Bird strikes and airplane engine safety debated

Posted in Birdstrike News on Jul 8th, 2009 | no responses

June 11, 2009

A federal hearing is told that it’s ‘not reasonable’ to expect engines to survive any size bird strike. The inquiry is the result of US Airways Flight 1549, which was forced to land in the Hudson River.

Reporting from Washington — It is “not reasonable” to expect airplane engines to withstand any magnitude of bird strike, a federal safety expert said Thursday, urging a concerted effort to prevent incidents like the one that forced US Airways Flight 1549 to land in the Hudson River in January.

In its final day of hearings into the accident, in which the Airbus A320 lost thrust in both engines after hitting a flock of Canada geese, the National Transportation Safety Board debated engine safety requirements as it related to bird strikes.

Robert Ganley, who oversees engine and propeller standards for the Federal Aviation Administration, said that when the turbine-powered engine model on Flight 1549 was certified in the 1990s, it met requirements that it withstand a collision with up to a 4-pound bird or several smaller ones.

The FAA has since revised the standards, in 2000 and 2007, so that the same engine tested today would be required to ingest a bird weighing 6 pounds.

Tests found remains of Canada geese, which typically weigh about 8 pounds, in both of Flight 1549’s engines. The presence of male and female DNA in one engine indicated that at least two birds were ingested. At least one bird hit the other engine.

Bird strikes are increasing each year, officials said.

To avoid accidents like Flight 1549, Ganley suggested an approach that would combine wildlife management, avoidance tactics and revised aircraft certification standards.

Les McVey, a flight safety investigation engineer for CFM International, a jet engine company, said tests revealed that one of Flight 1549’s engines shut down while the other continued working at a lower thrust, performing as expected.

Harry Reichel, an aerospace engineer with the NTSB, asked the FAA if it had considered requiring protective devices for turbine engines.

Marc Bouthillier, an FAA aerospace engineer, said mesh screens would probably accrue ice, which could prove catastrophic for a large turbine engine. Furthermore, screens would reduce airflow.

“The detrimental effects outweigh the positive,” McVey said.