Tanker Of Choice

“We believe very much in systems interconnection, we have the skills to do that, and that’s where we are going to be focusing. ” That aligns with the concept the RAAF dubs the ‘smart tanker’ – using the KC-30 as the ‘node’ in the networked battlespace.

But it also illustrates the growing maturity of the MRTT platform, with 28 aircraft already delivered to four countries out of 49 on firm order, and the aircraft’s development problems, particularly with the Aerial Refuelling Boom System, now largely behind it.

The RAAF was in fact the launch customer for the MRTT in 2005. Since then Australia has taken delivery of an initial five KC-30s and ordered an additional two (to be converted from ex Qantas A330-200 airliners), all 14 for the UK’s RAF will have been delivered by the time these words are written, six are in service with the Royal Saudi Air Force and three are with the United Arab Emirates Air Force. That fleet has already flown over 85,000 flight hours, Airbus says, should pass the 100,000 flight hour milestone this year, and last year averaged 1,200 flight hours per aircraft.

In part that is due to the high rate of effort of Australia’s KC-30s – in 2015- 16 the RAAF’s KC-30s flew 6,000 flight hours. Those numbers are bolstered by the deployment of a single aircraft to the Middle East in support of Operation Okra. The RAAF has had one KC-30 deployed to the UAE in support of RAAF and coalition fighter operations over Iraq and more recently Syria since September 2014. In that time, through to May, the KC-30 has flown over 5,000 flight hours, averaging 250 a month, and over 631 sorties at an average of over 30 a month.

And on April 27 the RAAF marked the milestone of 50 million pounds of fuel offloaded in support of coalition forces.

“The ATG630 Air Mobility Element has built the KC-30A’s reputation as the ‘tanker of choice’ amongst Coalition air forces in the Middle East,” Commander of ATG630, Air Commodore Antony Martin said in a statement marking the 50 million pound offload milestone.

“We normally take off with more than 100 tonnes of fuel on board, and can give away more than half of that if we’re flying a sortie over Iraq,” the (unnamed) Air Mobility Element’s Detachment Commander said in the statement.

“Quite often, the Air Mobility Element will fly back-to-back KC-30A missions, returning to our main air operating base in the Middle East to change crew and refuel before launching again. ” Another illustration of the MRTT’s maturity is the number of aircraft types it has been cleared to refuel, from the RAAF’s classic and Super Hornets and Wedgetails to RAF and Saudi Eurofighters, Saudi F-15s, UAE F-16s, French Rafales and US Marine Corps AV-8B Harriers.

And this year both the RAAF and RAF have conducted refuelling trials with the F-35 JSF, with the F-35A and B models respectively, and the RAAF has conducted trials with the C-17 as well.

“But the aircraft is connected in the battlefield, it is not just a gas truck, it’s not just a gas pump for the receiver, it’s much more than that,” Airbus DS’s head of marketing for MRTT and other Airbus derivatives, Jeronimo Amador told media in late June.

“All current customers agree on the extra capacity of the A330 MRTT to do more. So what we are doing with them and . . . with key partners and suppliers is to expand the use of the MRTT. ” Amador, speaking at Airbus DS’s annual Trade Media Briefing (TMB), detailed developments Airbus is working on to improve the aircraft’s capabilities, a number of which Australia has shown interest in.

One of those is a datalink relay technology Airbus is developing for the MRTT, which would either use IP Satcom or UHF Demand Assigned Multiple Access (DAMA) radio technology to relay Link 16 targeting information.

“The Australians … are well interested in this application,” Airbus DS head of engineering Miguel Angel Moreno told the TMB in a separate briefing.

We normally take off with more than 100 tonnes of fuel on board.

Airbus has already performed Link 16 data exchanges in a lab environment using a simulated satellite network and a UAV ground station.

“We are very adaptable to customer requirements,” Amador said, from “basic” requirements like internet connectivity and email access “up to full military capability integrated through wideband satcom. ” Intriguingly, Amador also offered that: “We are also considering new intelligence, surveillance and reconnaissance capabilities to be added into the A330 MRTT. So we are analysing for example COMINT equipment,” he noted, without providing further details.

Australia is also watching closely the development of the automatic refuelling technology, Moreno told the TMB.

“A lot of Air Forces are interested, the Australians are much more interested in this capability and other nations also are waiting for this to see … the results,” Moreno said.

“But the Australians already are asking for this capability. ” Using the MRTT’s cameras, image processing software and the aircraft’s fly-by-wire Aerial Refuelling Boom System, the automatic refuelling technology is designed to reduce risk and to increase tanker productivity by increasing the number of refuellings possible per mission.

“The process we follow is that the boomer [boom operator] flies it manually until a certain position, and then in a certain moment deactivates the automatic [mode]. Then the operator can choose if he wants to continue manually or pass to automatic mode,” Moreno explained.

“The contact is a hands free operation. ” So far Airbus has completed an inflight operational evaluation of automatic refuelling without making contact with an F-16 receiver aircraft, while a flight test campaign making contacts with a receiver aircraft is planned for the end of 2016.

Adding the capability to the MRTT requires only software changes, but a future fully autonomous refuelling capability would require more extensive hardware changes and certification.

“The moment the boomer touches the stick, the automatic mode disappears. The boomer is in the loop, the next step for us is to remove the boomer,” Moreno said.

“In order to do it fully automatic without the boomer in the loop, then the architecture has to be revised and the safety case has to be revised. Today with the boomer … in case something happens he can take control. ” Another software-driven enhancement for the boom is “augmented reality” training for the boom operator, Amador explained.

“This is the combination of flying a real aircraft with a real boom but the receiver [aircraft] is not real, it is an augment reality injected into the [screen] of the boomer. ” The augment reality capability has already been tested on the company’s A310 tanker testbed, Airbus says, and it allows the boom operator to make refuelling ‘contacts’ with synthetic receiver aircraft, with the boom’s handling characteristics “fully representative” of a real refuelling operation.

“So that allows a next step between the simulator and the real training for the boomer operators,” says Amador.

Other developments are based around improving the situational awareness of receiver aircraft pilots, including hose length indication lights and visual aids comprising LED ‘traffic lights’ and hose markings to inform the receiver aircraft of its position within the refuelling envelope, particularly in low visibility and night conditions.

“We expect this to provide a significant increase in the situational awareness of the receiver pilots on the approach or separation. ” Then there are improvements to the A330 airframe itself, which has received modest upgrades since the first RAAF aircraft flew in 2007. Most significant of those is an optional increase in maximum takeoff weight to 238 tonnes.

“That means, for instance, on a typical transport mission of 6,000nm we can increase the payload up to 20 per cent,” Amador says.

Other minor aerodynamic changes to the A330 including shortened flap track fairings and reshaping of the inner slats has yielded up to one per cent improvement in fuel burn.

The A330 has also received structural modifications since the RAAF’s aircraft were built, including mods to the wingbox and main landing gear.

Further MRTT improvements in development include a CAT III autoland capability, IFF Mode S and ADS-B out, an electronic flightbag, a new boom control stick, and new “self-protection options”. Australian KC-30s are fitted with the Northrop Grumman Directional Infrared Countermeasures (DIRCM) missile warning system and electronic warfare self-protection (EWSP) suite. Amador said Airbus is “analysing alternatives for those customers that may not have access to that equipment due to export licences. ” Taken together, the new upgrades represent a new baseline standard for the MRTT, but the intent is for all the upgrades to be retrofitable to existing aircraft as well.

“That’s our target, for all of them to be retrofitable and to have a customer base as wide as possible,” Amador said.

Even the increased max takeoff weight is retrofitable, as it involved a change to the aircraft’s certified max takeoff weight rather than any physical changes to the airframe.

However, there is no plan among the existing MRTT user group – which meets formally once a year – to agree on and maintain a common configuration of aircraft.

“Trying to share future development costs, trying to maximise the future evolution of the fleet – we and the customers agree on the fact that the more commonality the better for the future of the tanker fleet. But there is no mandatory [requirement for the] installation of any upgrades, we will keep the flexibility for every customer to decide,” Amador explained.

On the training and support side Airbus is planning to invite MRTT customers to take part in a “virtual joint fleet”, a common spare parts pooling arrangement, details of which are still being developed.

We and the customers agree on the fact that the more commonality the better.

More mature is Airbus DS’s plan to acquire a full-flight simulator (FFS) from Indra to support the training of A330 MRTT crews.

“We have decided to invest into an A330 MRTT full-flight simulator, which we’ve not had so far, which has meant a lot of the training for this aircraft needed to be done on the aircraft,” Stephan Miegel, Airbus DS head of military aircraft services, told the TMB.

“And as you can imagine on-aircraft [training] is of course limited in the amount of problems you can exercise or the amount of difficulties that you want to train for. ” The new Level D full-flight simulator will be installed at the Airbus DS International Training Centre in Seville, Spain.

In addition to providing flight training, the simulator, which is due to enter service in the second quarter of 2018, will permit the training of pilots in hose-and-drogue refuelling operations, and to act as a receiver from other tankers.

“It offers the opportunity of greatly reducing the amount of aircraft flight hours required to train air-to-air refuelling crews.

“We are also examining the most cost-effective way to link the FFS to a part task trainer that would allow training of complete crews on [air-to-air refuelling] using the refuelling boom system, in addition to hose-and-drogue,” said Miegel.

A day in the life

The KC-30A’s capability was demonstrated during a routine Operation Okra sortie on April 30, as this Department of Defence account shows: The sortie began by refuelling a pair of United States Navy Super Hornets flying from an aircraft carrier in the Persian Gulf.

The process begins with a hose-and-drogue being unreeled from pods beneath each wing of the KC-30A, trailing a pair of baskets for the Super Hornets to intercept with a refuelling probe.

The air refuelling operator (ARO) on the sortie, Flight Sergeant Colin Weekes, said the KC-30A was a popular tanker for the Navy pilots.

“The US Navy doesn’t have its own tankers flying over Iraq and Syria – they’re relying on the US Air Force and Coalition Tankers in the area,” FSGT Weekes said.

“Our tanker has ‘soft baskets’, which shouldn’t damage their aircraft if they do make contact with it during the refuelling.

“We also have longer hoses too that allow them to keep space and see what’s going on around them. ” The KC-30A’s next receiver was a RAAF E-7A Wedgetail, rendezvousing over Mount Sinjar in northwestern Iraq.

Refuelling the E-7A requires the use of the KC- 30A’s Advanced Refuelling Boom System, which is guided by fly-by-wire controls by the ARO.

The first contact over Iraq between a KC-30A and E-7A occurred in October 2015, and now typically occurs at least once a week.

Watching through 3D cameras, the ARO uses fly-by-wire controls to move the boom into a ‘pre-contact’ position.

The ARO then extends a probe in the boom into a refuelling receptacle on the receiver aircraft.

During the contact, the E-7A will take on up to 15 tonnes of fuel, a process that takes up to 12 minutes and requires both aircraft to fly a racetrack pattern together in the skies of Iraq.

The ARO’s screen also displays the planned amount of fuel to offload, the rate of transfer, and the total transferred.

“Once the fuel starts transferring, it’ll keep going until a number of things stop it – either I stop it, the receiver pilot stops it, or they reach their offload limit,” the ARO said.

Following on from the E-7A, the KC-30A crew can use the Link 16 datalink to see that a United States Marine Corps EA-6B is waiting to be refuelled.

“Link 16 allows us to have greater situational awareness of where everybody is in the airspace, and their different altitudes and different ranges,” FSGT Weekes said.

“If I select an aircraft and tag it as ‘cooperative’, I can also work out how much fuel they’ve got on board. ” Before the KC-30A returns home, it reunites with the two US Navy Super Hornets to provide them with enough fuel to remain over Iraq or Syria.

Being able to refuel two aircraft simultaneously is another reason the KC-30A is popular amongst Coalition air forces.

“When receivers see an Australian tanker with two hoses, they know they can both get refuelled quick, and get back onto the job that they’re there to do. ”