On Fri, 05 Oct 2007 08:26:27 -0700, "Scott M. Kozel"
wrote:

The Merlin 61 used in the initial Spitfire IX's was also a
modification of the Merlin design. The fact remains that the V-1650-3
and -7 were two-stage Merlins produced under licence by Packard.

That is partially true.

No, it's completely true.

Packard modified the turbocharger to produce
more high-altitude power,

1. The V-1650-3 and -7 used two-stage, two-speed supercharging driven
from the engine crank, not turbo-charging.

2. The gearing ratios on the supercharger and the compression ratios
were generally no different to that on the Merlin 60 series. The only
commentary I have ever seen in relevant British contemporary records
recorded a 1,000 feet lower full-throttle height for the Merlin 266 in
the Spitfire XVI. Other than that, the only comment by end-users I've
seen was criticism by pilots in 145 Wing in Belgium who converted to
the Spitfire XVI and complained that they produced less power at low
altitude than the Merlin 66-engined Spitfire LF.IXB's that they had
used previously. For a while their wing leader continued to fly his
LF.IXB for that reason. However, I think it's pretty clear that the
RAF didn't consider this a major problem and I would agree with them.

and modified the alloys of some of the major
engine components to adapt the engine to U.S. mass production
engineering and processes. The Rolls-Royce Merlin engines were hand-
built.

No, they were mass-produced at several factories in Britain, notably
Trafford Park in Manchester and Hillingdon outside Glasgow as well as
the original Rolls-Royce production lines at Derby and Crewe. The
Derby works spent considerable time on R&D which involved disturbing
volume production, but this was not true of the other sites.

U.S. mass production processes allowed vastly greater
quantities (over 16,000) of the V-1650 to be built in a timely and
reliable manner.

You should check out British production of the Merlin before making
this kind of inaccurate comparative assertion.

Packard added considerably to the design of the
engine, which includes and is integral with its production processes.

Packard certainly made modifications to the engine to account for the
use of US anciliary equipment such as coolant pipe clips and pump
drives - well, at least after delivery of the first batch of them to
Britain without that equipment.

If there was no P-51 then some U.S. company would have greatly
accelerated the production of something of similar performance.

So demonstrate this, based upon the historical evidence... I'm not
being antagonistic (although it might sound like it), just pointing
out that assertions which don't take into account the historical
reality aren't that valuable.

Both the U.S. and the British each produced a number of excellent
advanced warplanes in WWII. In a universe without the P-51, certainly
something else of similar performance would have been produced.

There certainly would have been more urgency to get something going;
however the options were limited.

I suspect a second production facility for the P-38 and a major
engineering drive to sort out the engine and aerodynamic problems were
the most likely, alongside stuffing more tankage in the P-47 and
something more than a token gesture at doing the same with the
Spitfire. However, none of these would have produced an answer in the
same time-frame as the P-51 did.

Gavin Bailey

--
Solution elegant. Yes. Minor problem, use 25000 CPU cycle for 1
instruction, this why all need overclock Pentium. Dumbass.
- Bart Kwan En