FOAS goes ahead.

[zen]

Gratuitous quote to start.

While most of the FOAS files at Kew remain under the 30 year rule, one file I recently looked at on FCBA identified two (presumably Warton) FOAS design studies that featured in Joint Force 2000 planning around the time of the 1998 SDR and the ongoing discussions about the size and shape of the CVF and FCBA force.

P.149-25: a new design multi-role stealth interdictor
P.151-02: a non-stealth Eurofighter derivative

It was assumed either would be a post-Eurofighter collaborative venture, costing around £2 billion.
The assumed 1998 plan was 220 P.151-02 alongside 3 smaller CVF, 60 JSF for the RN and 65 Eurofighters replacing the Harrier GR.7 fleet, costing £20.1 billion.
Buying 329 P.151-02 (with no CVF programme) was estimated to cost £16.4 billion.
Or vice-versa, 3 CVF and 260 JSF with no FOAS would cost £15.7 billion.

The high number of the P.149 sub-variant indicates that a fair amount of work must have been done on stealthy designs.
Just for context, Warton's FBCA studies of circa 1994 was the P.145, with the P.145-17 being the version taken forward for comparison studies with the SSF and Eurofighter.

Assuming for the purposes of an AH Scenario(s), that MoD and Treasury agree to a national programme at least to start the ball rolling on a collaborative effort.

But it's arguable that a national programme could proceed.
This would either leave just the FAA pursuing what became F-35B.
Or that the carriers would be ditched as the price for a national Lo Interdictor.

However a wildcard option is doing a Rafale and trying to lure the USN post A12 and NATF cancellation onboard.

 

[FighterJock]

The Royal Navy would really have no option but to join the FOAS program and do a CTOL carrier capable variant and share the cost with the RAF in that scenario zen.

 

[red admiral]

If the UK went with the new build FOAS option instead of F-35, I don't think it'd be in service yet. No idea how it'd be paid for either during development in the 2000s and 2010s. Maybe stop buying Typhoon after the Tranche 1s?

Not sure which countries would be keen to partner on it.

 

[Hood]

Well the among the choices presented for Joint Force 2000 in 1998 were:

a) 220 P.151-02 FCAS, 3 smaller CVF with 60 JSF for the RN, 65 Eurofighters replacing Harrier GR.7 - cost £20.1bn
b) 329 P.151-02 FCAS, no CVF programme - cost £16.4bn
c) 3 CVF, 260 JSF, no FOAS - cost £15.7bn

*Note the P.151-02 was a non-stealth Eurofighter derivative, so for a full stealth like the P.158-06 posted in the FCAS thread you can easily add a a few tens of millions to the price tag.

The estimated costs do seem quaint when you compare with the real-world figures actually achieved.
- In 1997 the estimated Eurofighter programme cost was £17bn, by 2003 that had risen to £20bn, by 2011 the NAO were forecasting £22.9bn with total programme costs of £37bn
- In 2022 the estimated life cost for 48 F-35s was £18.76bn (at something like £84m a pop, 260 JSFs would cost at least £21bn today, excluding life costs)
- Two CVF cost £7.6bn in 2019 prices so three would work out at least £11.4bn.

So in effect, costing 329 FCAS Eurofighter variants in 1998 at £16.4bn compared with £17bn for 160 Eurofighters they were estimating a much lower unit cost for a Eurofighter-derived FCAS, probably reflecting the lower R&D cost.

Given that the RAF acquired 228 Tornado GR.1s - of which 142 became GR.4s and 24 GR.1Bs - option a) would seem to indicate a one-for-one Tornado replacement plus some reserve. At least 8 or 9 squadrons worth. It's not clear whether the 65 Eurofighters to replace the Harrier's is an additional order or part of the 160 total already committed. Even so that would be 380 Typhoons of various types.
Option b) with 329 FCAS would seem to indicate that all the Harrier GR.7 squadrons would be converted to strike (220 FCAS + 92 GR.7s = 312) so something like 14 strike squadrons. So the RAF would have something like 490 Typhoons of various types in 22 squadrons.

Could the UK go it alone?
Well if it was a Eurofighter-based programme, and assuming frontline numbers still fall broadly inline with historical, but ending up with perhaps a doubling of the Eurofighter order from 160 to 320, then you are looking at probably an extra £8-10bn on the Eurofighter programme, taking us to ~£47bn total programme cost, piggybacking off the Eurofighter R&D effort.

For something like the stealth P.158 the costs would be far higher - for example the unit cost of Typhoon is something like £73m, that of JSF is something like £84m. Assuming the P.151 unit cost some 30% lower than Typhoon (~£50mil [given £16.4bn for 329 aircraft the unit cost cannot be higher than £50m, and that leaves no leeway for R&D but sub-50m feels far too cheap to be realistic]) was even feasible, you could easily add £10m for the various LO features etc. I would be surprised if you could get a two-seat Typhoon FCAS for less than £73m in the real world and something like the P.158 would easily touch £95+m given its two-seater and twin-engined and therefore is intrinsically likely to cost more than an F-35, plus the lower production run to amortise the costs. You'd be looking at £15bn just to build 160 stealth FCAS, let alone the R&D costs. I wager you would spend something like the Typhoon programme all over again, perhaps up to £40bn with full lifecycle costs.

Of course, I'd be interested to see what figures are being quoted in the newly released FCBA files in relation to force options, which must include the more high-end options given the P.158 unearthed in the files by Sir Humphrey. So once I get a chance to look at those files no doubt I can refine my rough estimates above.