Design of the Typhoon fuselage bridged the gap between the classic Hawker Tube structure and what is now regarded as orthodox stressed skin construction. Retaining the tube structure for the centre section provided easy access to the monster Sabre engine and various systems by simply removing cowl panels, it also provided for quick replacement of damaged structural members.
Tube structure is built around heavy spanwise spar bays that connect the main planes through the fuselage structure. These spar bays are connected to the cockpit structure through girder style steel tube construction either squared and bolted at connection points, or fitted with steel plug ends for direct bolting.
Construction aft of the cockpit is that of a monocoque design built from frames and stringers, these two sections are connected through a tubular integrating structure bolting to reinforced attachment fittings on the monocoque’s forward most frame.
Each wing for the Typhoon is constructed as a complete assembly that is bolted directly to the spar members of the forward fuselage. Main structure for the wing consists of two main spars and six primary interspar ribs, the outermost main rib being the only flanged alloy sheet rib, and the one to which the detachable wingtip is secured.
The wing tapers in thickness from root to tip in thickness and chord, the lower surface of the wing inboard of the dihedral is horizontal, while the upper portion tapers towards the dihedral joint and creates a slight anhedral.
Wing spars are built individually and consist of three main sections. The inner portion between the wing root and the dihedral consist of heavy TT section extrusions with girder style “U” shaped extrusions between upper and lower booms. The centre spar section consists of slightly lighter TT section extrusions joined by a double alloy sheet web riveted to the outer faces of the tongues of the TT booms. The third section begins at the centre of the gun bay for the front spar, and at the end of the gun bay for the rear spar; this section consists of T section booms joined by a single heavy gauge alloy sheet web.
Leading and trailing edge ribs are attached to front and rear spars in separate assembly fixtures which are later combined with the interspar structure in the main wing jig. Wing skin panels are assembled incorporating stringers for direct application to the wing structure.
Cowling and Decking: