Flight test ‘lite’: Qinetiq’s VAAC Harrier highlights capabilities of Lockheed Martin’s STOVL Joint Strike Fighter

It’s hard to believe the amount of time that has passed since Lockheed Martin won the USA’s Joint Strike Fighter (JSF) contest, but October will see the fifth anniversary of the company’s victory over rival manufacturer Boeing in the most spectacular of “winner takes all” contests. This October will be another massive month for the US-led project, as Lockheed could conduct the first system development and demonstration phase flight of an F-35 – the next-generation combat aircraft which has now been dubbed the ‘Lightning II’.

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Like one of my current favourite aircraft – the US Air Force’s Fairchild A-10 Thunderbolt II, or ‘Warthog’, the JSF poses a major problem to the enthusiastic, but thoroughly untrained aviator such as me: it only has one seat. This means that although we are probably at least six years away from the type’s entry into service with current potential buyers Australia, Canada, Denmark, Israel, Italy, the Netherlands, Norway, Singapore, Turkey, the UK and the USA I’m already depressed by the knowledge that I will never get the chance to fly in one.

Thankfully, technology is a wonderful thing and I have now had the good fortune to twice have a go at flying the JSF in the synthetic domain. The first chance came about two years ago when I briefly flew a representative simulator for the JSF as part of a military demonstration here in London, but it wasn’t until just before last month’s Farnborough air show that I got a really good taste of what the new aircraft will be like to operate in one of its most challenging flight scenarios: vertical landing.

The US Marine Corps and the UK Royal Air Force and Navy will be the launch users for the short take-off and vertical landing (STOVL) F-35B, with the type to replace their Boeing AV-8B Harrier II and BAE Systems Harrier GR9/9A ground-attack aircraft from around 2012. You’re 10 times more likely to have an accident flying a Harrier than another fast jet type, says Justin Paines, a development test pilot for UK research and technology company Qinetiq who flew 11 sorties on Lockheed’s X-35 demonstrators before leaving the RAF. And that was before he saw me trying to fly a Harrier simulator at the company’s Bedford site…

I had my first flight in a Harrier earlier this year with the RAF’s 20 Sqn operational conversion unit, and now know it was a good job that I didn’t realise how unruly the aircraft is in the hover before I had a go at the controls. I’m ashamed to say it, but flying the simulator for Qinetiq’s unique VAAC Harrier – the oldest two-seat example of the type flying in the world, with more than 30 years of research work now behind it – was a disastrous failure for me in conventional mode. Within seconds of taking control of the aircraft in the hover it was spiraling wildly on its axis and pitching about like a bucking bronco. And then I crashed it. Twice.

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But my visit to Bedford wasn’t intended solely to dent my confidence. Qinetiq had invited me to the site to fly the device under the supervision of Paines and two of the UK Ministry of Defence’s test pilots from Boscombe Down in Wiltshire to show me how much better things will be in the F-35B. Qinetiq has since 1999 used its lone VAAC airframe to assess a variety of flight control laws intended to make a JSF pilot’s life a whole lot easier and is now involved in a flight test campaign to fine-tune the likely final configuration. You might have seen a news report yesterday by ITV science editor Lawrence McGinty, who was also receiving instruction at Bedford but – unlike me – was lucky enough to go on to successfully fly and land the real VAAC Harrier at Boscombe Down.

While it is without question one of the greatest engineering marvels of the first century of manned flight, the Harrier is a confusing beast to fly, with more controls to take care of than the pilot has hands. With the F-35B, however, that problem will be no more, and I was assured that after no more than a quick briefing I would be able to fly and land the VAAC Harrier, this time using its so-called unified control laws. After one dummy run with a test pilot looking over my shoulder I locked myself into the domed motion simulator, strapped myself in to the unique Harrier cockpit and prepared to redeem myself in front of the professionals.

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Here’s the really good news for anyone reading this who might be pondering embarking on a career as a fighter pilot within the next decade or so: it really will be easy to fly a JSF in the STOVL configuration. Forget the current requirement to control the Harrier’s attitude with the joystick, its forward speed with the throttle and (and here’s the difficult bit) its nozzle control lever to stop it from falling out of the sky. In the F-35B the left-hand will control the throttle inceptor: push forward and you accelerate forwards, pull back and you decelerate and eventually go backwards – and the bigger the input the greater the response. In the hover the right-hand side-stick will be used to control everything else: push left or right and the aircraft will jink to the left or right, push forwards and it will descend, pull back and it will climb. On my two attempts to enter the airfield circuit and land on a pad using visual markers to line the aircraft up I succeeded in getting the VAAC down safely, albeit at a snail’s pace, which did wonders for my dented confidence.

If the modified Harrier’s performance is anything to go by, the stability offered by the F-35B’s liftfan and roll posts will be truly spectacular, with only slight inputs required to manoeuvre it around an airfield or onto the deck of an aircraft carrier or assault ship. And Qinetiq has already successfully demonstrated the VAAC Harrier’s ability to automatically return to and land aboard a rolling and pitching aircraft carrier with centimetric accuracy, meaning that the F-35B’s safety record should be remarkably better than the STOVL platforms it will replace.

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It’s not just in the hover that the F-35B will be different to fly. I’ve always found it difficult to maintain the determined height during a turn, but during my simulator ride I found that on each turn I was gaining a considerable amount of height, as my automatic reaction – to pull back on the stick slightly to maintain my altitude – was not necessary in the new generation aircraft. The flight control system knows how much throttle the pilot has requested and will make adjustments during the turn to make his or her life that little bit simpler and free up valuable time for system management tasks.

My initial attempts to hover the VAAC Harrier had been so spectacularly bad in conventional flight mode that my test pilot guide later quipped in an e-mail: “I’m very confident that you have got a good understanding of the differences of control between the old Harrier and where we are going with the JSF control laws!!”

But if all this technology is going to make it so spectacularly easy for a pilot to fly the STOVL variant JSF, what will the next generation of pilots for these aircraft have to boast about over their peers on conventional platforms like the Eurofighter Typhoon? “That’s easy,” says one test pilot: “we’ll still be able to hover!”

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