Aircraft Forensic Engineering

The Defence Science and specialists provide the ADF with an Primary capabilities Technology Organisation (DSTO) essential independent forensic capability for engineering and scientific analysis into Aircraft Forensic Engineering has, is the Australian Government’s the causes of accidents and major incidents, collectively, hundreds of years of experience lead agency charged with failures or deterioration of metallic and non- investigating the behaviour of specialised applying science and technology metallic structural components, engines, materials used in the aeronautical industry. to protect and defend Australia systems and equipment. This extends to These materials can exhibit deterioration aviation support equipment including and damage as a result of manufacture, and its national interests. DSTO aircraft and airfield ground support maintenance, or operational service. delivers expert, impartial advice equipment, aircraft common spares, and and innovative solutions for aeronautical life support equipment. Aircraft Forensic Engineering’s capabilities for investigating problems include: Defence and other elements of In addition, the capabilities within Aircraft national security. Forensic Engineering extend to providing • On-site accident and major incident support to non-aviation investigations investigation and laboratory support; Overview related to Land and Maritime Systems. • Structural integrity defect analysis; • Quantitative assessments of damage One of the most important aspects accumulation, including determination of underpinning the structural integrity and fatigue crack growth rate; economic operation of aircraft (fixed wing • Corrosion damage assessment; and rotary) is the need for a highly • Composite material fracture analysis; experienced and expert capability • Aircraft wiring and systems investigations; which can provide correct diagnoses • Determination of metallographic structure, of defects and failures in aircraft hardness, tensile properties, fatigue life components and systems. and fracture toughness; The DSTO’s Aircraft Forensic • Metallurgical examination and Engineering section is the centre investigation of engineering materials, of excellence in aircraft defect and processes and components; failure analysis for the Australian • Chemical investigations of contaminated Defence Force (ADF), and in support equipment; to other government-related agencies • Failure modes and effects analysis (FMEA) and industries. and oxygen hazards and fire risk analysis (OHFRA); Aircraft Forensic Engineering • Specialist scientific advice and is the largest group of scientific recommendations for corrective and and technical aircraft failure preventative actions; specialists in Australia. These • On-site problem solving and consultation. Helicopter rotor brake disc cracking.

Main pictures: (left) scanning electron microscopy provides detailed imaging and (right) non-destructive examination using radiography. Aircraft Forensic Engineering in practice

Among the areas of expertise developed by Aircraft Forensic Engineering are quantitative fractography, composite material fracture analysis, aircraft wiring and systems, and oxygen systems and components.

Quantitative fractography

Providing world expertise in this area, quantitative fractography involves ‘reading’ the microscopic markings on fracture surfaces and then relating these to the service history of the component – thereby determining the crack growth rate. In many cases this has led to the development of an inspection program that enables critical aircraft parts to continue in service. With information on rates of crack growth, the useful life of a cracked component may be extended for many more flight hours with significant economic benefit.

Composite material fracture analysis Lower turbine compressor. Aircraft landing gear folding strut cracking.

Composite materials are increasingly being used in the construction and maintenance of modern aircraft. The analysis of fractures Aircraft Forensic Engineering have • Dimensional metrology facility; in composite structures is essential for developed a capability that covers a the understanding and identification of wide range of aircraft oxygen system and • Advanced non-destructive inspection the mechanisms and causes of defects component investigations that include: facilities; and failures in these structures. With new oxygen hazards and fire risk analysis ADF acquisitions such as the C130J, full (OHFRA), failure modes and effects • Mechanical testing; composite Tiger and MRH Helicopters, analysis (FMEA), contaminant analysis; and future aircraft such as the Joint investigations of oxygen fires, and liquid dry • Facilities specialising in petroleum, oils Strike Fighter and UAVs, Aircraft Forensic breathing oxygen analysis. and lubricants, analytical chemistry and Engineering provides the ADF a unique and corrosion; essential capability to undertake complex Facilities and equipment failure investigations of defects and failures • Access to modern finite element, in composite aircraft structures. Aircraft Forensic Engineering’s world- computational fluid and impact dynamics class laboratories, equipment and related analyses; Aircraft wiring and systems facilities include: • Access to chemical instrumentation Maintaining reliable electrical wiring and • High-resolution digital photography; including fourier transform infrared systems on aircraft fleets is a major issue spectroscopy and chromatography-mass for fleet owners worldwide, particularly • Modern scanning electron microscopes and spectrometry. for ageing aircraft. Aircraft Forensic x-ray energy analysis systems; Engineering is the ADF’s lead scientific arm in the assessment and advice on ageing • Precision optical measuring equipment wiring issues, and has worked together with with surface profiling capability; Further information the ADF to provide key advice on managing aircraft wiring now and into the future. • Modern microscopes with precision Defence Science and Technology motorised stages and advanced colour Organisation Aircraft oxygen systems and components digital imaging systems – digitally 506 Lorimer Street linked to desktop computers with image Fishermans Bend, Victoria 3207 The safe design, development and operation enhancement and measuring programs; of aircraft oxygen systems and components, Tel: +61 3 9626 7532 requires special knowledge of materials, • Computer-enhanced digital quantitative Fax: +61 3 9626 7718 design, testing, manufacturing, operation imaging facility; Email: [email protected] and maintenance practices. Through experience, knowledge and training, DSC0374 Oct 2010 DSC0374

www.dsto.defence.gov.au