Aircraft Battle Damage Repair Research Articles

Research on Standardization of Aircraft Battle Damage Description

Rapid and accurate description of battle damage is the first step in aircraft battle damage repair (ABDR). The standardized description of damage information is the basis of the construction of aircraft battle damage data model. This paper studies and analyses the statistical description of battle damage in the view of definition, damage mode and cause classification of battle damage, so as to obtain the basis for standardized description of battle damage information.

Effect of surface roughness on ultrasonic inspection of electron beam melting ti‐6AL‐4V

Purpose Experimental research was conducted on the effects of surface roughness on ultrasonic non-destructive testing of electron beam melted (EBM) additively manufactured Ti-6Al-4V. Additive manufacturing (AM) is a developing technology with many potential benefits, but certain challenges posed by its use require further research before AM parts are viable for widespread use in the aviation industry. Possible applications of this new technology include aircraft battle damage repair (ABDR), small batch manufacturing to fill supply gaps and replacement for obsolete parts. This paper aims to assess the effectiveness of ultrasonic inspection in detecting manufactured flaws in EBM-manufactured Ti-6Al-4V. Additively manufactured EBM products have a high surface roughness in “as-manufactured” condition which is an artifact of the manufacturing process. The surface roughness is known to affect the results of ultrasonic inspections. Experimental data from this research demonstrate the ability of ultrasonic inspections to identify imbedded flaws as small as 0.51 mm at frequencies of 2.25, 5 and 10 MHz through a machined surface. Detection of flaws in higher surface roughness samples was increased at a frequency of 10 MHz opposed to both lower frequencies tested. Design/methodology/approach The approach is to incorporate ultrasonic waves to identify flaws in an additive manufactured specimen Findings A wave frequency of 10 MHz gave good results in finding flaws even with surface roughness present. Originality/value To the best of the authors’ knowledge, this was the first attempt that was able to identify small flaws using ultrasonic sound waves in which surface roughness was present.

Experimental and numerical analysis of aerodynamic effects of repair patches on damaged airfoils

This investigation assesses the change of aerodynamic characteristics of triangular and star-shaped damaged airfoils with repair patches. Both experimental and numerical methods to determine aerodynamic coefficients are used in this study. The test model is a NACA 641-412 airfoil full span, which is considered by using five schematics: Clean model, damaged model, upper repaired model, lower repaired model, and fully repaired model. Repair patches are chosen based on the Aircraft battle damage repair (ABDR) manuals. Various effects of repair schemes on triangular and star-shaped damages are quantitatively and qualitatively illustrated. A novel visualization method by paint and oil is used in wind tunnel tests to study the effects of repair patches on the damaged airfoil.

Numerical Investigation of Bonded Repair for TDS of Helicopter and Characterization of Kevlar/Epoxy Composite Patch

The tail drive shaft (TDS) of a helicopter is vital component which is responsible for its stability, is often prone to impact damage during combat and is damaged. Usually when the tail drive shaft is damaged, it is replaced during maintenance. But during the time of conflict, the replacement shaft may not always be available. Hence the damaged shaft is patched by a repair technique known as adhesively bonded repair technique or Aircraft Battle Damage Repair (ABDR) technique. In this study, finite element analysis is carried out on the undamaged, damaged, and the patched model of the tail drive shaft, which determines that the deformation, stress and strain in the patched model of the shaft is reduced .Thus, the adhesively bonded repair is an emergency technique that is used to regain the static strength shaft. Mechanical characterization of Kevlar/Epoxy composite material is carried out to choose the apt lay-up sequence for the patch by evaluating its mechanical properties.

대공포 피격에 의한 항공기 날개 손상에 관한 연구

Aircraft battle damage repair(ABDR) is emergency repair method for the damaged aircraft in battle field. The main purpose of the ABDR is to increase the readiness of fighter aircraft during wartime. While many studies have been conducted to develop ABDR method, few efforts have focused on evaluation of damage and determination of the size of hole caused by enemy's anti-aircraft artillery attack. The aim of this study is essentially to quantify damage of aircraft wing attacked by anti-aircraft artillery. The computer simulations was performed to accomplish this goal. A number of simulations have been carried out to compare size of damages under various attack conditions. In conclusion, it was revealed that the size of damage varied depending on the type and direction of cannonball. Furthermore, in this paper, the proper path sizes are suggested for different damage conditions.

Aspects of battle damage repair of helicopter structures

AbstractThis paper summarises recent research conducted at the Defence Science and Technology Organisation in the area of aircraft battle damage repair, covering aspects such as ballistic testing, ballistic damage prediction, non-destructive damage inspection, structure residual-strength assessment, repair materials and techniques, repair design approaches, repair implementation and demonstration. The research has been focused on military helicopter composite structures. This paper provides an overview of a wide range of research conducted and detailed information in selected areas. Considerations for future research directions are also briefly discussed.

F-15 기체 전투손상 수리설계 및 평가기법 사례연구

전투기가 임무수행중 기체에 발생할 수 있는 전투손상에 대처하기 위해 손상평가 및 수리설계, 구조건전성 평가방법 등 손상 후속절차를 연구하였다. 사례로서 F-15 ECS Bay에 발생한 전투손상에 대하여 ABDR(Aircraft Battle Damage Repair) 기술을 적용하여 손상평가 및 수리설계를 수행하고, 그 내용과 절차를 양식에 정리하였다. 또한, 정적강도 및 피로수명 계산과 같이 수리설계 구조의 구조건전성을 평가하여 비행안전 여부를 입증하고 영구수리 시점을 판단하였다. For the purpose of facing battle damage that a fighter is subject to in combat, following recovery procedures such as damage assessment, repair design and structural integrity evaluation are investigated. A sample study is presented on the battle damage of F-15 ECS bay, which is comprised of damage assessment and repair design based on ABDR(Aircraft Battle Damage Repair) skills and work procedure complying with AFTO(Air Force Technical Order) forms. Further, the flight safety of repaired structure is validated and the time the permanent repair should be done is estimated through the evaluation of structural integrity such as the calculation of static strength and fatigue life.

Infield composites repair techniques for combat aircraft: research and development perspective

Combat aircraft that are damaged and reside on the ground are completely ineffectual to air component commanders. Aircraft battle damage repair (ABDR) aims to rapidly restore these damaged aircraft to some level of combat capability. To be effective, the repairs must allow the aircraft to return to combat in time to affect the outcome of the battle. The Composite Group at Department of Materials, Queen Mary College, University of London, has worked on various aspects of the rapid repair concept for composite materials. In the present paper in particular, the vacuum infusion method is highlighted as an alternative reliable bonded infield repair approach for composite monolithic skins. The study identifies certain technical challenges that the repair technique must address to be viable. Results are presented from a novel toughening method developed by incorporating polyester and carbon veils at the infused bondline, while single scarf coupons as well as full scale testing data demonstrate the effectiveness of the vacuum infusion repair technology in accordance with the ABDR specifications.

Design of Emergency Aircraft Repairs Using Composite Patches

The increasing demand for fatigue life extension of both military and civilian aircraft has led to advances in repair technology for cracked metallic structures. Conventional structural repairs may significantly degrade the aircraft fatigue life and lower its aerodynamic performance. Adhesively bonded composite reinforcement is a new technology of great importance due to the remarkable advantages obtained, such as mechanical efficiency and repair time and cost reduction. In this article, bonded composite patch repairs were designed for quick application to aircraft under emergency conditions, such as aircraft battle damage repair (ABDR). A formulated method was developed, to be applied when damage has to be restored quickly, without restrictions to safety of flight. Different damage cases were investigated using finite-element analysis (FEA), taking into account specific parameters of the structure under repair. Based on the FEA results, a quick design procedure using composite patch repairs for the most frequent damage cases is proposed.

Repairing composite aircraft structures — RAF experience of peacetime and battle damage techniques

AbstractThe RAF has been undertaking peacetime repairs on composite rotor blades, fibreglass radomes and panels on a variety of combat aircraft types for many years. However, the Service's main experience in the repair of aircraft structures manufactured from carbon fibre composite (CFC) material has been related to the Harrier II. In any future conflict involving air power, battle damaged aircraft, including the Harrier II, will have to be repaired rapidly to meet operational requirements. The repair techniques used may have to differ from those undertaken in peacetime but they must still aim to restore the full static strength of the aircraft within the time constraints imposed by the operational situation. Therefore, aircraft battle damage repair (ABDR) is a carefully planned alternative to conventional repair techniques. This paper describes the main CFC structures of the Harrier II and outlines the variety of RAF peace and wartime structural repair procedures applied to the aircraft. Examples are provided of various simple and complex repairs. Greater emphasis on adhesively bonded repairs is called for if Harrier II experience is to aid in the logistic support of Eurofighter 2000 (EF2000) in peace and war.

Royal Air Force Engineering

AN opportunity to become acquainted with the engineering expertise available at RAF Stations and to study the degree of involvement in design and manufacture occurred recently when visiting Abingdon and Marham. An aircraft maintenance and storage depot, RAF Abingdon's prime activity centres around the Engineering Wing which undertakes major servicing on Jaguar and Hawk aircraft and more recently, Buccaneer as well, together with various long‐term modification programmes. Responsibility is taken for assessing complex aircraft repairs, the recovery, salvage and transportation of all RAF, Royal Navy and Army fixed wing aircraft and in addition, assisting when necessary, the Aeronautical Inspection Branch in the recovery of crashed civilian aircraft. Some specialist tasks are also carried out, such as aircraft weighing and support for the RAF's Inspectorate of Recruiting, as well as housing the Aircraft Battle Damage Repair School. Storage of Jaguar aircraft is also undertaken as well as some VC 10 work.

US Air Force aircraft battle damage repair (ABDR) program : Jon D. Hull. Proc. a. Reliab. Maintainab. Symp., 72 (1987)

US Air Force aircraft battle damage repair (ABDR) program : Jon D. Hull. Proc. a. Reliab. Maintainab. Symp., 72 (1987)

U.S. Naval Forces aircraft battle damage repair : J. J. Kennedy. Proc. a. Reliab. Maintainab. Symp., 75 (1987)

U.S. Naval Forces aircraft battle damage repair : J. J. Kennedy. Proc. a. Reliab. Maintainab. Symp., 75 (1987)