The F-35 is a Work in Progress, but it is Improving and Essential for UK Airpower

The F-35 Joint Strike Fighter remains a source of controversy and polarising performance claims. While problems with both the aircraft and the programme remain, there are no competing solutions that offer anything approaching the current or upcoming capabilities of the F-35 in contested airspace.

The F-35 as a concept has suffered since its inception from attempting to solve too many problems in a single airframe for too many potential users. In order to keep the programme alive and justify the enormous expenditure which has thus far been poured into the project, the aircraft’s proponents have oversold the F-35 as the answer to every Western combat air requirement.

It is true that the F-35, for example, will not be as effective as the A-10 Thunderbolt II at close air support using a heavy calibre cannon danger-close to troops on the ground. Equally, the F-35 cannot match a 4.5th generation fighter such as the Eurofighter Typhoon in raw performance terms, nor out-turn one in a within-visual range dogfight. However, the aircraft was never designed for either of these tasks.  

Critics and proponents of the F-35 should not lose sight of the fact that the aircraft was designed around the core task of penetrating defended airspace with an adequate internal bomb and missile load to strike critical targets, such as air-defence nodes, while maintaining a solid self-escort capability and high survivability.

The F-35’s core strengths, therefore, are its low radar cross-section and extremely capable sensor suite and information processing capabilities, which should grant any pilot the all-important situational awareness advantage over potential opponents. It already mounts a hugely capable AESA radar, 360-degree infrared and electro-optical targeting and surveillance system, passive tracking suite and electronic warfare capabilities. Furthermore, the ability of the aircraft’s systems to fuse the data from all these sensors and present a pre-sorted and interpreted single picture to the pilot places it far ahead of most mature modern jets, with improvements coming in every software block.

The F-35 is more likely to spot any operational type of enemy aircraft or air-defence radar before it itself is detected.

Critics point out that the F-35 is not invisible to radar, and metre and decimetre wavelength radars are being actively fielded and further developed by China and Russia, which can give a rough idea of where any low-observable fighter sized aircraft is. However, it is still a huge advantage to be much more difficult to detect, track and target than traditional fighters.

The United States Air Force’s superlative F-22 Raptor and B-2 Spirit heavy bomber can both be detected by various sensor types under various conditions and their missions have to be very carefully planned and tailored so that their small radar signatures can best blend into the ‘background noise’ of other aircraft, weapons effects, jamming etc.

The F-35 is no different in this regard from an F-22, except that there will be many thousands of them built and operated by a host of NATO and allied air forces as opposed to the 187 F-22s in existence and 19 B-2s.

For the UK, it is important to remember that for the majority of missions, the RAF has Typhoon which is one of the most potent multirole fighters in the world with impressive range, weapon payload and especially air defence/superiority capability. However, for high-threat environments the F-35 – whether the B variant for joint RAF/Royal Navy operations from land or the Queen Elizabeth carriers, or the A variant if the eventual buy includes it – is the only realistic option available for the UK to procure in terms of an ability to penetrate modern air defence networks.

Typhoon is many things, but it is not designed to operate against S-300/400/HQ-9 class surface-to-air missile systems, let alone future ground-based threats. The F-35 was designed to provide that capability. While the aircraft continues to experience developmental problems, such as excessive vibration in certain flight regimes, overheating issues, bugs with the ambitious helmet and no doubt others, it is worth remembering two points.

First, almost all military jets are plagued with issues during their initial service years including the Tornado F-2/3 air-defence variants, Blackburn Buccaneer and the now world-beating F-22 Raptor. What is different about the F-35 is the scale of public and media scrutiny due to the programme’s high cost and troubled history, and the complexity of the task which Lockheed Martin is trying to achieve. Second, the problems will be fixed because there is simply no alternative for the US Air Force and US Marine Corps. The UK can and should take comfort in that fact.

It is also worth looking at the Russian T-50/PAK FA fifth-generation fighter programme, which is now down to an order catalogue of a mere six aircraft, and the telling opacity surrounding avionics, build quality and combat readiness that surround the Chinese J-20A despite industrial-scale cyber espionage by Beijing in support of their efforts on that front. Building something that looks like a fifth-generation fighter is relatively easy. Building something which works like a fifth-generation fighter is supposed to is very hard, and only the US has succeeded so far.

In cost terms, the F-35 is undeniably an extremely expensive programme when viewed in its entirety. However, the fact that 15% of the value of every F-35 built throughout the life of the programme will be accrued by UK companies, coupled with the 2,500+ aircraft estimated size of the programme means that Britain stands to gain more financially from the work share secured by our quota of 138 jets than it could possibly spend on procuring those jets upfront.

As was detailed in a RUSI report in 2016, there are significant gaps in terms of RAF/RN communications infrastructure needed to ensure that the F-35 can covertly offload the situational awareness that it gathers to older platforms rather than having to transmit via Link 16 and potentially give away its position. However, this is comparatively small extra expenditure required to unlock the full potential benefits for the UK from the F-35 in terms of enhancing the combat power and survivability of legacy assets, rather than a requirement for the aircraft to work as it should in itself.

In conclusion, the F-35’s critics are right to point to many remaining problems with the jet and the huge expenditure and delays that have dogged its long development history. However, these significant remaining hurdles should not obscure the fact that the F-35 in current Block 3i software configuration is already a very potent fighter in its own right and it has more potential for growing combat capabilities in future than anything else flying. The huge number of F-35 which will be built means that acquisition and maintenance costs will continue to fall and there is huge potential for collaborative development of tactics and operational cooperation amongst a global user community. There is also, put bluntly, no other option in town for Western airpower to operate against modern evolving ground and maritime-based missile threats going forwards.  

Justin Bronk
Research Fellow for Airpower and Technology, RUSI


Professor Justin Bronk

Senior Research Fellow, Airpower & Technology

Military Sciences

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