Product category:
Engineering Education, Resources and Standards
News Release from: ERA Technology
Edited by the Engineeringtalk Editorial
Team on 07 November 2000
ERA helps to identify emergency landing
cause
ERA Technology assisted The Air Accident Investigation Branch with their investigation into the incident on 9 January 1998 when a Boeing 767 was forced to carry out an emergency landing at Heathrow
The Air Accident Investigation Branch (AAIB) released a report on 2 November 2000 on the incident on 9 January 1998 when a Boeing 767 was forced to carry out an emergency landing at Heathrow Airport ERA Technology Ltd, the independent technology consulting company, assisted AAIB with their accident investigation by using a variety of techniques including scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis to identify materials within and adjacent to the failure site
This article was originally published on Engineeringtalk on 3 Sep 2001 at 8.00am (UK)
Related stories
Process availability simulation service launched
ERA Technology has launched an availability simulation service to help owners and operators of process plant achieve optimum performance to maximise returns from investment and long term profitabily
ERA Technology tests 100th Sea Harrier radome
ERA Technology has just tested the 100th Sea Harrier production radome for Chelton Radomes.
ERA's analysis helped to identify the cause of the incident and to reduce the risks of a similar event occurring.
The aircraft was on route for Washington DC from Zurich, when abnormal warnings appeared on the flight deck instrumentation and circuit breakers began tripping.
The commander decided to divert and land at Heathrow.
Further reading
Twist-technology antennas get networks launched
ERA has helped Radiant Networks to realise its broadband wireless mesh terrestrial network service by adapting an ultra-compact antenna, based on novel twist-technology
Programme to focus on RoHS Directive
ERA Technology is offering an opportunity for companies to participate in shaping the only Restriction of Hazardous Substances analysis programme currently under development in Europe.
The aircraft subsequently landed safely, but after it had turned off the runway smoke appeared at the forward end of the passenger cabin.
As a result, the commander ordered an evacuation.
Fortunately there were no casualties but a thorough enquiry had to be conducted.
As part of the investigation ERA carried out SEM/EDX analysis on a number of samples from the aircraft's electronic and equipment bay.
It emerged that the tripping of multiple circuit breakers had been caused by the occurrence of electrical arcing and associated thermal damage to a wiring loom adjacent to a corner of the galley chiller unit within the bay.
This in turn had resulted in thermal damage to an adjacent loom and smoke generation.
The investigations also showed that prior damage to the wiring loom insulation had occurred due to abrasion by the chiller unit during its removal and re-installation.
ERA suggested that although the conductors of the wires in the loom had been exposed by mechanical damage they would not necessarily have arced immediately.
The wires were operating at voltage levels that were insufficient to cause an immediate failure.
It was thought that additional factors such as moisture or conducting matter would have been required on the wire surface to initiate arcing and carbonisation of the insulation.
Further SEM/EDX analysis revealed that aluminium alloy swarf was present within the bay prior to the accident and had probably assisted the onset of arcing between adjacent damaged wires in the loom.
Incorrect installation of the chiller unit, with its heat exchanger exhaust fitted with a blanking plate, would have caused warm exhaust air to discharge from an alternative upper vent which was capable of blowing any aluminium swarf around the wiring looms.
By carrying out this analysis, ERA helped AAIB identify a number of causal factors.
AAIB's enquiry report includes eleven safety recommendations to prevent further similar occurrences.
• ERA Technology: contact details and other news
• Email this article to a colleague
• Register for the free Engineeringtalk email newsletter
• Engineeringtalk Home Page
Search the Pro-Talk network of sites
