Tiltrotor poised to enter final qualifying event before going into full-rate production
With preliminary flight tests all but complete, pressure on the Bell Boeing design and production teams has shifted to completing the last major tasks to clear the US Marine Corps MV-22 programme to enter a critical operational evaluation (Opeval) next month.
The last two MV-22As have yet to be delivered to VMMT-22, the USMC unit charged with conducting the MV-22's final qualifying event before entering full-rate production in 2005.
The five-month Opeval phase is intended to review the operational suitability and effectiveness of the A-model. VMMT-22 has 11 MV-22As, of which five were retrofitted to the A-model standard and cannot be flown as part of the evaluation, says Bell. The unit has a requirement for two more aircraft produced as A-models. Opeval requires a minimum of eight MV-22s to be available for test flights.
Bell says both of the last two MV-22As to be delivered to VMMT-22 have left final assembly and are undergoing checkout flights at Bell's site in Amarillo, Texas. The first aircraft is on track for delivery this month and the second aircraft is due for delivery in January.
Opeval cannot begin until all eight aircraft are stationed with VMMT-22 at New River, North Carolina.
Another pre-Opeval task for Bell Boeing is to complete the redesign and installation of a new nacelle blower, a component discovered in June to be prone to failure early in its operational life. An MV-22 was forced to make an emergency landing after the part blew out in flight. The redesign includes a strengthened shielding panel, ball bearings and sealant.
Completing Opeval early next year would cap a four-year effort to re-establish a programme that suffered two fatal crashes in 2000. The programme has used the interim period to put to rest concerns about the tiltrotor's susceptibility to vortex ring state and its shipboard compatibility, while continuing to sustain a minimum annual production rate of 11 aircraft a year.
But Bell Helicopter is sufficiently confident in the MV-22A's record heading into Opeval that it is starting to relocate business and administrative staff from Fort Worth, Texas, to the final assembly plant in Amarillo.
Results of the operational evaluation are hoped by programme officials to clear the path for the US Department of Defense to approve full-rate production later next year.
STEPHEN TRIMBLE / WASHINGTON DC
Source: Flight International
