FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1942
1942 - 1997.PDF
«nqj SEPTEMBER 24TH, 1942 FLIGHT 333 there is no one better able to study and combine all rhese requirements than the full-time experts and instal- i iation designers of the engine manufacturer. Such tech nicians have, at their command not only experience gained frcrfrf their own test flights, but the additional ex perience gained from the behaviour of the power plant and previous power plants in service on various types of aircraft operating under all sorts of conditions and climates in the various theatres of the war. It should be added that all the engine cowlings are interchange able as they are made on jigs and checked on reference jigs- One of our latest aircraft that makes use of the inter changeable standardised power unit is the Avro-Lan- caster bomber, and photographs of the Rolls-Royce Merlin installations accompany these notes. In a recent article which appeared in tluVjournal on the estimation of take-off weight for a heavy bomber, the author states that for two identical aircraft of the same gross weight the bomb load varies as much as 50 per cent., the fuel and oil load being the same in both cases. The author goes on to say that to balance the difference the engine weight must be considered. It appears, then, that here is another advantage of the standardised power unit, for if by a rapid change of the engine installation the bomb load can be considerably increased for the same range, then for certain operational/ duties this is certainly a great asset. A CAPITAL SHIP Martin Baltimore Doing Good Work in Middle East SINCE the prototype made its first test flight on June 14th of last year, the Martin 187, known to the Royal Air Force as the Baltimore, has gone into large-scale production, and recently the type has figured in the news from the Middle East, where it has been doing very good work. The Baltimore is classed as a medium bomber, but with the increase in bomber size we may soon come to look upon it, and others of similar size, as a light bomber. In any case, the Baltimore was designed for speed rather than for heavy bomb loads, as its small size and clean exterior indicate. Its family resemblance to the Martin Maryland is obvious, although differences in the arrangement of arma ment have changed the silhouette outline of the fuselage, the "expansion" having taken place both in an upward and in a downward direction. The careful fairing of the upper gun turret is in marked contrast to that of the Maryland, in which there was a rotatable dorsal turret. The very pointed nose of the fuselage should provide '• much better entry for the air than did the rounded nose of the Maryland, and the fitting of two Wright 14-cyl., double-row Cyclone engines in place of the twQ P. & W. Twin Wasps has given a very substantial increase in the power available. All these factors together have resulted in a great increase in spe*ed (315 m.p.h. compared with 275 m.p.h.). At a speed of 2,400 r.p.m. the take-off power of the Wright GR2600-A5B engine is r,6oo h.p. At sea level the power is 1,350 h.p. at 2,300 r.p.m., and with the blower in low gear the power is the same at the same speed and 5,000ft. With the blower in high gear the Cyclone 14 develops 1,275 h.p. at 2,300 r.p.m. at IT,500ft. Other engine figures of interest are: compression ratio, 6.30:1; blower ratios, 7^4:1 and 10:1,
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
