Airframe production materials
The Materials which were selected are light alloy Hiduminium – RR58 (in several forms), high temperature steel, stainless honeycomb and resin-bonded glass fibre.
Hiduminium –RR58, which is sold in France under the designation AU2GN, was developed by High Duty Alloys Ltd to meet the need for improved wrought aluminium all for aircraft gas turbine compressor units. The skin material for Concorde is a specially developed clad sheet which meets the critical creep resistant requirements of the design.
The nominal percentage composition of RR58 is 2.5 copper, 1.5 magnesium, 1.0 iron, 1.2 nickel, 0.2 silicon, 0.1 titanium and the remainder aluminium. The sheet is clad with aluminium in which there is 1.0 per cent zirconium. The general distribution of materials in the airframe is shown in above. Hiduminium-RR58 is used for the majority of the structure, steel for sections subjected to higher temperatures and the highest loads and resin bonded glass fibre for the extreme nose section, where the skin temperature is highest.
RR58 is used in several different forms: sheet and strip (clad and unclad), plate, extruded sections, forgings and various bar sections. The clad sheet is used for the great majority of the fuselage skin and the outer skin of the engine intakes. The engine bay has an Inconel centre wall with aluminium alloy. The nozzle bay, aft of the rear spar, is of welded Stresskin sandwich panels and heat-resistant nickel forward doors and titanium rear doors alloys
Machined plate is used for the wings and fin surfaces. These plates are machined to form panels of various shapes which incorporate stiffeners and a similar form of construction is used for all the cabin window surround panels. The majority of the internal structural members of the fuselage and wings are RR58 which is used also for most of the riveting except in critical areas, where Monel rivets are used.
The steel is used for the entire structure of the elevons and rudders and the majority of the central sections of the engine nacelles, where structural loads are high, in machined member and honeycomb sandwich form (stainless); Air intakes are of RR.58 or AU2GN aluminium alloy with steel leading-edges.
Because the Concorde moves faster than sound, the air pressure and friction (collision with air molecules) really heat up the plane. The temperature of the aircraft’s skin varies from 261 degrees Fahrenheit (127 degrees Celsius) at the nose to 196 F (91 C) at the tail. The walls of the cabin are warm to the touch. To help reflect and radiate this heat, the Concorde has a high-reflectivity white paint that is about twice as reflective as the white paint on other jets. The heat encountered by the Concorde causes the airframe to expand 7 inches (17.8 cm) in flight.