Airbus Military has identified the cause of an in-flight refuelling boom detachment that affected an A330 multirole tanker transport early last month, and says the incident was the result of a unique set of test circumstances.
The EADS-designed boom structure detached from the aircraft during a customer pre-acceptance flight on 10 September, before falling in a remote part of Spain from an altitude of 27,000ft (8,230m). No-one was injured in the incident, and the tanker - one of three destined for delivery to the United Arab Emirates - landed safely at Airbus Military's Getafe site near Madrid.
Airbus Military says a unique addition to the boom developed for the customer was being tested at the time of the incident. A back-up boom hoist intended to allow the structure to be retracted in the event of a failure to its primary system was being used, but its effects were unexpectedly countered by the main system until a failure and separation occurred. The set of circumstances being tested during the sortie could not have happened under normal operating conditions, the company notes, and procedures have been drawn up to prevent a repeat.
Spain's INTA airworthiness authority is expected to soon lift a set of precautionary operating restrictions that was issued to other operators of the A330 boom system as a result of the mishap. These include Australia (file image of Royal Australian Air Force KC-30 above) and Saudi Arabia, neither of which selected a back-up hoist capability for their aircraft.
Meanwhile, discussions continue towards the agreement of a delivery schedule for the UAE's new tanker aircraft. The Gulf state had been due to accept its first two modified A330s in September and December 2012, according to a schedule released by Airbus Military during May.
Initial operational test and evaluation activities conducted with its first aircraft earlier this year included successful in-country boom contacts made with Lockheed Martin F-16 combat aircraft (below) and hose and drogue refuelling work with Dassault Mirage 2000 fighters.