FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1938
1938 - 1413.PDF
May 19, 1938. Supplement 502a E AIRCRAFT ^~V. ENGINEER No. 14S. 5 ) Year May 19, 1938. QUANTITY PRODUCTION AT FILTON How the Bristol Blenheims Are Erected Illustrated mainly with "Flight" photographs. THE production in quantities of a modern militaryaircraft may be said to divide itself naturally intotwo stages: the fabrication of the individual pieces and components, and the erecting of these com- ponents into the complete aircraft. With the extensive use of stamping and pressing which the magnitude of present-day orders has made possible, the former stage is not usually the one which causes the production en- gineer's hair to turn grey prematurely. The delays are far more likely to occur in the second or erecting stage. No mention may be made of the actual number of Blenheim medium bombers already delivered to squad- rons of the R.A.F. by the Bristol Aeroplane Co., Ltd., but it is common knowledge that the number is very con- siderable. This fact, coupled with the exceptionally high performance of the Blenheim (280 m.p.h. or more at 15,000ft.) lends particular interest to the assembly methods employed at the Filton works. Space does not permit us to deal here with the initial manufacturing processes, but, as mentioned above, it is the assembly period which is the real "bottle-neck" of production. Without going into a detail description of the con- struction of the Blenheim, it is necessary to point out that the fuselage is of the semi-monocoque type, with a skeleton of formers and stringers covered with light metal sheet, while the wing is a cantilever of the two-spar stressed-skin type. It may be recollected that some years ago Mr. H. J. Pollard, now in charge of Blenheim production, referred in one of his articles in The Aircraft Engineer to the subject of '' developable surfaces.'' The term was used to describe an external form of fuselage or other aircraft component which, although tapering, had no double curvature. By avoiding the double curvature the metal sheet used for the covering can be applied in large panels without necessitating panel beating or other methods of shaping, and can, in fact, be "wrapped" around the fuselage. In the Blenheim fuselage use has been made of developable surfaces, and the sheets are quite large, but, of course, reinforced by internal stringers. ; '_•• Simplification '•" The rear fuselage portion (Fig. 1) is built as a unit on special jigs and it might be mentioned here that the Blenheim construction is slightly unusual in that the Omega-section stringers are not attached to the formers, into which they are notched, except via the outer skin. This system results in a considerable saving of work, and has been found quite satisfactory. The stringers, by the way, have their closed side riveted to the skin, the edges being free. When the front fuselage portions leave the jigs on which they are assembled they are passed to the bottom of the erection line and mounted on trestles, as shown in Fig. 2, Fig. 1.—The rear fuse-lage portion of the Blenheim is an all-metal semi-monocoque structure. It has "de-velopable '' surfaces.
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
