Thread: The Avro Shackleton

JD, according to Rolls Royce historians the Merlin & the Griffon were two separate engine families with little in common other than having 12 cylinders. They rotated in opposite directions for a start. Merlins had an internal and complex accessory drive. Griffons had an external shaft driven auxiliary gearbox for accessories. The Merlin was developed from the PV12 (Private Venture 12 project) of 1930. The Griffon was developed from the Buzzard and the "R" (racing) engine form the Schneider Cup competition. Griffon development was suspended in the thirties to give priority to the development of the Merlin. both Merlins and Griffons had an amazing variety of supercharger systems as development proceeded. Stages, single and multi speed drives, intercoolers etc. varied from Mark to Mark for various reasons, improved performance at take-off, at high and low altitude, improved ceiling, and special purpose engines.

Jeffrey Quill, the Supermarine test pilot said that his favourite Spitfires were the Griffon versions.

The Griffon 58 was the final Mark of Griffon which was produced until 1955 for the Shackletons. The last delivery to the RAF was, incredibly, in 1986 but this was a factory rebuild not a new engine. The later Marks of Griffon were noted for their reliability and durability usually reaching their scheduled life of 2,000 hours without problems. Compare with the "R" engine which had a service life of one hour!

Originally Posted by kiwiventurer

Thanks bob10, really enjoyed that.
36 litre V12 at 2 ton,..... repower anyone?

The Packard V12's used in PT boats and other small craft of WWII were just a tad over 40 litres. I have no idea of their weight. The PT boats used three of them. Imagine the fuel bills. Hall & Scott made 36 litre V12's that were also used in small craft. Nev. Morris has made a "hot rod" tow truck using one.

Slight highjacking here, but, on the flipside of my ridiculous repower comment, a couple years ago my uncle sold the 4lt Rover V8 from his Disco 2 to a guy who was going to use it in his homebuilt plane. The engine gets inverted and the sump cut off and a remote oil resevoir goes further back in the fuselage! Would sound good. 👍

Originally Posted by kiwiventurer

Slight highjacking here, but, on the flipside of my ridiculous repower comment, a couple years ago my uncle sold the 4lt Rover V8 from his Disco 2 to a guy who was going to use it in his homebuilt plane. The engine gets inverted and the sump cut off and a remote oil resevoir goes further back in the fuselage! Would sound good. 👍

Are they allowed to be used without twin ignition?

USA replica makers of 2/3 scale Spitfires and Mustangs use a 540 cubic inch aluminium Chev big block with special dual ignition heads, one magneto and one electronic. They also have a whacking big engine driven centrifugal supercharger. I have seen (and heard!!!!) one on the dynamometer at Van Dyne Engineering in LA. Google them. The torque reading went off the scale at 1640 ft/lbs. This was a special version that Stew & Tres built for a customer building a street rod and was in a far higher state of tune than the aero version. Even with ear muffs and through the walls of the dyno room, one could still hear and feel the noise. One wonders what transmission the builder was going to put behind it.