Over six weeks of tests set for ‘Dash 4’ improvement

Premier Aircraft’s delayed programme to upgrade the Dassault Falcon 50’s Honeywell TFE731 engines to improve the business jet’s performance is back on track, with the test aircraft expected to fly with modified engines at the end of this month. Illinois-based Premier has also booked its launch customer for the Falcon 50-4 upgrade.

Supplemental type certification (STC) of the “Dash 4” performance upgrade, originally expected in February, was pushed back by delays in certificating of the N1 digital electronic engine control on the TFE731-4-1C engine, says Premier president Jim Swehla, and is now expected in late December.

Falcon 50    
Premier Aircraft estimates 240 Dassault Falcon 50's are eligible for upgrade

Some 25h of flight testing to establish the baseline performance of the unmodified aircraft with TFE731-3 engines has been completed, and the -4 engines are now being installed by Premier, Swehla says. The modified Dash 4 aircraft is expected to fly on 30 September, when it will relocate to Mojave, California for certification flight testing by Flight Test Associates.

The 50h of flight testing planned over six weeks will establish the Dash 4’s performance and operability characteristics. Premier is projecting reduced time to climb, higher initial cruise altitude and up to 26% more range as a result of the TFE731-4’s higher climb and cruise thrust and lower specific fuel consumption. Maintenance intervals will also be extended.

The first customer aircraft is planned to be inducted by Premier in December. The engines will be removed, replaced by loaner -3s and sent to Honeywell for upgrade to -4 configuration, which will take six weeks, says Swehla. The aircraft will then return for installation of the modified engines, which will take 10 days, he says.

The Dash 4 upgrade costs $1.6-2.3 million depending on the maintenance status of the existing TFE731-3/3D engines, says Swehla, who estimates there are 240 Falcon 50s worldwide eligible for the upgrade. Premier plans eventually to make its STC available to other authorised service centres, he says.

Source: Flight International