Ford Authority

Ford Once Redesigned And Built Rolls Royce Airplane Engines

Outside of the fact that both make automobiles, Ford and Rolls Royce don’t really share a whole lot in common – save for the fact that someone tried to transform a first-gen Lincoln Aviator into a Rolls-Royce Cullinan lookalike last year, and that particular vehicle was posted for sale a short time later. Otherwise, Rolls is a maker of low-volume, ultra-luxurious, and ultra-expensive automobiles. However, Ford did cross paths with the British icon back in the early 1940s when the latter asked the former to help it build its Merlin line of airplane engines, according to The Aviation Geek Club.

Rolls Royce Merlin Airplane Engine

Back in 1941, Ford operated two assembly plants in the UK that were capable of building these engines, which at the time were used in British fighters and bombers such as the Supermarine Spitfire and the Hawker Hurricane. However, as Rolls Royce supercharger designer Stanley Hooker recalled in his book Not Much Of An Engineer, The Blue Oval took one look at the Merlin’s technical drawings and stated “we can’t build an engine to those tolerances.”

Hooker immediately assumed that perhaps Rolls’ tolerances were too tight for Ford’s liking, but that wasn’t the case at all – it was quite the opposite, in fact. “No, they are much too loose,” FoMoCo replied. “We use much tighter tolerances for car engines so all the parts are truly interchangeable without any hand adjustment needed.” Instead, Blue Oval engineers went so far as to redesign the Merlin engine and make improvements, and by 1944, it was cranking out 400 of those powerplants a week – a number that reached a total of 30,428 before Ford stopped building them.

Supermarine Spitfire

Hooker himself admitted that Ford’s Merlin powerplants “were very good engines,” but interestingly enough, the fact that The Blue Oval was able to redesign it in the first place with an eye toward mass production has somewhat been lost through the course of history – until now, that is.

We’ll have more Ford-related history to share soon, so be sure and subscribe to Ford Authority for comprehensive Ford news coverage.

Brett's lost track of all the Fords he's owned over the years and how much he's spent modifying them, but his current money pits include an S550 Mustang and 13th gen F-150.

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  1. RWFA

    Similarly, the British Sourcing Commission was looking for more production capacity in the USA.

    Ford was on tap to produce them until crazy Henry put the kibosh on that.
    So the project went over to Packard (who was perhaps the closest global competitor to R-R).

    Packard had extensive experience with aero engines but when Rolls came calling Packard was focussed on auto engines.

    The Packard boys did extensive redesign in close consultation with Rolls. Every Packard improvement was rolled into the designs in the UK.

    One feature Packard introduced was indium plated journal bearings (an innovation pioneered by GM).

    In the end, the mass-produced Ford & Packard upgrades resulted in the Merlin becoming a very dependable engine with longer service and rebuild intervals than the R-R designed and craft-produced engines.

    The engines produced in Detroit went into the P-51 mustang and Canadian built Mosquito fighter/bombers and Lancaster heavy bombers.

    And these engines are not known as Rolls Merlin’s. They are Packard Merlins and have significant other design and hardware.

    1. The Retired Viking

      Didn’t they also find a home in PT boats?

      1. RWFA

        I think the PT’s used a pure Packard engine, not a RR design.

        The Merlin was modified by RR for British battle tank use and marketed under the Meteor name. It wasn’t in widespread use tho. (I saw one of these painted bright yellow still mounted in its original wooden pallet at Duxford a decade ago, my recollection is it may have had a wet manifold as well.)

        Interesting write up on meteor here:

  2. ViperACR

    Nice job, RWFA. You actually created some interesting and informative posts here without insulting anyone or being an arrogant a-hole. You should be this guy more often.

    1. RWFA

      Don’t be a silly boy rooting for, or be one of, the bad faith K-street tag team troll farm or the dystopian delusionals and you won’t get a sharp rebuke from me.

      By the way, I’m unaware of you ever contributing anything before. Try to step up sometime.

  3. FOG

    Not lost. Rather, ignored. Likely to reinforce the media’s decades-long anti-Detroit/anti-domestic slant and narrative.

    1. RWFA

      It was never lost. Folks who know about these engines or the planes they went in know this history well.

      And as for your nonsense “ignored because anti-Detroit”, both pffft and meh.

  4. grumpyunk

    Ford, designated the Aircraft Engine Division, built radial engines, the R-4360, in the former Dodge>Tucker plant in Chicago. Previously the R-3350 was built, by Dodge, in the same plant and used in the B-29. I believe the final engine Ford AED built was also in the same plant, and used in the B-52, the J-57 turbojet. Dad worked on them all.


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