R.R. vs. Packard

[jetsrforkids]

So what are the main differences between a R.R. built Merlin vs. a Packard? Do all the parts interchange and is one considered better than the other?

[Snake45]

I've read a couple places that the Packard-built product was considered superior, but I don't have thirty seconds actual experience with either in any way so I'm not qualified to say.

[shrike]

I seem to recall that part of the licensing agreement was that the engines be interchangeable as a whole. The equivalent Mk or Dash of Merlin should be able to be dropped in to the same airframe, whether it was RR or Packard built. The individual components are not necessarily interchangeable. Packard made a lot of changes to facilitate mass production of the engine including different bearings and provision for the use of many more gaskets than RR.

[51fixer]

A subject that could fill volumes.
1st there were several dozens of different models built from both and even Ford in France built them
RR produced the Merlin from latter mid thirties through late 40s for post war versions.

A great series of books by Rolls Royce Heritage Press you should check out on the Merlin.

[JDK]

Easy. If you're in the UK, the RR Merlin is better, even if a Ford built one*.

If you're in the USA, Packard Merlins are better, while you put an RR (not Packard) sticker on your Mustang's engine cowl.

For those after facts, as Rich suggested, see the following PDF from the Rolls Royce Heritage Trust, several covering Merlin stuff:

http://www.enginehistory.org/Reviews/R- ... erForm.pdf

I must see if I can get permission to publish online the very popular Warbirds Worldwide article 'Reinventing not Fixing' on the development of the Packard Merlin.

Regards,

*Ford of Manchester: http://en.wikipedia.org/wiki/Rolls-Royc ... Production

[Invader26]

Commonwealth Aircraft Corporation [CAC] built Merlins in Australia for locally produced Mustangs and Lincoln bombers...

[51fixer]

I have a small catalog of interchangeable P/Ns for parts.
Haven't looked at it enough to know what it has listed.
So yes, there are some.

Packard built US versions V-1650-1 (Single Stage Blower),3,7,9(All 2 Stage, 2 Speed Blowers) But many parts from one Packard Version won't fit another Packard Version, and the -9 was very different than the earlier models.

Some of the exotic Blended Engines used in P-51s and Air Racing have a RR Transport Crankcase with a -9 Packard Blower fitted by changing and adding the studs at the rear of the crankcase. This fits a Blower that has a Carb (Bendix) in the proper location to fit the Induction Trunk and eliminates the RR Fuel Discharge System.

[Richard W.]

As an aside, one of the "Lancaster at War" volumes (can't recall which) has a chapter written by an RAF mechanic who says that they loved getting Packard Merlins because each one shipped with a set of high quality tools in the crate, much better than the ones the RAF issued.

[John Dupre]

I've read that part of the reason for a poor reputation in early Packard built models is that RR provided earlier blueprints which Packard followed not knowing that certain parts had been strengthened or otherwise changed so Packard built models with known and previously fixed problems. I have also read that RR was still at heart a hands on shop and it was possible for workers on the assembly line to walk over to the casting or machining shops and discuss a problem and have it fixed without any kind of engineering change order or change to the blueprints. In the end each shop built superb engines each in their own inimitable way.

[JDK]

John, have a read of the Wiki page I referenced above. What you say is bits of the story, but they don't apply to 'RR Merlins', because the UK end of the manufacturing was much more diverse than a couple of sheds with fitters in one and engineers in another!

But there's a nugget of truth to the refinement 'in shop' and hand fitting approach at the RR Derby works - but not at Crewe, Glasgow et al.

The 'data lag' of design changes was a common issue in the period and a factor even in shadow factory production in the same area, let alone across the Atlantic. Some was a lack or recorded data, but in the case of the Merlin, given there were also UK shadow factories, and as I said above even a Ford factory, that would not affect the Packard organisation alone.

That said, most would agree that the UK aero-industry was, until the development of shadow factories with semi- and unskilled labour, culturally a much more 'skilled worker' rather than building the skill into the machine mass production approach, which was the model the US followed in W.W.II.

That also said historian L.T.C. Rolt rejected working at Crewe because he saw it as a depersonalised and deskilled machine, which actually says a lot about what you see and a lot about you (in Rolt's case he was a late 'arts and crafts' engineer in a sense) and not necessarily an objective assessment of the subject.

I'd also say that the US expanded the production infrastructure incredibly quickly and incredibly effectively, even with the lead in of European purchase and lend-lease of 'pre-war' materiel. The UK's gearing up, even with the expectation of an expansion capable structure had a remarkable number of hiccups from prima donna owners, industrial action and governmental and factory slowness. But then no US factory was ever bombed by the enemy, nor all the surrounding issues that the British 'got on with it' under.

It's a fascinating area, but when reading about it watch for the partisan bias in too-much of the general writing on the topic. There were cultural differences (from the level of spelling and vocabulary, like this post with 'organisation' and 'labour') to actual industry approach. However watch out for the theme: 'ours good, shortcomings their fault' which gives away someone with a home-team bias, and thus data to be wary of.

Regards,

Last edited by JDK on Sun Jul 20, 2014 11:35 pm, edited 2 times in total.

[JDK]

Commonwealth Aircraft Corporation [CAC] built Merlins in Australia for locally produced Mustangs and Lincoln bombers...

Indeed, but I don't think we'll get the debate to go triangular!

Much of the CAC Lidcombe NSW Merlin production seems to be obscure - how much was new of the engines, and even how many were built - 180 or 108 - get quoted. (Numbers were low because production was cut short by the war's sudden, nuclear ending.)

Regards,

[AvroAvian]

CAC Lidcombe only produced the Merlin 102 for use in the GAF built Lincolns. The Merlins used in the CAC Mustangs were either Packard V1650-7 from the USA or the RR Merlin 70, fitted to the high altitude Mk 23 and were engines converted from Spitfires Mk VIII. I don't have the specific numbers at hand here, but it was an exam question many, many moons ago...

[JDK]

Think the Aussie contingent need to work on how the Australian-built Merlin is vastly superior to any other nation's Merlin, Kestrel, Allison, Teasmade and Espresso machines' schtick.