FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1955
1955 - 0683.PDF
FLIGHT, 20 May 1955 681 (Left) With the tail section, and therefore the rear engine sup- port, removed, the engine is supported at the fuselage break by an external rig. The end of one fuel tank is also visible here—in the bottom-left section of the end-frame. (Right) The braking parachute is stowed in a compartment under the tail. On release, the cable strips around the fuselage port side, from beneath the flaps seen aft of the tailplane, and streams from a pick-up beneath the rudder. The ribbon canopy was illustrated last week (p. 661). SUPERSONIC FIGHTER . . . (i.e., in the rolling plane). The ailerons were mounted wellinboard, over the greater part of the trailing edge, in the position normally occupied by the flaps. It was found that, with thetype of wing chosen, not enough flap could be fitted to justify such surfaces. This is undoubtedly a factor which will becomemarked on all highly swept machines, a British example being the Gnat; on such machines the length of trailing edge availableis very limited, and the size of flap possible is not enough to produce a worthwhile gain in lift or change in attitude. On theother hand, the inboard ailerons minimize the wing twisting moment, which can be excessive on a very swept wing with con-ventional ailerons. Having no flaps, and owing to the considerable sweep angleand high-speed profile of the wing, it was decided to fit full-span automatic leading-edge slats. These should not be confused withleading-edge flaps or with a drooping leading-edge; the F-100 has true Handley Page slats, and their incorporation has resulted in anotable increase in available lift, a decrease in manoeuvring drag and better stability at high lifts. The F-100 can fly at an appar-ently impossible angle of attack—again a feature characteristic of highly swept wings—at a speed not unduly greater than that forthe F-86. Actually, the F-100 wing loading is lower than that of some recent F-86 models. On the other hand, the wing loadingis still sufficiently high to take the edge off the performance at top altitude; British fighters are generally less weighty than theirAmerican counterparts, and as a result perform better at over 40,000ft. The structure of the F-100 wing is such as to permit relativelyeasy and rapid manufacture by a factory equipped with very large and capable tools. Major loads are taken by two root-to-tipspars which, with an immensely thick, screwed-on taper skin, form a massive box between about 20 and 60 per cent chord. Betweenthese spars lie four other full-depth spanwise members, with sheet webs braced by vertical stiffeners. These four subsidiaryspars cease about two-thirds of the way to the tip, and the outer wing is of comparatively light construction. The skin, however,is continuous to the tip, the outer part being flush-riveted. The leading and trailing portions of the wing are much lighter in con-struction, and the front upper edge of the forward (main) spar has a full-span piano hinge, identical with that of the F-86, uponwhich is hung the leading-edge structure, which hinges for access to the interior systems. The ailerons are each made in two parts, and they are fullypowered by irreversible jacks bolted to the rear face of the rear spar. Control linkages run down the leading edge to a pointopposite the jacks. There are no tabs anywhere on the aircraft. The slats run out on massive forged cantilevers which are locatedbetween pairs of rollers. These forged supports do not, how- ever, retract into perforations in the spar web, as they do on theF-86. Slat incidence is controlled by a tubular strut attached to the inside of the slat leading edge at each main attachmentpoint. There are five slat sections on each wing, one more than on the F-86. At the root there is a heavy chordwise forging of I-sectionextending from the rear spar to well forward of the front spar. This root member is kinked, and projects into the fuselage atits rear end. Main spar loads are carried across the fuselage by a carry-through member; there is also a large cut-out in theunderside of the fuselage which accommodates the rear spar carry-through member, a less-swept beam mounted farther aftand, between the two, the wheels of the retracted undercarriage. The fuselage is readily divided into two portions, at a "break-point" just behind the wing. By removing the rear section, unrestricted access is provided to the whole powerplant up to,and including, the combustion chamber. During erection, the engine is mounted in the main fuselage, with some 15ft of engineand afterburning jet-pipe hanging cantilevered from the break- point bulkhead. The whole assembly is then lifted from a roofcrane and lowered on to the wing, the rear fuselage and tail being added later. When the rear fuselage is attached (by means offour self-aligning connections) it carries the rear end of the after- burner, so that the latter is not cantilevered in flight. Duringground running, with the tail off, the engine is supported by a special truss which clamps on top of the fuselage and preventsthe engine from whipping about (see detail sketch). The ducting is remarkable. North American chose a nose inletfor several reasons, chief of which they describe as "minimum complication plus excellent recovery under anticipated flight con-ditions; not subject to problems associated with side inlets; and desirable from standpoint of location of equipment, engine, etc."Certainly a nose inlet is best during flight at varying angles of attack or when yaw might be present; again, it is the best super-sonic intake. On the other hand, the duct length is necessarily very great and losses are proportional to duct length; again, Drawn to the same scale, these side views immediately disclose the differences in size and shape between the F-100 and its forebear, the F-86E Sabre.
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
