Engineers from American Airlines have closely examined a modified thrust reverser on a Pratt & Whitney JT8D-200 designed by Dugan Kinetics for Boeing MD-80s that could potentially cut fuel burn and reduce noise.

The test aircraft (N789BV) completed functionality and performance testing during 9-12 December at Tucson International Airport, and then flew to American's bases in Tulsa, Oklahoma and Fort Worth, Texas at the carrier's request, says Dugan. American operates around 260 MD-80s, according to Flightglobal's ACAS database.

Dugan has developed a new stow position for the thrust reverser in which the doors are used as an ejector during flight. The new position allows for an increase in thrust while keeping aircraft weight constant.

Duggan Kinetics MD-80 reverse thruster 
 © Duggan Kinetics

By mixing ambient airflow with the jet exhaust, thrust is increased and substantial fuel savings is achieved during climb and cruise through use of the EP-80 Ejector/TR. Dugan has previously said the modified thrust reverser could cut fuel burn per flight from 6% to 12%.

The testing included two baseline flights and two flights with the modified thrust reverser on an MD-8. The duration of the test flights was between 3h and 5h.

Dugan says one of the primary purposes of the testing is to fully understand where the ejector is augmenting thrust to determine a definitive number for fuel burn reduction, and it expects to receive that data from flight engineers soon.

The company also expects to obtain a supplemental type certificate covering the EP-80 Ejector/TR during the later half of the first quarter, says Dugan.

Source: Flight International