August 21, 2019
By Tim Hepher
LONDON (Reuters) – Investigators probing an engine explosion on an
Air France A380 in 2017 are studying a possible manufacturing flaw in a
recently salvaged cracked part in a move likely to trigger urgent checks
on dozens of Airbus superjumbos, people familiar with the matter said.
The focus of a two-year-old investigation into the mid-air explosion
over Greenland, which left the plane carrying more than 500 passengers
with the front of one engine missing, has switched to the recently
recovered “fan hub,” the people said.
The titanium alloy part is the centerpiece of a 3-metre-wide fan on
engines built for the world’s largest airliner by U.S.-based Engine
Alliance, co-owned by General Electric <GE.N> and United
Technologies unit Pratt & Whitney <UTX.N>.
It had sat buried in Greenland’s ice sheet since September 2017 when
one of four engines on Air France flight 66 abruptly disintegrated en
route from Paris to Los Angeles. It was prised from the ice in June
after a high-tech aerial radar search.
Confirming the focus of the probe after Reuters reported the plans
for inspections, France’s BEA air accident agency said it had discovered
a “sub-surface fatigue crack” on the recovered part and the engine
maker was preparing checks.
The people familiar with the matter linked the crack to a suspected
manufacturing flaw and said the checks – to be carried out urgently on
engines that have conducted a certain number of flights – would affect
dozens of the double-decker jets.
The people said the suspect part was fabricated on behalf of
consortium member Pratt & Whitney, which declined to comment.
Engine Alliance is one of two engine suppliers for the Airbus A380 in competition with Britain’s Rolls-Royce <RR.L>.
Its engines power a total of 152 aircraft or just over 60 percent of the 237 A380s in service.
Besides Air France, other airlines operating the A380 with Engine
Alliance powerplants include Dubai’s Emirates, Qatar Airways, Abu
Dhabi-based Etihad and Korean Air.
The checks will involve taking some planes out of service outside their usual maintenance schedules, one source said.
Investigations are not complete and are likely to tackle other
features such as the loads or physical forces at play. Experts say air
accidents are rarely caused by isolated factors.
Europe’s Airbus <AIR.PA> declined to comment.
SIOUX CITY REMEMBERED
Nobody was hurt in the September 2017 incident, in which the Air France superjumbo diverted safely to Goose Bay in Canada.
Although rare, uncontained engine failures, in which shrapnel capable
of puncturing the fuselage exits an engine at extremely high speeds,
automatically raise alarm.
The checks come weeks after relatives marked 30 years since an engine
failure left a United Airlines DC-10 with almost no control,
culminating in the death of 111 out of the 296 people on board during an
attempted landing at Sioux City, Iowa.
U.S. investigators cited a defective titanium alloy part and weak
inspection procedures, although they also praised the “highly
commendable” performance of the crew of flight 232.
The July 1989 crash sped up improvements in manufacturing methods for
titanium alloy. Experts say hidden internal defects in such parts are
unusual but remain difficult to detect.
Titanium alloy is used widely in aerospace, which is the metal’s
biggest customer due to its strength compared to the weight of each part
and its ability to handle high temperatures.
https://www.oann.com/exclusive-checks-seen-on-some-airbus-a380s-after-2017-engine-explosion/
