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Redwulf__26
01-18-2006, 03:46 AM
I received this from RR

Hello Andy,
This is quite a difficult question actually, and neither I nor my colleagues
have seen any written or scientific reason for it.
Talking big engines only, RR traditionally built upright Vee engines from
1914, as did Allison in the US, so for RR it was a continuance. This was
well before the German industry was permitted to restart after WW1. I can't
comment on Russian engines as I have very little knowledge of them.

However, the story goes that in the early 1930s a Luftwaffe delegation which
visited Britain to bring their industry up to date (and obviously crib as
much as they could!) were invited to RR. At the time the configuration of
the PV12 (which became the Merlin) was under discussion and a wooden
inverted model had been made. The Germans were shown this and, though the
PV12 was built as an upright, they thought this must be the way to go, went
home, and got Daimler Benz and Junkers to produce their inverted designs.

As all these types are 'dry sump' so in theory could be engineered to run
either way up.

The German predilection for a cannon firing through the propeller axis may
also have effected their choice of configuration. With the cannon barrel
lying between the cylinder banks, the cannon itself would be mounted lower
and hence be less intrusive into the cockpit in the inverted design.

I'm sorry I can't give you a cast-iron reason, but hope this helps.

Regards
Peter Kirk
Rolls-Royce Heritage Trust - Engine Data

:-))

Redwulf__26
01-18-2006, 03:46 AM
I received this from RR

Hello Andy,
This is quite a difficult question actually, and neither I nor my colleagues
have seen any written or scientific reason for it.
Talking big engines only, RR traditionally built upright Vee engines from
1914, as did Allison in the US, so for RR it was a continuance. This was
well before the German industry was permitted to restart after WW1. I can't
comment on Russian engines as I have very little knowledge of them.

However, the story goes that in the early 1930s a Luftwaffe delegation which
visited Britain to bring their industry up to date (and obviously crib as
much as they could!) were invited to RR. At the time the configuration of
the PV12 (which became the Merlin) was under discussion and a wooden
inverted model had been made. The Germans were shown this and, though the
PV12 was built as an upright, they thought this must be the way to go, went
home, and got Daimler Benz and Junkers to produce their inverted designs.

As all these types are 'dry sump' so in theory could be engineered to run
either way up.

The German predilection for a cannon firing through the propeller axis may
also have effected their choice of configuration. With the cannon barrel
lying between the cylinder banks, the cannon itself would be mounted lower
and hence be less intrusive into the cockpit in the inverted design.

I'm sorry I can't give you a cast-iron reason, but hope this helps.

Regards
Peter Kirk
Rolls-Royce Heritage Trust - Engine Data

:-))

LameDuck.
01-18-2006, 10:03 AM
http://forums.ubi.com/images/smilies/25.gif

LEBillfish
01-18-2006, 11:05 AM
Kewl.....

Airmail109
01-18-2006, 11:08 AM
Huh what an awesome response! http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

p-11.cAce
01-18-2006, 11:10 AM
yeah cause we all know that anything good that the Germans had MUST have been stolen or copied from someone else - especially a paragon of engineering brilliance like Britain http://forums.ubi.com/images/smilies/53.gif
The inverted vee aircraft engine goes back at least as far as the Liberty 12-A which was used in the Loening OA-1 of 1926.http://www.wpafb.af.mil/museum/engines/eng29.htm