The German Air Force (Luftwaffe) has declined to accept delivery of two Airbus A400M transport aircraft over technical issues identified during routine inspections.

Recurring technical problems were cited as the primary reason for the decision to not take the delivery.

The military branch found problems with the mounting nuts used on the propellers of the aircraft.

During inspections of the A400M already in flight, it was found that some of the nuts do not have the required tightening torque.

The airforce stated that if the problem is not rectified, it could cause structural damage to ‘the propeller and shaft of the propeller gearbox’.

It ordered further inspections to test fastening nuts. The service will also perform inspections to check engine mounts, engine flaps, combustion chambers, and test for detection of cracks on other parts.

Luftwaffe noted that the additional inspections have affected the readiness of the A400M fleet.

The A400M has been used by the German Military in more than 1,700 missions.

The aircraft support the airforce’s requirement to transport forces and material, as well as perform air-to-air refuelling and humanitarian aid missions.

Airbus has so far delivered 31 out of the 53 aircraft ordered by the German Armed Forces.

In a press statement, Luftwaffe said: “The total technical deficiencies and the finding that the two machines currently being delivered additionally do not possess the contractually guaranteed properties lead to the current non-acceptance of these aircraft by the Bundeswehr.”

In response, Airbus issued a statement saying the problems raised by the airforce were not safety-critical.

The company was quoted by Reuters as saying: “We are aware of findings related to dowel bolts / propeller interface in some of our customer aircraft. This is not safety-critical and our customers continue to accept and operate their aircraft.”

The A400M aircraft was commissioned in May 2003 to meet the airlift needs of European countries, including the UK, France, Belgium, Germany, Spain, Luxembourg and Turkey. Malaysia joined the programme in 2005.