“The Tempest mock-up and virtual concept art unveiled at Farnborough , whilst clearly very early stage ideas rather than anything approaching a prototype or tech demonstrator, do tell us a few things about British thinking in terms of a new combat air platform for the late 2030s.
Firstly, the concept still includes canted vertical fins which indicates a preference for retaining some fighter-like agility and stability in extreme flight regimes. This is in marked contrast to various concept artworks released by US OEMs in recent years which have typically eschewed vertical tail surfaces, presumably to aid all aspect signature reduction.The Hush-Kit Book of Warplanes will feature the finest cuts from Hush-Kit along with exclusive new articles, explosive photography and gorgeous bespoke illustrations. Order The Hush-Kit Book of Warplanes here
Secondly, the concepts feature a sleeker, longer fuselage than the F-35 and are clearly twin engined. This suggests an emphasis on endurance and unrefuelled range over low costs and simplicity compared to the latter and a desire to carry a larger and presumably modular payload internally. In many ways, it is remarkable the extent to which the Tempest physical and virtual mock ups unveiled mirror the design choices made by Chengdu for China’s J-20A. Large, twin engine with small canted vertical surfaces and strong F-22 Raptor influences showing around the nose and especially canopy/cockpit shaping.
Thirdly, the concept has been described as optionally manned. This suggests a British governmental approach which is not comfortable with risking calling the new combat aircraft manned or unmanned at this stage, but unfamiliar with the reasons for going in either direction. In my personal opinion, optionally manned is a terrible way of designing a new combat air system because it gives you the downsides of both without many upsides. Sure, your new combat air system could be sent in on high-threat missions without risking a pilot, but the extra electronic complexity and programming risk for developing a combat aircraft capable of operating autonomously is still required. Meanwhile, the cockpit, life support, controls and HMI still have to be included with consequent penalties over an unmanned design in weight, space, complexity and RCS reduction potential. Furthermore, aircrew still have to be trained and maintain currency on the new type, meaning one of the key cost efficiencies promised by UCAVs – not having to physically fly for currency, training in peacetime – is significantly eroded. Call me pedantic or pessimistic but for my money, optionally manned should be banned as a term in developmental projects. If you are not willing to take the risk of saying you are developing a UCAV from the outset – forget about unmanned during the development phase and concentrate on keeping costs and complexity down for your new manned fighter!
In terms of the funding announced – the UK is committing £2bn by 2025. That is a decent start and will get the UK’s foot in the door in some sort of new European combat aircraft collaborative effort (and it will of course need to be collaborative especially with France and Sweden in order to make technical and financial sense). What it will not do is fund a new combat aircraft during active testing, prototyping and development up to procurement. That will need much more than £2bn from the UK after 2025 and as such that funding will have to come from somewhere. Assuming no major uplift in defence spending – the only likely place where a new combat aircraft can be funded from within the MoD Equipment Plan in the late 2020s and 2030s is by cutting F-35 numbers from the 138 which the country still doggedly insists it will buy even though few seriously believe that by the time the last aircraft is ordered (2040ish) it would still be the best option. However, the US will react furiously to any announcement that the UK intends to curtail its F-35 buy and so for now the government is having to pretend that in combat air, as in so many areas at the moment, it can have its cake and eat it too!Re. the wing shape: I would guess that it’s a placeholder without obvious radar return issues pending proper aerodynamic testing of actual test concept mock ups rather than plastic showpieces.”