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Photography by Robert D. Archer from the late 1940's to the 1980's.
Images in this secton are Copyright Robert D. Archer and are managed by Victor G. Archer/Archer Aviation Photography and Historical Archives.
You guys are embarassing me!! your interest in, an ability to digest, copious quantities of very specific information about a relatively obscure piece of history is simply amazing!
I remember a line from a movie.. "where do we get such people"... they're still here guys! Just waiting for a nudge from the right place...............
While the Sabre is an interesting piece of history, most of us realize that we will never see one operating, much less in the air. Possible, yes, but the chance is very remote. Building 980 special tools is a major project itself.
JAW I have to say your enthusiasm seems unbounded. A project like this is probably well suited for a Jay Leno/Mike Nixon tag team. )
OK guys lighten up on the future of the engine
First off we don't need 980 tools to get the engine flying. Most of the tooling is for major repairs of a worn out engine. The reality is that we would take the engine apart, inspect things, do the clean and paint, replace the seals and gaskets, put it together, do the ignition and fuel systems and run it.
On racing it, it was running at close to its peak at the time. The small bores allowed the high RPM. The supercharger is one stage and gave 9.5 #'s of boost. It is a small diameter high rpm fan and there is not much more to add there. More rpm and the tips go mach+ which = heat and noise and less HP. The displacement absorbs everything the blower can give out. To make more HP means more boost. ?bigger fan, add a turbocharger more pipes and weight, more rpm, more issues.
Apples to Oranges time, at what attitude did the max speed happen? Compare the max speeds of all the aircraft and you will see that they are all over the place for altitude. In other words you pick the best alit to clock the aircraft. Reno is not th e optimal place for top speeds. The best I have seen was hot and sunny with a density alt of around 9500 feet.
Strega's engine is set up with the shift in low speed. If we put the clutches back in and run at 20,000' we would get close to 600mph ground speed. Which means nothing in the record books or at Reno.
I have also done some Centaurus engines and am expermenting with some ideals there. Big difference with air cooling and liquid on the max power you can get. RPM is a killer with the big radials. The loads the master rod bearings get with high rpm is amazing for a few seconds!
We ran 38% gears on dago and strega in the first years, but the rocker arms/springs dissolved. The engine did make some HP at 3800RPM though. The small gear tended to dissolve between 400 and 500 miles of racing. That was a bit of a problem. There are lot of places to improve things but each change effects everything else and not always to the good.
Later
Kiwi ace Jim Sheddan, in his book 'Tempest Pilot' provides a service use
comparison between Merlin & Sabre..
"A Merlin, by comparison was a slow revving motor, cruising revs being
in the vicinity of 1,800rpm while maximum revs were in the 2,800 range..
..Thus there was a flat spot between the pilot asked for maximum effort
from his Spitfire & when he received it..
..This time lag could be crucial when bounced by the enemy..
..The Napier Sabre, by comparison, cruised at 3,500rpm & had a maximum of 3,850..
..There was so little difference between cruising & flat out that it could be claimed that
a Tempest was operating at its maximum performance at all times..
..This had an advantage in that it was difficult for enemy fighters to get in a position
to bounce it..."
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