B2
Fatalities:	Fatalities: 0 / Occupants: 149
Aircraft damage:	Destroyed, written off
Category:	Accident
Location:	Jauja-Francisco Carlé Airport (JAU) - Peru
Phase:	Landing
Nature:	Passenger - Scheduled
Departure airport:	Lima-Jorge Chávez International Airport (LIM/SPIM)
Destination airport:	Jauja Airport (JAU/SPJJ)
Investigating agency:	CIAA
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
Peruvian Airlines flight 112 from Lima-Jorge Chavez International departed at 16:03 (local time) on a short domestic flight to Jauja Francisco Carlé Airport in Peru.
After a normal flight, the aircraft started the approach in good weather conditions to runway 31 at Jauja Airport. That day, according to NOTAM CO510/17, maintenance work was being carried out on the runway and only the right side was available.
The landing at the Jauja Airport was made by the First Officer, who was in the qualification stage to operate to high altitude airports. After the contact of the main landing gears and two seconds after the nose gear had touched down, almost simultaneously with the activation of the reverse, the crew felt strong vibrations and oscillations accompanied by pitching up and down. The aircraft bouncing a couple of times in an uncontrolled way and after a loud noise, the right main landing gear collapsed. The crew was unable to maintain directional control of the aircraft because the wheels of the left main landing gear and engine No. 2 moved off the runway on the right side. The engine entered a drainage channel and separated. A fuel spill that ignited, reaching the aircraft that had already stopped.
The pilot simultaneously activated the three "Engine Fire" switches and ordered the evacuation of the aircraft from the left side. He ordered the co-pilot to leave the cockpit, as a large amount of smoke was entering. The crew proceeded with the emergency evacuation. No injuries were recorded among the occupants, but the aircraft was de stroyed as a result of the fire.

CAUSE (translated from Spanish)
Failure of the mechanical components of the 'SHIMMY DAMPER - SD" system in each of the main landing gears of the B737-3M8 aircraft, registration number OB2036P, which, being out of tolerance range, did not allow the correct damping of the vibrations and lateral oscillations of the wheels, generating sequential 'SHIMMY" events in both gears, which resulted in their collapse and breakage, while landing at Francisco Carlé de Jauja Airport

CONTRIBUTING FACTORS
1) Incorrect and probable absence of measurements on mechanical components of the "CIMATIC CHAIN FOR SD OPERATION", as indicated by the operator's PM AMM Task, which would have allowed for the timely detection and replacement of out-of-tolerance components, ensuring their integrity and correct operation.
2) The Service Letter 737-SL-32-057-E "BROKEN TORSION LINK", does not provide for mandatory actions, it only recommends maintenance practices to prevent fractures in mechanical components of the "CIMMETIC CHAIN FOR SD OPERATION".
3) Service Letter 737-SL-32-057-E "FRACTURES in LOWER Torsion Link", makes a proper interpretation difficult; that could induce errors to choose the corresponding AMM Task and determine its scope.

Accident investigation: