orlov: did Spey help? Upthread I give:
27/2/64 P.1154B (RN) was cancelled as Ministers accepted overwater need for 2xengines, and that an Anglicised F-4-sort-of-J with reheated Spey would do the job, where J79 could not, due to worse response to slam reheat in the "bolter" case.
New Ministers 27/10/64 also declined Shorts Spey/Crusader; ordered 4xYF-4K, cash; and funded R&D, RB168-22R.
In Washington 7/12/64 UK was offered much, on credit, at fixed prices to DoD-standard.Treasury then, properly, opposed Anglicisation.
MoA briefed Ministers 5/65 that "improvement in certain Naval techniques” (HoC, 5/12/68: reheat into the wire) admitted J79, giving the option of reducing UK-peculiar costs and deferring engine £ cash into distant $ credit.
Ministers 6/7/65 ordered 20xF-4K, 2xYF-4M, (38, to be) 24xF-4M, all Spey, all on $-content credit/fixed prices. CAS had wanted more bog-standard F-4D-ish, but MoA Jenkins 17/2/65 caused P.1127(RAF) R&D instead. 60 ordered 29/12/66, kept HS Group in Aero.
MoD Healey 13/11/65 revisited J79's “£100Mn. saving”, but Jenkins prevailed, that Spey canx would do “harm to RR's intnl. standing” A.S.Bennell,Def.Pol.&RAF,MoDAHB,94,P.69. 26/10/66 all Spey/$-credit (35, to be) 28 more F-4K, (124, to be) 92 more F-4M were ordered.
HSAL enjoyed decades of Sister Firm business; Shorts won outer wing fabrication...but:
the overriding causes for spending so much on Spey (that, by 5/65, neither RAF nor RN wanted/needed), were:
HoC was told 5/12/68 Spey 202 was "to sustain RR as" techno-leader (by then they had RB211/L-1011 and were bidding MRCA); and:
fabrication of UK-peculiar, engine-related structure (aft fuselage/tail/wing parts) kept BAC Preston afloat post RAF Lightnings, so sustaining their credibility, to win 21/12/65 Letter of Intent, 5/5/66 contract (to be £1.5Bn) for Saudi Arabian Air Defence Scheme.