Dolomiti AT72 at Munich on May 17th 2012, smoke in cockpit, engine problem, runway excursion on landing
Last Update: August 8, 2020 / 14:33:57 GMT/Zulu time
Incident Facts
Date of incident
May 17, 2012
Cause
Runway excursion
Aircraft Registration
I-ADCD
Aircraft Type
ATR ATR-72-200
ICAO Type Designator
AT72
The aircraft was piloted by the captain (42, ATPL, 7,804 hours total, 5,559 hours on type) and the first officer (35, ATPL, 4,477 hours total, 1,677 hours on type). The aircraft had accumulated 18,521 hours total in 18,712 cycles.
The BFU reported that upon arrival of the investigators both propellers were found in their feathered positions, the left hand propeller could be turned by hand, the right hand propeller could not be moved. The lower part of the right engine's cowling was covered with oil, the upper part of the right engine's cowling showed burn marks. When the cowling was opened traces of fire and a number of fractured pipes in the aft area of the engine were discovered.
In the cockpit both oxygen masks had been used, the throttles could not be moved.
The right hand engine was sent for laboratory examination.
After the aircraft was moved into a hangar the rudder system was examined, it was determined the pedals could only be moved in a restricted range. The Travel Limited Unit (TLU) was found in the "high speed" mode limiting the rudder travel. After the limiter had been mechanically disconnected the pedals could be freely moved and the rudder followed accordingly to its mechanical stops.
After the battery was connected the TLU was electrically tested, it was found the TLU fault indication was illuminated. There was no "low speed" indication, the bus tie connector switch was found in the open position. When the TLU was manually selected to low speed, the TLU fault indication extinguished and the green low speed indication illuminated about 25 seconds later, the TLU mechanics was moved removing the rudder travel limits. When the TLU was selected to high speed, the mechanism moved to engage the travel limits and the TLU fault indication illuminated 25 seconds after the switch was engaged.
The electrical busses were subsequently powered by a ground power unit, the TLU selected to automatic. With the bus tie still disengaged, the TLU was in high speed mode, the FLT CTL indication was missing, the low speed indication was missing, the TLU fault indication was illuminated. When the bus tie connector was closed the TLU moved to the low speed mode, the low speed indication illuminated and the TLU fault indication extinguished.
The investigation is continuing.
On Aug 5th 2020 the BFU released their final factual report in German and subsequently also in English.
The final report terminates the investigation with the factual narrative only, no conclusions or analysis was released.
The report changes the number of minor injuries to 6 (in the bulletin of 2012 5 minor injuries had been reported), the injuries occurred as result of the evacuation.
The right hand engine suffered the fracture of a turbine blade of the 2nd stage due to stress overload. An inclusion of aluminium, chrome and titan most likely was the point of origin of the fracture. The fracture caused secondary fractures at supply tubes of bearings 6 and 7 resulting in an oil leak, which contaminated the cabin air and caused a fire in the right hand engine. The fire was extinguished with the activation of the fire suppression system.
Incident Facts
Date of incident
May 17, 2012
Cause
Runway excursion
Aircraft Registration
I-ADCD
Aircraft Type
ATR ATR-72-200
ICAO Type Designator
AT72
This article is published under license from Avherald.com. © of text by Avherald.com.
Article source
You can read 2 more free articles without a subscription.
Subscribe now and continue reading without any limits!
Read unlimited articles and receive our daily update briefing. Gain better insights into what is happening in commercial aviation safety.
Send tip
Support AeroInside by sending a small tip amount.
Related articles
Air India Regional CRJ7 at Kanpur on Jul 20th 2011, overran runway on landing
India's Directorate General of Civil Aviation released their final report concluding the probable cause of the incident was:The commander while…
Newest articles
JSX E145 at Houston on May 3rd 2024, gear collapse and runway excursion on landing
A JSX Embraer ERJ-145, registration N942JX performing flight XE-284 from Dallas Love,TX to Houston Hobby,TX (USA) with 21 passengers and 3 crew on…
Avia Kyrgyzstan B733 at Bishkek on May 4th 2024, bird strike
An Avia Traffic Company Kyrgyzstan Boeing 737-300 on behalf of Tez Jet Airlines, registration EX-37020 performing flight K9-117 from Bishkek to Osh…
Subscribe today
Are you researching aviation incidents? Get access to AeroInside Insights, unlimited read access and receive the daily newsletter.
Pick your plan and subscribePartner
A new way to document and demonstrate airworthiness compliance and aircraft value. Find out more.
ELITE Simulation Solutions is a leading global provider of Flight Simulation Training Devices, IFR training software as well as flight controls and related services. Find out more.
Your regulation partner, specialists in aviation safety and compliance; providing training, auditing, and consultancy services. Find out more.
AeroInside Blog
Popular aircraft
Airbus A320Boeing 737-800
Boeing 737-800 MAX
Popular airlines
American AirlinesUnited
Delta
Air Canada
Lufthansa
British Airways