Andes MD83 near Tucuman on Mar 7th 2018, engine shut down in flight

Last Update: December 5, 2019 / 16:15:27 GMT/Zulu time

Bookmark this article

Photo of Andes Lineas Aereas LV-BEG, McDonnell Douglas MD-83 — Andes Lineas Aereas LV-BEG, McDonnell Douglas MD-83 (Photo credit: c38astra / Flickr / License: CC by-sa)

Incident Facts

Date of incident
Mar 7, 2018

Classification
Incident

Cause
Engine shut down in flight

Airline
Andes Lineas Aereas

Flight number
OY-855

Departure
Jujuy, Argentina

Destination
Buenos Aires Aeroparque, Argentina

Aircraft Registration
LV-BEG

Aircraft Type
McDonnell Douglas MD-83

ICAO Type Designator
MD83

An Andes Lineas Aereas McDonnell Douglas MD-83, registration LV-BEG performing flight OY-855 from Jujuy,PJ to Buenos Aires Aeroparque,BA (Argentina) with 156 passenges and 6 crew, was enroute near Tucuman,TU (Argentina) when the crew received an abnormal indication for the right hand engine (JT8D) and decided to shut the engine down. The aircraft diverted to Tucuman where it landed safely on runway 02 about 80 minutes later.

The airline reported the aircraft suffered the loss of pressure on one of the engines, the crew decided to shut it down in order to avoid damage to the engine and diverted to Tucuman for a safe landing about 80 minutes later. A technical team was moved in from Salta, the aircraft is estimated to continue the flight in the afternoon. The passengers have been informed and were served lunch.

On Mar 16th 2018 Argentina's JIAAC reported the crew received indications of decreasing oil quantity and decreasing oil pressure for the right hand engine. The crew declared emergency, shut the engine down and diverted without further incident. The occurrence was rated an incident and is being investigated.

On Dec 5th 2019 Argentina's JIAAC released their final report in Spanish only (Editorial note: to serve the purpose of global prevention of the repeat of causes leading to an occurrence an additional timely release of all occurrence reports in the only world spanning aviation language English would be necessary, a Spanish only release does not achieve this purpose as set by ICAO annex 13 and just forces many aviators to waste much more time and effort each in trying to understand the circumstances leading to the occurrence. Aviators operating internationally are required to read/speak English besides their local language, investigators need to be able to read/write/speak English to communicate with their counterparts all around the globe).

The report connects the occurrence of Jan 27th 2018, see Incident: Andes MD83 near Cordoba on Jan 27th 2018, engine shut down in flight to this occurrence and concludes:

The loss of oil through a pressure pipe, that connect the pressure different switch, resulted in a loss oil pressure in two events, 39 days apart, in the right hand engine of the aircraft.

The loss of oil occurred through a fissure in the exchanger pressure tube as result of fatigue caused by excessive torque values during adjustment of the nut connecting the tube to the switch.

From the starting point of the fissure as result of excessive torque the fissure increased in length during each engine cycle allowing oil to escape.

The last maintenance action recorded took place 3 months prior to the first event during a 2C inspection, when a functional check of the pressure switch was performed on both engines of the aircraft. The task required the disconnection of the oil pressure tube from the switch, the task was performed by the same engineer and inspector on both engines.

When reconnecting the tube the requirements for torque on the nut were not observed.

The technical reference documentation for carrying out that task was not specific and did not warn about the torque on the nut and its value, which is located in the standard practice chapter.

Finding the value of torque on the nut in the standard practise chapter is not easy.

The technical documentation provided by the manufacturer, adjusted by Andes Linhas Aereas and approved by Argentina'S ANAC, has the potential to generate errors such as the one which resulted in the oil pressure tube fissure.

Due to the extremely technical nature of the analysis, which makes it next to impossible to provide any meaningful summary due to language and translation issues, a summary of the analysis is not being provided here.