US National Transportation Safety Board orders inspection of Pratt & Whitney engines

Friday, October 17, 2008, 18:14 by Aviation Correspondent

The United States National Transportation Safety Board (NTSB) has ordered that some Pratt & Whitney aircraft engines be inspected after a Pratt PW2037 engine on a Delta Air Lines jet failed during takeoff in Las Vegas, the United States, on August 6, 2008.

The takeoff of the affected Delta Air Lines jet was aborted safely and there was no fire or injuries to the 166 passengers and crew.

“Pratt engines should be removed from service and inspected when they have accumulated significantly fewer hours of service than the 10,880 hours the engine had in the Las Vegas incident,” the National Transportation Safety Board said in a letter to the United States Federal Aviation Administration (FAA), the agency of the United States Department of Transportation with authority to regulate and oversee all aspects of civil aviation in the US.

The National Transportation Safety Board (NTSB), based in Washington, D.C., is an independent agency of the United States government responsible for investigation of accidents involving aviation, highway, marine, pipelines and railroads. The NTSB also watches over the military, and in case of accidents helps them. The agency is charged by US Congress to investigate every civil aviation accident in the United States, as well as sensational accidents in other modes of transportation. It is also in charge of investigating cases of hazardous waste releases that occur from different modes of transportation.

Pratt & Whitney is a United States-based manufacturer of aircraft engines that are widely used in both civil and military aircraft. Though one of the three biggest  maker of aero-engines – the other two being General Electric and Rolls-Royce – Pratt & Whitney has formed joint ventures with both General Electric and Rolls-Royce. In addition to aircraft engines, Pratt & Whitney, a unit of United Technologies Corporation, makes fixed gas turbines for industry and power generation, marine turbines, railway locomotive engines, and rocket engines.

The NTSB has recommended urgent and stepped-up inspections of certain Pratt & Whitney engines on dozens of passenger jets to detect possible flaws linked to “the most catastrophic type of failure.”

Mark Rosenker, acting chairman of the National Transportation Safety Board, said in a statement: “The NTSB has asked the Federal Aviation Administration to require that PW2037 engines undergo recurring inspections for the time being once they reach a certain point in their operation. Also, preventive safety measures must be taken.”

The action by the NTSB would affect over 700 engines on about 300 Boeing 757 aircraft worldwide, including a number of Boeing 757 planes operated by the United States-based airlines such as Delta Air Lines, United Airlines, Northwest Airlines, and American Airlines.

In aircraft safety parlance, an “uncontained failure” occurs when the engine gives out, and parts are ejected through protective covering. The parts blown through the engine can penetrate the fuselage.

In the case of the Delta Air Lines, investigators found holes in the engine cover as well as damage to the engine turbine. The investigation also revealed missing parts and cracked turbine blades.

The National Transportation Safety Board Additionally also said it had since learned of cracked parts in other PW2037 engines.

In a statement, Pratt &Whitney said the company “is cooperating fully with the Delta Air Lines investigation and is committed to finding the cause of that incident.”