AviationBanter - View Single Post - F-35's Costs Climb Along With Concerns

mike Williamson

wrote:
In article ,
(Ricardo) wrote:

Incidentally, a few sources have claimed that the Packard
built Merlin, whilst a superb engine, lacked the power levels
of the Rolls Royce version. This, it is claimed, was because
the British kept secret the composition of the phosphor-bronze
bearings that they used in the engine.

The Packard Merlin did differ as far as I know but also as far
as I know it was not because of secrets. The British versions
were to closer tolerances requiring much more skill in assembly.
In "Sigh for a Merlin" a fault called skew gear failure was
traced to a difference in assembly order from Rolls Royce in one
of the (British) shadow factories.

In fact the Rolls Royce tolerances were rather looser than those
used by either the British Ford Motor Company or Packard. Rolls
Royce used hand fitting to match up parts, whereas Ford and Packard
were mass production companies which relied on close tolerances so
that parts were interchangeable without the laborious fitting and
adjusting that Rolls Royce used. The Rolls Royce system did require
a higher skill in assembly due to these fitting requirements.

Mike