FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1945
1945 - 2284.PDF
NOVEMBER 22ND, 1945 551 internal increases of strength to withstand higher boost pressures and r.p.m., and the use of Vandervell strip-type thin-wall bearings, this being the first occasion on which such bearings have been used in an aircraft engine with such high r.p.m. and heavy loadings. Disposition of the spark- ing plugs was also altered and ignition harness was re-designed to obtain more advantage from the high-altitude ignition equipment now fitted. Supercharger Modifications The double-entry supercharger impeller was replaced by a single-entry impeller of increased capacity, and the hydraulically operated two-speed clutch was re-designed to effect a saving of space and an increase in efficiency. Remodelling also included the addition of a boost pressure correction capsule to the boost-corrected ignition servo unit which, linked to the c.s.u. and thus responsive to engine speed, regulates the ignition timing for any engine operating condition. Perhaps the major modification of the VA over the previous marks was the replacement of the carburettor with Hobson-R.A.E. fuel injection and metering equipment, which embodies a fully automatic (Above) Warwick installation of theNapier Sabre VI with annular radiator. (Right) Graph showing performanceat altitude of the Sabre VII on 100 octane fuel. * Allows for drop in powerdue to weak mixture. duction and not to design. The prac- tice of using the linings immediately after manufacture robbed them of an age-hardening process, but an artificial hardening was introduced which satis- factorily overcame the trouble. The Sabre IIB was installed in the Hawker Tempest V, and this engine was closely followed by a Mk. Ill which was specially developed for the Blackburn Firebrand ; however, only 25 Mk. Ill units were installed, owing to the very high priority attached to the production of the Mk. V. A pre- liminary flight development engine for the Mk. V was known as the Sabre IV. Numerous modifications were in- corporated into the design of the Mk. V and VA, among which were TAKE-OFF CLIMBING COMBAT MAX. CRUISING MAX RPM 385O 3 7OO 385O 325O LB/SQ.IN. + I7i4 + IOK? + I7fc + 7 MOO. SUPERCHARGER MAX. 8 HP 3OOO 2235 3O55 17 3O ALTITUDE S L • 85OO 225O 8 5OO ruu. SUPERCHARGER MAX. B.H.P — I9602 76O I57Q ALTITUDE 18250 _L24SO 17000 32OO IO 12 14 16 18 2O 2? 24 26 ?8 3O 3? 34 ALTITUDE - THOUSANDS OF FEET 6ft. llin. Sabre from below, show- ing fuel pumps, double- entry air intake andcoolant pumps.
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
