Dassault's Falcon 7X business jets, currently grounded because of a stabiliser trim fault, are expected to be airborne again shortly.

Dassault said on 9 June that it had developed and validated a modification, and depending on approvals from the European Aviation Safety Agency and "modification kit logistics", it expects the first aircraft to have the changes completed "within about 10 days".

This modification will feature additional automated protection beyond that already designed into the horizontal stabiliser trim circuitry, the airframer said. Dassault said it involves both software and hardware alterations, which have already been tested and validated on a test bench.

Dassault said it is "co-ordinating an unprecedented logistic effort" to manage the modifications within its own service centres and its Falcon authorised service network, adding that "additional dedicated retrofit lines have been set up in France, at Bordeaux-Mérignac and Istres, and also in Little Rock, Arkansas".

The aircraft have been grounded since an EASA emergency airworthiness directive, issued at Dassault's request, came into effect on 26 May. This followed the 25 May incident when a Falcon 7X experienced a pitch trim event during descent. The crew successfully recovered the aircraft to a stable flight profile and performed an uneventful landing.

The manufacturer says its investigation "has confirmed that the Falcon 7X control laws operated normally, which allowed development of a safe ferry procedure using the digital flight control system in normal mode".

The 7X entered service in 2007, 112 aircraft have been delivered, and until this event they had accumulated over 75,000 fault-free flight hours, said the company.

Source: Flight International