In-flight refuelling operations are among the most demanding missions. Both the tanker and receiver pilots need to operate in close formation, flying aircraft with different flight envelopes and ranging speeds, in day-and-night and all weather conditions, and above the battlefield... There are many factors that are unpredictable and could put the missions at risk.

The Airbus A330MRTT has a solid track record providing safe operational services to its customer base and other allies like the USAF. The Airbus aircraft gained its reputation as a tanker after seeing action in the Middle East supporting coalition war fighters during Operation Shader and Okra against Daesh, with interoperability, mission success and availability rates as a highlight of its performance.

But for Airbus' engineers, the road to success does not end here. They envisaged a new chapter where, under the name of SMART MRTT, the multirole tanker gained a new set of game-changing capabilities including enhanced maintenance solutions and the ability to carry out fully automated aerial refuelling operations.

The automatic refuelling system was called A3R and the idea behind it was clear: reduce air refuelling operator (ARO) workload, improve safety and optimise the rate of air-to-air refuelling (AAR) transfer in operational conditions to maximise aerial superiority. Everything at the 'simple' push of a bottom.

Revealed to the public in 2018, the A3R has met every milestone, including several aeronautic 'world firsts' such as the first automated contacts. In a joint operation with the Royal Australian Air Force (RAAF) an Airbus' A310 company development tanker performed seven automatic contacts with a RAAF KC-30A Multi Role Tanker Transport. More recently, in 2020, Airbus announced the first ever fully automatic refuelling operation with a boom system. The flight test campaign involved an Airbus A310 tanker testbed aircraft with an F-16 fighter aircraft of the Portuguese Air Force acting as a receiver.

2020 also saw the announcement by Airbus to collaborate with the Republic of Singapore Air Force (RSAF) to develop the A330 SMART MRTT programme. Singapore became a key partner for the new automated aerial refuelling capabilities and under the agreement, an RSAF A330 MRTT took part in the development, flight test campaign and final certification programme.

Successful trials in Singapore

Now the A3R has taken another important leap towards certification with the completion of the development phase after a successful flight test campaign.

The trials, performed with the RSAF and Singapore's Defence Science and Technology Agency (DSTA), took place in Singapore in early 2021. It marked participation of an A3R-equipped RSAF A330 MRTT acting as tanker and several receivers from the RSAF, including another A330 MRTT and fighter aircraft like the F-16 and F-15SG.

During the trial, a total of 88 fully automated dry and wet contacts and transfers of nearly 30 tonnes of fuel were successfully executed, including the first fully automated operations with another A330 MRTT and RSAF F-16D/F-16D+ receivers.

All tests required for A3R Data Gathering with the F-15SG, including operational flights to demonstrate the A3R performances in a mission representative scenario were also completed.

Luis Miguel Hernandez, Airbus SMART MRTT Manager, said: 'We had the opportunity to test our system with different receiver types ensuring the right fit of our systems, while gathering extensive data key to completing the A3R development. The team were able to test the limits of the system successfully, verifying its robustness and ability to automatically track receivers with varying configurations'.

Key to the mission success was the excellent cooperation with the RSAF and DSTA. 'We have built an extraordinary relationship based on mutual trust. Teams from all sides worked as a single unit during the test campaign and it is always a pleasure to fly with such a professional crew. They are the first partner nation involved in the development of the SMART MRTT, and we are honoured to have them on board', added Hernandez.

Trapped with Filomena

The latest set of tests were not 'challenge-free'. In addition to the complex technical organisation inherent to a development of this magnitude and the omnipresent COVID context, the teams were faced with yet another challenge: storm 'Filomena', an unexpected and historic snow storm that blasted Madrid, Airbus Getafe facilities included, days before the departure of the team to Singapore.

'With tonnes of snow blocking every inch of Madrid forcing the closure of Airbus facilities, a tremendous collective effort, racing against the clock was required to ensure the teams were able to take off and reach Singapore on time to start the campaign', said Luis Miguel Hernandez.

Road to certification

After the successful campaign and with having gathered all critical data, the teams are now gearing up for the next phase, including readiness of the final A3R version and preparation for a very demanding roadmap that will lead to certification by the end of 2021.