An interesting bit of history…

Probably one of the most famous engines used in WWII was the Merlin.

Few engines throughout history have achieved a near mythical status among its admirers. Fewer still can share credit for the rescue of an entire nation. Perhaps only the Rolls-Royce Merlin engine can claim both distinctions. During the Battle of Britain, it was the Merlin that powered the Royal Air Force Hurricanes and Spitfires that were England’s only effective defense against German air attacks. With the battle won, and the engine’s reputation thus established, the Merlin would become the stuff of legend and the powerplant of choice for numerous other aircraft.


14,000 parts, no that is NOT a misprint, 14,000!!! Hand fitted by Rolls Royce, and they dumped the contract on Ford of Britain and Packard in the US to build them. The interesting part?

Both Ford and Packard were mass production! So there were issues…

The article, HERE from Tested, is from 2015, but it’s still very applicable.  And it’s a neat one! Terry Dunn did a great job of researching and found some videos from WWII England that talked about the engine’s construction.

And before you ask, no these are NOT the same engines Packard put in the PT boats. It is similar, but the PT boat engine was developed inhouse at Packard, HERE. It’s also based on an airplane engine, but it’s the Liberty engine from 1925!

The irony? It’s 2018, and those 70+ year old engines are still out there powering Mustangs and Spitfires today!

And there are a few of the Packard PT boat engine still running in PT boats too!

h/t Stretch

And a hat tip to John up in Canada, he sent me THIS link. They’re still flying up there!


An interesting bit of history… — 12 Comments

  1. There is a machine shop a bit north and west from me (Gary, IN) that does rebuilds and repairs of these engines. They aren’t tuners, but rather (re) builders of worn/damaged engines.

    I have been amazed at the complexity and ingenuity in these engines.

  2. Both these Merlin engines, and the large radial engines were the high water points for gasoline aircraft engines.
    Much like the diesel would end the era of the steam railroad engine, the jet engine would end the era of the large reciprocating aircraft engine.

    An yet, when my wife and I are in the house and hear the sound of a large reciprocating aircraft engine we run out of the house to see what’s flying overhead.

    Very good post and the link was a great read.

    Thank you.

    • Same here. Stepped outside yesterday–it was a Beechcraft 18, likely out of Arlington Municipal. Depending on prevailing winds, we get a LOT of air traffic going over on approach to DFW, usually making a left turn from downwind to base.

  3. I worked with a CAF wing chief of maintenance who swore he would never, ever work on a Merlin again. It was too hard to get to various and sundry accessories and parts of the engine once it was on the plane. He’d retire first. Indeed, when the wing optioned for a Mustang, he passed the wrench on to another. Great engines, but a wee titch bit snug in the cowling and mount once you hang all the accessories on them. Even my little paw wouldn’t fit in some of the crannies.

  4. And when you hear one rumble by, in the air or on the water, and you can feel the rumble in your chest, it’s still the sound of freedom.

  5. Late 70’s in the Seattle area, the unlimited hydroplane race boats still used Merlins. My employer took over a winery complex next to the Boeing Development Center when the winery moved to Woodenville. We had excess space and rented it cheap to the boat racers. There were dozens of Merlins and a few Allisons stored there. My own private museum I could wander around at my leisure.

  6. B- Yep, and that’s 70+ year old tech!!!

    John/RHT- Yep, I still do it, although we don’t get many radials or piston engines up this way… sigh…

    TxRed- Oh hell yes, I’ve looked into one that they were working on at P’cola one day. Nope and nope! I’d probably get my hand stuck!!!

    Aesop- Exactly! 🙂

    WSF- No fair… LOL

  7. When NASM/Udvar-Hazy hosted a 100th Anniversary party for the RAF a Lancaster flew over our house. FOUR Merlins in sync. Pure bliss.

  8. Production of Merlins wasn’t “dumped” on Ford of England. Rolls-Royce had three factories producing Merlins, Derby which was the original factory, the shadow factory at Crewe, and the second shadow factory at Glasgow, which was built during the war. Rolls-Royce produced over 70,000 Merlins in its three plants, as well as the Meteor tank engine and the Griffon. In the autumn of 1939, the air ministry ‘suggested’ to Rolls-Royce that they consult with Ford, who were the recognized experts in mass production techniques and training masses of new employees to perform technically demanding jobs. When France fell Ford was given a contract and they started building their engine factory in Manchester. Eventually Ford produced 30,000 Merlins while Rolls-Royce produced 32,000 at Derby.

    Like the Mustang, the Packard Merlin originated as an RAF contract. Since Britain could not produce enough planes, engines or machine guns, the RAF came to the USA with bags of cash. Lockheed Hudsons, Consolidated Catalinas, Grumman Wildcats and Curtiss Warhawks were bought off the rack while the North American Mustang was commissioned by the RAF. They would have bought Lockheed Lightnings but the US government would not allow the export of the top secret turbo-chargers and without them the aircraft performed poorly. The British Purchasing Commission also ordered 50,000 .50Browning machine guns from Colt, to replace the 303Brit machine guns in the RAF armoury. The delivery of the Packard Merlins started in 1941 and they were sent to Canada to be installed in Canadian built Hurricane IIs. The delivery of all those machine guns were supposed to start in 1942 but then the Japanese attacked. The Mustang, the engine to make it great (the Allison engined Mustang Mk I was a dog at altitude) and the guns needed for it were all on the assembly lines waiting for the USAAC to scoop them up.

  9. Stretch- I’m sorry I missed that.

    Al- Maybe I could have worded that better! 🙂

    Ed- Agreed!

  10. If’n y’all wanna see how much HP can be extracted from a Merlin or Allison, get ye to a tractor pull.