The Experts below are selected from a list of 21 Experts worldwide ranked by ideXlab platform
J.a. Retchford - One of the best experts on this subject based on the ideXlab platform.
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Reinforcement of the F-111 wing pivot fitting with a boron/epoxy Doubler system—materials engineering aspects
Composites, 1993Co-Authors: Alan Baker, R.j. Chester, M.j. Davis, J.d. Roberts, J.a. RetchfordAbstract:Abstract Local regions in the D6ac steel F-111 wing pivot fitting suffer plastic deformation during the cold proof test employed to screen out flaws in the steel components of the airframe. This deformation produces residual stresses which can lead to a fatigue cracking problem in service. This paper describes materials engineering aspects of a programme undertaken at the Aeronautical Research Laboratory to develop an advanced fibre composite Doubler system aimed at reducing the strain in these regions during the cold proof test and also to reduce cyclic strain during subsequent operation of the aircraft. The Doubler system chosen is boron/epoxy (over 120 plies thick) bonded with a structural film adhesive. Aspects described include selection and characterization of composite and adhesive bonding system, Doubler fabrication and application technology and evaluation of a representative Doubler specimen. Use of the Doubler system has been demonstrated to reduce the strain in the critical regions by over 30%, confirming design predictions.
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The Development of a Boron/Epoxy Doubler System for the F111 Wing Pivot Fitting - Materials Engineering Aspects
1991Co-Authors: Alan Baker, R.j. Chester, M.j. Davis, J.a. Retchford, J.d. RobertsAbstract:Local regions in the D6AC steel F111 wing pivot fitting suffer plastic deformation during the cold proof test employed to screen out flaws in the steel components of the airframe. This deformation produces residual stresses which can lead to a fatigue cracking problem in service. This paper describes materials-engineering aspects of a program undertaken at ARL to develop an advanced fibre composite Doubler system aimed at reducing the strain in these regions during the cold proof test and also to reduce cyclic strain during subsequent operation of the aircraft. The Doubler system chosen is boron/epoxy (over 120 plies thick) bonded with a structural film adhesive. Aspects described include selection and characterisation of composite and adhesive bonding system, Doubler fabrication and application technology and evaluation of a representative Doubler specimen. Use of the Doubler system has been demonstrated to reduce the strain in the critical regions by over 30%, confirming design predictions.
J.d. Roberts - One of the best experts on this subject based on the ideXlab platform.
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Reinforcement of the F-111 wing pivot fitting with a boron/epoxy Doubler system—materials engineering aspects
Composites, 1993Co-Authors: Alan Baker, R.j. Chester, M.j. Davis, J.d. Roberts, J.a. RetchfordAbstract:Abstract Local regions in the D6ac steel F-111 wing pivot fitting suffer plastic deformation during the cold proof test employed to screen out flaws in the steel components of the airframe. This deformation produces residual stresses which can lead to a fatigue cracking problem in service. This paper describes materials engineering aspects of a programme undertaken at the Aeronautical Research Laboratory to develop an advanced fibre composite Doubler system aimed at reducing the strain in these regions during the cold proof test and also to reduce cyclic strain during subsequent operation of the aircraft. The Doubler system chosen is boron/epoxy (over 120 plies thick) bonded with a structural film adhesive. Aspects described include selection and characterization of composite and adhesive bonding system, Doubler fabrication and application technology and evaluation of a representative Doubler specimen. Use of the Doubler system has been demonstrated to reduce the strain in the critical regions by over 30%, confirming design predictions.
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The Development of a Boron/Epoxy Doubler System for the F111 Wing Pivot Fitting - Materials Engineering Aspects
1991Co-Authors: Alan Baker, R.j. Chester, M.j. Davis, J.a. Retchford, J.d. RobertsAbstract:Local regions in the D6AC steel F111 wing pivot fitting suffer plastic deformation during the cold proof test employed to screen out flaws in the steel components of the airframe. This deformation produces residual stresses which can lead to a fatigue cracking problem in service. This paper describes materials-engineering aspects of a program undertaken at ARL to develop an advanced fibre composite Doubler system aimed at reducing the strain in these regions during the cold proof test and also to reduce cyclic strain during subsequent operation of the aircraft. The Doubler system chosen is boron/epoxy (over 120 plies thick) bonded with a structural film adhesive. Aspects described include selection and characterisation of composite and adhesive bonding system, Doubler fabrication and application technology and evaluation of a representative Doubler specimen. Use of the Doubler system has been demonstrated to reduce the strain in the critical regions by over 30%, confirming design predictions.
Alan Baker - One of the best experts on this subject based on the ideXlab platform.
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Reinforcement of the F-111 wing pivot fitting with a boron/epoxy Doubler system—materials engineering aspects
Composites, 1993Co-Authors: Alan Baker, R.j. Chester, M.j. Davis, J.d. Roberts, J.a. RetchfordAbstract:Abstract Local regions in the D6ac steel F-111 wing pivot fitting suffer plastic deformation during the cold proof test employed to screen out flaws in the steel components of the airframe. This deformation produces residual stresses which can lead to a fatigue cracking problem in service. This paper describes materials engineering aspects of a programme undertaken at the Aeronautical Research Laboratory to develop an advanced fibre composite Doubler system aimed at reducing the strain in these regions during the cold proof test and also to reduce cyclic strain during subsequent operation of the aircraft. The Doubler system chosen is boron/epoxy (over 120 plies thick) bonded with a structural film adhesive. Aspects described include selection and characterization of composite and adhesive bonding system, Doubler fabrication and application technology and evaluation of a representative Doubler specimen. Use of the Doubler system has been demonstrated to reduce the strain in the critical regions by over 30%, confirming design predictions.
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The Development of a Boron/Epoxy Doubler System for the F111 Wing Pivot Fitting - Materials Engineering Aspects
1991Co-Authors: Alan Baker, R.j. Chester, M.j. Davis, J.a. Retchford, J.d. RobertsAbstract:Local regions in the D6AC steel F111 wing pivot fitting suffer plastic deformation during the cold proof test employed to screen out flaws in the steel components of the airframe. This deformation produces residual stresses which can lead to a fatigue cracking problem in service. This paper describes materials-engineering aspects of a program undertaken at ARL to develop an advanced fibre composite Doubler system aimed at reducing the strain in these regions during the cold proof test and also to reduce cyclic strain during subsequent operation of the aircraft. The Doubler system chosen is boron/epoxy (over 120 plies thick) bonded with a structural film adhesive. Aspects described include selection and characterisation of composite and adhesive bonding system, Doubler fabrication and application technology and evaluation of a representative Doubler specimen. Use of the Doubler system has been demonstrated to reduce the strain in the critical regions by over 30%, confirming design predictions.
Rhys Jones - One of the best experts on this subject based on the ideXlab platform.
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Repair of Multi-Site Damage
Advances in the Bonded Composite Repair of Metallic Aircraft Structure, 2007Co-Authors: Rhys Jones, Lorrie MolentAbstract:Publisher Summary This chapter presents the results of a fatigue test program, which also considers environmental and damage-tolerance aspects, conducted using specimens representative of wide-bodied commercial aircraft fuselage lap joints. The phenomenon of multi-site damage (MSD) in aircraft has been under examination by many in the aviation industry. This chapter investigates the feasibility of applying advanced bonding technology to commercial aviation structures containing MSD. The consequence of the undetected presence of MSD was dramatically illustrated through the in-flight failure of a fuselage lap joint on an Aloha Airlines B-737 aircraft on April 28, 1988. Essentially this failure occurred due to numerous small cracks along a fastener line linking together, causing the residual strength of the fuselage to be exceeded under pressurization. A test program was conducted to reproduce this type of failure, and an adhesively bonded boron/epoxy Doubler for use as a repair or preventative measure has been developed.
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Application of constitutive modelling and advanced repair technology to F111C aircraft
Composite Structures, 2004Co-Authors: Rhys Jones, Lorrie MolentAbstract:Abstract To overcome cracking in F111 aircraft in service with the RAAF it was necessary to: (1) Provide an alternate load path so as to partially by pass the critical region; and (2) Change the geometry of the local region, thereby reducing the K t . To achieve the first a boron epoxy Doubler (reinforcement) was developed. To meet the requirements for continued airworthiness it was necessary to determine the associated inspection intervals. To this end it was necessary to obtain the residual stress, after CPLT, and the stress “per g” both with and without Doubler and with various grind out configurations. Since during CPLT the critical region undergoes gross plastic yielding to obtain this information requires a detailed elastic–plastic analysis. However, classical techniques for modelling this cyclic behaviour have inherent difficulties in representing the response to large cyclic inelastic strain excursions. Indeed, the use of classical analysis techniques resulted in an inspection interval, for the modified structure, of under 500 h. This contrasts with service experience which has shown that there is little further cracking. Indeed, for modified aircraft there has been no further cracking since 1985. To overcome this shortcoming an advanced “unified constitutive” model was used.
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Design of an all boron/epoxy Doubler reinforcement for the F-111C wing pivot fitting: Structural aspects
Composite Structures, 2003Co-Authors: Loris Molent, R. J. Callinan, Rhys JonesAbstract:Abstract This paper presents an overview of the structural aspects of the design and development of a local reinforcement designed to lower the stresses in a region of the F-111C wing pivot fitting which is prone to cracking. The stress analysis, representative specimen testing, thermal analysis and aspects of the full-scale static testing of this design are summarized.
R.j. Chester - One of the best experts on this subject based on the ideXlab platform.
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Reinforcement of the F-111 wing pivot fitting with a boron/epoxy Doubler system—materials engineering aspects
Composites, 1993Co-Authors: Alan Baker, R.j. Chester, M.j. Davis, J.d. Roberts, J.a. RetchfordAbstract:Abstract Local regions in the D6ac steel F-111 wing pivot fitting suffer plastic deformation during the cold proof test employed to screen out flaws in the steel components of the airframe. This deformation produces residual stresses which can lead to a fatigue cracking problem in service. This paper describes materials engineering aspects of a programme undertaken at the Aeronautical Research Laboratory to develop an advanced fibre composite Doubler system aimed at reducing the strain in these regions during the cold proof test and also to reduce cyclic strain during subsequent operation of the aircraft. The Doubler system chosen is boron/epoxy (over 120 plies thick) bonded with a structural film adhesive. Aspects described include selection and characterization of composite and adhesive bonding system, Doubler fabrication and application technology and evaluation of a representative Doubler specimen. Use of the Doubler system has been demonstrated to reduce the strain in the critical regions by over 30%, confirming design predictions.
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The Development of a Boron/Epoxy Doubler System for the F111 Wing Pivot Fitting - Materials Engineering Aspects
1991Co-Authors: Alan Baker, R.j. Chester, M.j. Davis, J.a. Retchford, J.d. RobertsAbstract:Local regions in the D6AC steel F111 wing pivot fitting suffer plastic deformation during the cold proof test employed to screen out flaws in the steel components of the airframe. This deformation produces residual stresses which can lead to a fatigue cracking problem in service. This paper describes materials-engineering aspects of a program undertaken at ARL to develop an advanced fibre composite Doubler system aimed at reducing the strain in these regions during the cold proof test and also to reduce cyclic strain during subsequent operation of the aircraft. The Doubler system chosen is boron/epoxy (over 120 plies thick) bonded with a structural film adhesive. Aspects described include selection and characterisation of composite and adhesive bonding system, Doubler fabrication and application technology and evaluation of a representative Doubler specimen. Use of the Doubler system has been demonstrated to reduce the strain in the critical regions by over 30%, confirming design predictions.
