Costs and Aircraft Applications of Thermoplastic Composites 141 The estimation of the tailplane costs assuming that the material and components are being produced in volume quantity is shown in Table 38.The cost of the optimized tallplane. which uses injection molded brackets adjacent to the rear spar in place of the filled honeycomb block,is based on the assumption that laminates are tape lald prior to forming.Westland believes that the cost effectiveness of using these materials lies in automation of the processes involved.The major disadvantage in current thermoplastic manufacturing is the two stage proccss of producing consolidated preform sheets followed by a forming operation,hence an automated process that leads to a net shape component would be much preferable. 7.2.2 Advanced Tactical Fighter (ATF)and B2 Stealth Bomber [158,251-253] Advanced thermoplastic composites are widely used in developmental military aircraft such as Lockheed's and Northrop's versions of the Advanced Tactical Fighter (ATF),and Northrop's B2 Stealth Bomber[251-253].The all composite B2 bomber measuring about 5.2 m high by 21 m long with a wing span of 52.4 m consists largely of carbon/polyimide and other advanced plastic composite structure that make it virtually undetectable by radar [251].The ribs for a wing section on the B-1B bomber as well as the ribs,stiffeners,skin and leading edge on the inboard flap of the Fairchild A-10 have been made of APC-2 by the film-stacking method [252.253].Film-stacking fabrication was jointly developed under the U.S.Air Force Thermoplastic Composite Development Program. Materials for the proposed USAF ATF must retain structural performance at temperature up to 176C [74].In order to meet the service criteria defined for the aircraft,a material with a Tg of at least 200 C is required [741.Boeing Military Airplane Company has prototyped an ATF wing with 60%Amoco's Torlon polyamideimide reinforced with carbon fibres.The carbon/PAI prepreg is produced by Fiberite/ICI [253].Avimid K is being considered for the thick section,large area ATF prototype wing skins by the Lockheed/Boeing/General Dynamics team [158]. 7.2.3 Wing of the U.S.Navy/McDonnell F/A-18 Fighter Aircraft [188] MeDonnell Aircraft Co.is conducting research and development work on thermosets, thermoplastics,titanium and aluminum-lithium manufacturing technologies with direct application to future military and commercial aircraft.Presently more effort is devoted to the development of advanced thermoplastic composites than thermoset composites. To demonstrate the evolving thermoplastic composites technology and to gain manufacturing experience with these materials.an upper and lower outer wing skin for both wings of a U.S.Navy/McDonnell F/A-18 fighter aircraft have been manufactured and will be installed and service tested.The left wing panels are composed of thermoplastic composite AS4/PEEK while the right wing panels are made of epoxy composite IM-7/8551-7E.ThisCosts and Aircraft Applications of Thermoplastic Composites 141 The estimation of the tailplane costs assuming that the material and components are being produced in volume quantity is shown in Table 38. The cost of the optimized tailplane, which uses injection molded brackets adjacent to the rear spar in place of the filled honeycomb block, is based on the assumption that laminates are tape laid prior to forming. Westland believes that the cost effectiveness of using these materials lies in automation of the processes involved. The major disadvantage in current thermoplastic manufacturing is the two stage process of producing consolidated preform sheets followed by a forming operation, hence an automated process that leads to a net shape component would be much preferable. 7.2.2 Advanced Tactical Fighter (ATF) and B2 Stealth Bomber [1!5S, 251- 2531 Advanced thermoplastic composites are widely used in developmental military aircraft such as Lockheed’s and Northrop’s versions of the Advanced Tactical Fighter (ATF). and Northrop’s B2 Stealth Bomber[25 1 - 2531. The all composite B2 bomber measuring about 5.2 m high by 21 m long with a wing span of 52.4 m consists largely of carbon/polyimide and other advanced plastic composite structure that make it virtually undetectable by radar [251]. The ribs for a wing section on the B-1B bomber as well as the ribs, stiffeners. skin and leading edge on the inboard flap of the Fairchild A- 10 have been made of APC-2 by the film-stacking method [252.253]. Film-stacking fabrication was jointly developed under the U.S. Air Force Thermoplastic Composite Development Program. Materials for the proposed USAF ATF must retain structural performance at temperature up to 176“ C [74]. In order to meet the service criteria defined for the aircraft, a material with a Tg of at least 200” C is required [74]. Boeing Military Airplane Company has prototyped an ATF wing with 60% Amoco’s Torlon polyamideimide reinforced with carbon fibres. The carbon/PAI prepreg is produced by Fiberite/ICI [253]. Avimid K is being considered for the thick section, large area ATF prototype wing skins by the Lockheed/Boeing/General Dynamics team [ 1581. 7.2.3 Wing of the U.S. Navy/McDonneK F/A-18 Fighter Aircraft 11881 McDonnell Aircraft Co. is conducting research and development work on thermosets, thermoplastics, titanium and aluminum-lithium manufacturing technologies with direct application to future military and commercial aircraft. Presently more effort is devoted to the development of advanced thermoplastic composites than thermoset composites. To demonstrate the evolving thermoplastic composites technology and to gain manufacturing experience with these materials, an upper and lower outer wing skin for both wings of a U.S. Navy/McDonnell F/A- 18 fighter aircraft have been manufactured and will be installed and service tested. The left wing panels are composed of thermoplastic composite AS4/PEEK while the right wing panels are made of epoxy composite IM-7/8551-7E. This