Pratt & Whitney has signed an agreement with the Seven Q Seven group to certificate the JT8D-200 turbofan for re-engined Boeing 707s and, possibly, KC-135 military variants.

The "7Q7" programme could potentially involve the re-engineing of up to 500 in-service 707-320s and KC-135s with the 98kN (22,000lb)-thrust JT8D-219, says the group, which is led by Irish-based Omega Air with partners Ed Swearingen and Douglas Jaffe of San Antonio, Texas.

Although market predictions for the 7Q7 are optimistic, P&W is confident that the programme could generate significant new business for the JT8D line, which looked doomed to closure following Boeing's decision to terminate MD-80 production in 1999.

The first flight of the JT8D-powered 707 is scheduled for the end of this year, with US Federal Aviation Administration certification expected in mid-1999. The engine will be fitted with a modified version of the current MD-80 nacelle, as well as a new, low-emissions, combustor, which is now under test.

The JT8D-200 will replace the original 707-320's JT3D powerplant, providing improved performance, lower fuel consumption and, most importantly, Stage 3 noise compliance at maximum take-off weights.

With the 7Q7 deal, production of the JT8D is therefore likely to continue into the first years of the next century, representing more than 40 years of continuous development since design work began on the engine in 1960, for the Boeing 727.

Source: Flight International