Image: RAAF's C-130J-30 Hercules medium transport aircraft, courtesy of Defence Force Recruiting.
Sponsored editorial piece written by Robert Ogden, Defence Science and Technology Group for Defence Force Recruiting, Principal Partner of Engineers Australia, Victoria Division.
On the 10th December 2015 after six years of fatigue test cycling and successfully simulating in excess of two lifetimes of operational usage, the international collaborative C-130J-30 Hercules Wing Fatigue Test Program came to a sudden metal splitting conclusion.
Managed by Marshall Aerospace and Defence Group (MADG) in Cambridge, United Kingdom, with oversight by Royal Air Force and Royal Australian Air Force (RAAF) Engineers as well as Scientists from the Defence Science and Technology (DST) Group, the outcome represented a Herculean step towards establishing a Structural Life of Type (SLOT) for the C-130J-30 Hercules operating under RAAF representative flying conditions.
Sixteen years prior, the Australian Government purchased the C-130J-30 fleet as a replacement for the ageing C-130E model, which had been in service for over thirty years. As launch customer for this new generation tactical transport aircraft, this investment did not come without some level of risk. The significance of this issue and the critical importance of technical airworthiness subsequently led the RAAF to enter into a collaborative program with the Royal Air Force to undertake C-130J fatigue testing.
In taking advantage of the significant DST Group experience in performing structural fatigue tests, DST Group scientists were embedded within MADG for the duration of the program. These staff, complemented by the placement of RAAF Engineers, served to enhance and protect Australian interests in this complex and expensive program.
With the fatigue testing phase of the program now complete and the focus switching to structural teardown, inspection and subsequent test interpretation, there is much work to be done in translating test findings into a substantiated SLOT. However, it is clearly evident that the accumulation of two operational lifetimes and demonstration of residual strength proves a highly durable structure that should realise significant financial and capability based benefits for the Australian Defence Force.
Ultimately, the realisation of such outcomes will owe considerable debt to the world class aircraft structural integrity science, engineering oversight, and leadership provided by the RAAF and DST Group staff that have supported this international collaborative structural test program.
Looking to the future, a structural test program of this nature also provides a wealth of data and opportunity to push the boundaries regarding the science of aircraft structural integrity. Such opportunities will further serve to enhance Defence and industry capability in supporting airworthiness management of current and future Defence Force platforms.