The grounding of Learjet 45 business jets has entered its fourth week after Bombardier delayed delivery of a data package to the US Federal Aviation Administration for recertification of the horizontal-stabiliser actuator assembly (Flight International 26 August-1 September).

The company says it delayed delivery of the data package because some test results "were not satisfactory", indicating there were issues with materials used in the screwjack actuator that controls the pitch of the horizontal stabiliser, and is supplied by MPC Products of Skokie, Illinois. Bombardier says it plans to submit the recertification data package "as soon as possible, but we are not taking shortcuts".

The delay means Bombardier is now covering half the cost to operators of chartering alternative aircraft while their Learjet 45s remain grounded, up from 25% in the first week following the 13 August airworthiness directive (AD) that grounded the fleet.

Under the alternative lift scheme, operators can book up to 10h charter a week up to a maximum rate of $2,800/h through Bombardier's Skyjet charter brokerage subsidiary in North America and the Bombardier Flexjet block-charter programmes in Europe and Asia. Around 220 Learjet 45s were in service worldwide when the AD was issued.

Source: Flight International