Pratt & Whitney
Pratt & Whitney’s GTF geared-turbofan engines entered into service with the A320neo family, and are in place for four other aircraft platforms. According to the engine builder, the GTF is the only engine powering the full range of new regional and single-aisle aircraft series.NEWS
UTX chairman explains the cause and solution to a component failure on geared-turbofan engines
Robert Brooks | Feb 21, 2018
Pratt & Whitney has resolved the error in its PW1000G GTF engines that caused four engines installed in Airbus A320neo aircraft to experience unplanned shutdowns in late January and early February. Those incidents caused the European Aviation Safety Agency to issue an emergency airworthiness directive regarding the engines.
EASA announced it had examples of “several occurrences of engine in-flight shutdown” and other in-service incidents with the PW1100G engines.
In addition, Airbus SE halted all deliveries of the A320neo narrow-body jets featuring the PW1100G geared-turbofan engine.
Speaking to an investors conference, chairman/CEO Greg Hayes of United Technologies, P&W’s parent company, explained that the engine builder had returned to installing a previous version of a knife-edge seal attached to thePW1000G’s high-pressure compressor aft hub. With that fix, Pratt & Whitney resumed PW1000G production in mid-February.
A newer design for the seal had been introduced into new-production GTF engines in December. It was among more than a dozen engineering changes to the PW1000G engines, but according to Hayes the revised seal “did not play out as expected,” according to published sources.
An official statement by Pratt & Whitney explained that “the solution is based on a design with which the company has significant experience.”
The A320neo is a revised version of the A319, A320, and A321 twin-engine aircraft with a “new engine option” (either the CFM International LEAP-1A or the Pratt & Whitney PW1100G), and large wing tips that help to reduce the jets’ fuel consumption.
Airbus selected the PW1100 as the launch engine for the A320neo (new engine option) aircraft family, based on its fuel efficiency, noise reduction, and lower CO2 and NOX emissions.
BoeingTo date, Southwest Airlines has taken delivery of 31 737 MAX jets – making it the largest operator for Boeing’s best-selling aircraft.NEWS
Special panel has found fault with the U.S. agency’s review of the troubled aircraft’s safety system during the 2017 certification process
Oct 13, 2019
The difficulties surrounding Boeing’s 737 MAX aircraft’s airworthiness have put a spotlight on the Federal Aviation Administration’s practices for certifying commercial aircraft. A specialty panel was commissioned by FAA in April to conduct a Joint Authorities Technical Review (JATR) of the agency’s oversight and approval of the 737 MAX flight-control software.
The aircraft was approved for commercial service in 2017. In the past year, two 737 MAX jets were involved in fatal crashes, leading to a global idling of the 385 aircraft still in service with carriers around the world.
The particular concern is the 737 MAX’s Maneuvering Characteristics Augmentation System (MCAS), or “anti-stall” software, which Boeing has determined is the cause of two fatal crashes.
The JATR is chaired by Christopher Hart, former National Transportation Safety Board chairman, and includes air-safety regulators from the U.S., Australia, Brazil, Canada, China, the European Union, Indonesia, Japan, Singapore, and the United Arab Emirates.
According to the JATR report, “MCAS was not evaluated as a complete and integrated function in the certification documents that were submitted to the FAA.
The report further noted that the FAA had too few staffers overseeing the Boeing 737 MAX certification. “The lack of a unified top-down development and evaluation of the system function and its safety analyses, combined with the extensive and fragmented documentation, made it difficult to assess whether compliance was fully demonstrated,” the report continued.
Recently, investigators from the U.S. Office of Special Counsel assigned to review the FAA’s approval of the 737 MAX program (based on a whistleblower’s charge that the agency had not been thorough in its evaluation process) said FAA staff overseeing Boeing’s training standards were unqualified for that assignment.
Boeing has not commented on the JATR report, but reasserted its commitment “to working with the FAA in reviewing the recommendations and helping to continuously improve the process and approach used to validate and certify airplanes.”
Regulatory bodies in Europe, Brazil, and elsewhere continue to scrutinize the proposed software changes and training revisions Boeing is proposing in order return the 737 MAX to service.
Boeing’s software redesign reportedly will incorporate data from two flight-control computers rather than one. However, that update has yet to be approved by the FAA, and Boeing has yet to undertake the effort to reprogram the affected aircraft now suspended .
Follow us:2019 Informa USA, Inc.,
All Rights Reserved