As HAV's giant Airlander prepares for its UK maiden flight, TIM ROBINSON assesses whether airships are really back from the dead.

Ready for flight. HAV's Airlander 10, now fully assembled, in the giant hangar at Cardington in Befordshire.

Sometime in the very near future the skies over Bedfordshire, UK, will be darkened by the huge and unmistakable shape of Hybrid Air Vehicles Airlander 10, the first of a new generation of lighter-than-air vehicles, as it takes its first flight in the UK.

Revealed fully assembled, with fins, cockpit module and engines fitted, to the world’s media on 21 March in Cardington, it is difficult not to be awed by the sheer size and scale of the 92m long Airlander as it sits in its giant hangar – more like a grounded spaceship than a human-built flying machine. Powered by four 325hp diesel engines which can vector to provide vertical take-off or landing, the Airlander 10 can carry a payload of up to 10 tonnes/48 passengers (about the same as an Airbus C295 transport) or stay aloft for up to five days, while cruising at 80kt. Even more incredibly, it can, say HAV, go half way around the world on a full tank of fuel.

A previous UK airship venture - Airship Industries Skyship blimps of the 1980s seen over London. (RAeS/NAL)

Cardington itself, of course, is the historic home of Britain’s airship industry – dating back to 1915. But can Airlander rise again where previously the R100 and R101 and more recent comebacks by Aerospace Developments and Airship Industries failed? What makes HAV so confident that this time, airships are back for good?

Not your great-grandfathers’ Zeppelin

New superstrong, yet lightweight material gives the hull its aerodynamic shape and contributes 40% of lift. 

“It’s new material science” that now makes a non-rigid hybrid airship possible, says HAV CEO Stephen McGlennan. With Airlander, up to 40% of the lift is provided by the hull’s aerodynamic shape – effectively turning it into a massive wing. The skin of the hull itself provided by spacesuit maker ILC Dover, is made of extremely thin, but tough and very lightweight layers of materials. A Vectran weave on the inside gives strength, while a Mylar layer makes a gas-tight layer. Finally, a Tedlar layer on the outside provides protection from the elements. This means that, unlike WW1 Zeppelins, where cow intestines were used to contain the hydrogen, Airlander is expected to leak helium at a very marginal rate – only requiring occasional top-ups.

Incidentally, industrial gases supplier BOC, which provides the million cubic feet of helium stresses that a perceived scarcity of helium will not be problem for airships – though finite, the world’s supply of helium will double in 2020-21 thanks to new fields in Russia coming online. Previous concerns of helium shortages, BOC say were down to management of the supply, rather than shortages of the actual gas.

This combination of aerodynamic lift (validated by CFD modelling studies) and helium buoyancy is why, say HAV, the ‘hybrid’ airship represents a new class of flying vehicle and should not be confused with previous Zeppelins or blimps.


HAV's Airlander flight simulator uses a custom flight model incorporating the craft's bouyancy.

It is not just the hull where 21st century technology is involved in updating one of the earliest forms of aviation. The flight control system, rather than fly-by-wire (as in military jets and modern airliners) is fly-by-light – using around 7km of optical fibres to connect the cockpit with engines and control surfaces. This has the benefit of being extremely lightweight compared to copper control cables.

Interestingly, too, is despite Airlander's US military connections (and ILC Dover providing the hull material) is that HAV's hi-tech supply chain is 80% UK-based. For example, the advanced lightweight composite used on Airlander comes from Forward Composites (formerly CTS/Lola Composites) based in Cambridgeshire. In 2015, in its previous guise as CTS, Forward won a RAeS Silver Medal for its work on the Beagle 2 space probe. In a time when Whitehall is particularly keen to push British manufacturing, innovation and UK exports, HAV's Airlander is particularly well suited for this.

Outside validation

Competition from Lockheed Martin's own cargo airship project has boosted HAV's credibility in developing hybrid technology. (Lockheed Martin)

As a previous Insight blog has revealed, it is not just HAV that is interested in this technology and there are a number of ‘next-generation’ lighter-than-air concepts around the globe based on rigid, semi-rigid and non-rigid airship designs. US defence giant Lockheed Martin is perhaps the Goliath to HAV's David and is itself investing in a commercial hybrid airship – with a plan to fly its vehicle in 2017. HAV chief McGlennan says LM’s pursuit of this technology “has been hugely helpful to us for validating the concept” – and convincing the world that it is not just a flight of fancy from a small UK company.

Interestingly, Google, too, was reported to be interested in developing cargo airships as part of its ‘moonshots’ innovation lab concept that could potentially change the planet, but dropped the idea as it reasoned $200m for a demonstrator was too expensive to find out whether this was, indeed, a game-changer.

Bargain of the century?

The US Army's LEMV flew in the US in 2012 but was cancelled in 2013. (HAV)

Yet, in a fortuitous turn of events, HAV now finds itself in possession of this potential game-changing aerospace technology, with $154m of development costs already met by the US Pentagon, when the US Army’s LEMV long-endurance spy airship was axed in February 2013. For LEMV, designed as optionally-manned surveillance platform able to stay aloft for 21 days, HAV provided the air vehicle, and Northrop Grumman was the prime contractor. Despite a successful first flight in 2012 in New Jersey, the LEMV was never deployed to Afghanistan.



In 2013, aided by the UK Government, HAV bought back its LEMV prototype for a knock-down price of $301,000 and has been now spending approximately $12m readying it for a return to flight. For a major aerospace project, this is unbelievably cheap. Re-engining the A320, it is estimated, cost Airbus over $1bn – while the US Army’s JLENS tethered aerostat has cost a staggering $2.7bn. HAV’s investors and backers then, could eventually good returns from what today is a fairly low-cost, yet potentially revolutionary technology.



Civil roles....

Ecofriendly aerial tourism could be one niche for Airlander (HAV)

So what sort of roles could it perform? While operating costs are extremely low, don’t expect the Airlander 10 (or the larger Airlander 50) to replace 300-seat airliners on transatlantic flights. However, there could be useful niches in aerial sightseeing where this slow, stable flying vehicle could find a market. Indeed, while the Airlander is currently powered by four diesels, HAV say it is already looking at swapping the forward engines for electric powered thrusters. The idea here, says the company, would be to use the rear diesels for take-off, then switch to the forward electric engines for cruise. For zero-emission, silent aerial cruises over natural wonders like the Grand Canyon or African Savannah this could be a green way of seeing the planet – and spark off a new environmentally-friendly aerial tourist industry. Further in the future, it is not too difficult to imagine how solar-panels on the top surface, powering electric motors, could make Airlander even more green.



Another civil use could be for resupply and logistics (for example in Alaska or Siberia) for mining or logging industries in remote areas where roads and infrastructure is unavailable.



Airlander forward engines. HAV is already thinking of swapping these for electric motors. 

Humanitarian aid would be another obvious mission – and would allow large amounts of food, water, shelters or medical aid to be delivered to the scene of the disaster – instead of being transferred from larger transport aircraft, to helicopters. Aerial filming or research could be other roles, or even advertising – already performed by blimps.

And, while the air cargo industry is currently in the doldrums, hybrid airships may offer new opportunities to global freight specialists as a mode of transport that is faster than ships, but cheaper than aircraft. Indeed, it may very well be that hybrid airships, rather than competing with air freight, could make inroads into the surface shipping market. Is there, for example, enough classes of goods that fall between fast/expensive and slow/cheap? Far-fetched? Possibly, but in a world where what started as an online book store in 1994 is now developing its own drones to deliver packages directly to consumers’ doors – cargo airships no longer seem so fantastical.

And military missions...?

Could a hybrid airship as an ISR overwatch platform and F-35 network communications node?

Interestingly, a military role for Airlander, too, may return. While some may scoff at an airship being used in modern warfare – it turns out that it is not such an easy target. Previous trials and testing on earlier airships revealed that it would simply soak up small arms fire, while it is unclear whether the low thermal signature of its shrouded ducted fans would be enough to attract a heat-seeking missile. Even its radar signature, (thanks to the effectively transparent to radar hull) is only believed to be the size of Cessna.

While it might be used in long-duration surveillance, ISR overwatch or border patrol, others have suggested it could also be used as an airborne communications node or relay station. It is noteworthy, for example, that a recent RUSI paper on the F-35 suggested that the UK should look at an ‘airborne node’ requirement to transfer data from 5th generation fighters to other platforms. Could Airlander be a possible solution?

Military transport could also be another mission – and the Airlander 50s payload of 50 tonne (more than an A400M) and a VTOL capability might well prove attractive in the defence market – offering a unique platform for strategic airlift.

HAV say that at Cardington it could assemble up to 12 Airlanders a year. It is worth noting that even if successful, it is still likely be a niche product with low production numbers compared to civil airliners (although one forecast identifies a potential market for 600 hybrid air vehicles over the next 20 years). Do not expect 100s of orders placed at Farnborough Air Show or for airships to be flying you on holiday to Ibiza any time soon.

Remaining challenges

Airlander flight deck and payload module. Note weather radar. 

Yet there some obstacles still remain. Ground handling of airships can be more complex due to the requirement to moor them into the wind and the sheer size of the vehicle. The Airlander 10, for example, while it has inflatable amphibious 'skids' to land on a wide variety of surfaces, will still need a short mast to be secured. The follow-up Airlander 50 (able to carry up to 50tonnes), however, will have a hovercraft-style landing system to manoeuvre and to ‘suck’ the airship down to the ground to on/off load cargo and passengers. This system will thus vastly simplify handling.

Weather too, is more of a consideration for an airship pilot at 80kts than a jet airliner captain, who can use speed to punch through or climb higher to go over bad weather. However, HAV say that this would be no different to how an ocean-going yacht crew would plot a course to avoid hurricanes. Perhaps the biggest challenge, then, is one of public perception or the ‘giggle factor’. Aviation, despite its reputation for high technology, can be extremely conservative in some respects. Who, in 2016, will be the first company to go ahead, take the plunge and recommend to their board they buy an airship? For this reason, the upcoming customer trials, demonstrations and proving flights will be especially important.

Next steps to rebirth

Could this appear at Farnborough in July? (HAV)

With a first flight under their belt, HAV say that the Airlander will then need some 200hrs of flight testing. After that, customer demonstrations and trials can begin in earnest. CEO McGlennan is positive about the potential customers: “there is huge interest” he says, with about a 40%/60% spilt between potential military and civil customers. HAV is working with UK defence sensor experts Selex ES on a potential customer demonstration for UK MoD. There is also the tantalising possibility of an appearance by Airlander at Farnborough Air Show in July. Asked by AEROSPACE about this, McGlennan hinted: “We hope so, if we can do it safely”. While the prospect of a mammoth 92m-long British-designed and built airship stealing the show at Farnborough is undeniably exciting – it is also worth noting that two years ago saw the F-35’s appearance seemingly jinxed by pre-show hype. It would therefore be wise to set expectations accordingly.

Summary

Not so funny now? Airlander is now attracting serious interest from ariound the globe.  

So after earlier failed attempts to fully reboot the airship such as Cargolifter, DARPA’s Walrus, USAF’s Blue Devil, and US Navy’s MZ-3A can HAV bring airships back from the dead? (Zeppelin NT meanwhile, has only built five airships). While it is difficult at the moment to judge whether HAV will eventually succeed, it is now the closest anyone has got in recent history to a practical hybrid airship, ready to be productionised.

Just four or five Airlander orders now stand between HAV and a viable commercial project and the ‘giggle factor’ (apart from predictable Kim Kardashian references) is rapidly disappearing. Serious customer interest is now rising as word gets out and first flight draws close. When that huge shape flies over Cardington in the very near future, the 21st century rebirth of airships may cease to be the butt of aviation jokes.

 

 


24 March