Airbus Defence & Space will launch flight tests in the first quarter of next year to prove the ability of its A400M tactical transport to refuel helicopters in flight.

Previous tests involving an Airbus Helicopters H225M exposed stability issues for the rotorcraft while it was operating near the Atlas, with the 90ft length of its refuelling hose also bringing it too close to the airlifter's tail.

Successful windtunnel testing has already been conducted using an updated hose design produced by Cobham. Housed within the same under-wing refuelling pod, this has an increased length of 120ft, with the use of a thinner hose to result in a slower rate of fuel flow.

The earlier problems with clearing the A400M for helicopter refuelling contributed to decisions by France and Germany to each order a small number of Lockheed Martin KC-130J tankers.

"The next test will be done with a pod and aircraft in the first quarter of 2019," says head of military aircraft Fernando Alonso. The activity will involve either an H225M or a Leonardo Helicopters AW101.

Meanwhile, Airbus and UK personnel recently advanced air-to-air refuelling trials in Spain involving a "Grizzly" test aircraft and a Royal Air Force A330 Voyager, with the Atlas receiving fuel "over a wide range of altitudes and air speeds".

Elsewhere, the A400M programme is also advancing on a permanent solution for a propeller gearbox (PGB) issue which has affected its Europrop International TP400-D6 engine.

Alonso says an interim truncated plug fix for the PGB has already been installed on all in-service aircraft, and that a permanent, "Pack 2" update developed by EPI and Avio has been certified following extended bench testing.

He says discussions are ongoing to determine when the update will be introduced to new-build aircraft, and that the interim solution is performing well in service.

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