Early Diagnosis: An Eye on Aircraft Health

The ethos behind vehicle health management systems is simple – the more an operator knows about the health of an aircraft, the more efficiently it can manage its aircraft operations. Yet the potential of this relatively youthful concept could have complex and much more far-reaching benefits for the aerospace industry.

Existing systems have typically tapped into the management of supply chains and maintenance operations, but as research continues to snowball, new technologies could be used to produce in-depth diagnostics and prognostics of the immediate health of an aircraft – effectively allowing an operator to know the precise condition of its fleet. The knock-on-effect of having such rich information available at the industry’s fingertips could enhance efficiencies, reduce costs and improve aircraft safety and reliability on a scale never before witnessed.

Cranfield IVHM centre

This prospect has already captured the industry’s imagination and, in 2008, Boeing went so far as to launch the world’s first centre dedicated to the research and development of integrated vehicle health management systems (IVHM) at the UK’s Cranfield University. With BAE Systems, Thales UK and Rolls-Royce onboard as core partners (each investing £1m over five years), and the UK Ministry of Defence (MoD) and Alstom as members (each investing £150,000 over five years), the centre focuses on developing tools and techniques for automatically diagnosing vehicle system and subsystem health.

The IVHM centre’s commercial director, Jim Angus, says he believes the site is a unique opportunity to build on the recent progress of vehicle health management systems in the aerospace sector.

“When it comes to vehicle health management systems, the main thrust has come from the aerospace sector, in particular from Rolls-Royce’s Total Care and Boeing’s Gold Care. These organisations aren’t just selling products anymore; they are endeavouring to sell products supported by a wide range of services for the end user. With Total Care, for instance, Rolls-Royce is offering long-term contracts that provide engines on the basis of availability and maintainability, ultimately helping airlines to minimise operating costs,” Angus says.

By capturing the integrated vehicle health management system market at such an early stage of development, the IVHM centre has been able to assemble a team of experts to focus on the requirements of its core partners.

As a postgraduate college, the centre is also bringing through new talent by involving PhD, MSD and doctorate students in key research activities.

“The centre is driven by the requirements of our core partners but the issues tend to be very similar in other sectors. This is essentially a pre-competitive area. It currently makes sense for the industry to research vehicle health management systems in a collaborative way as the last thing you want to do in the current economic climate is duplicate work. When companies all come together and work in a centre like this, the core research activities come at a much lower cost,” Angus says.

“As this is a relatively new field, there aren’t that many people with skills and expertise in this area, but we have built a strong team here at the university. We are also forming alliances with other research players worldwide, and have, for example, recently signed a memorandum of understanding with CALCE at the University of Maryland.”

The centre hopes to utilise this global network of expertise as part of its quest to develop next generation vehicle health management solutions, but as Angus is quick to point out, the concept must first address regulatory issues.

“Vehicle health management systems can minimise maintenance actions, improve aircraft readiness and extend product life extension, ultimately enhancing vehicle safety and reliability. The information it produces, however, is currently strictly separated from flight critical systems. Regulators do not want these systems used in a way that might affect the safety of the platforms, and for that reason they are kept entirely separate,” Angus says.

“The next stage is using the information from vehicle health management systems to accurately predict what is going to go wrong in complex assets. We need to be able to convince regulators that we can do this with without impacting safety, which may be a tough challenge within the civil aviation aerospace sector.”

RFID technology takes off

RFID specialist Savi also agrees that the industry faces a steep challenge in order to tap into the potential of prognostics and diagnostics. The company, which is part of Lockheed Martin, provides asset and shipment tracking solutions that leverage auto ID and automatic identification and data capture (AIDC) technology such as active RFID, passive RFID, UID, GPS, barcode and sensors.

In recent years, the company has experienced strong interest from the aerospace industry towards implementing passive RFID tags on critical components, kits and tools. This has helped operators and manufacturers improve efficiencies in material handling, particularly given the elaborate scale on which many supply chains now operate.

Yet, Savi’s president of corporate development and strategy, David Shannon, feels the impetus now lies with using RFID technology onboard aircraft. “From my perspective, the focus over the last few years has not been on using RFID on operating aircraft as that’s where you run into challenges with permissions to fly with radios, but there has been a lot of progress in implementing RFID technology within the support infrastructure in and around the aircraft,” he says.

“The emphasis has very much been on inventory management as opposed to prognostics and diagnostics but I think that is only a point of time observation. Savi is now focussing its assets on the latter – what we call the ‘smart assets story’. This involves using RFID or low-powered wireless sensors on critical operating components of the aircraft in order to facilitate prognostics and diagnostics during operations and the repair processes.”

Shannon says he believes this new development will have a huge impact on the asset intensive aerospace industry. Already the defence sector is in the early stages of developing aircraft with inbuilt sensors for prognostics and diagnostics, but RFID could be used to take that technology one step further.

“If we look at some of the more advanced airframes being introduced on the military side, such as on Lockheed Martin’s F-35 joint strike fighter programme, we can see attempts to build prognostics directly into the aircraft by implementing traditional wired sensors that tie straight into onboard computers. However, the introduction of low-powered sensors that use RFID would enable reports on the condition of the aircraft to continue even when the aircraft is shut down or being repaired,” Shannon says.

“This combination of RFID and low-powered sensors will most likely be introduced in the defence sector before becoming more cost effective and entering the commercial sector. The military sector has harder schedules to predict and control, so having equipment where you can rely on prognostics and take the aircraft out of service when you absolutely have to could be very important in that setting.”

Low-powered sensors that utilise RFID could also prove a good option for retrofitting existing early-generation aircraft that are not equipped with sensors. As opposed to attempting to connect heavy-wired sensors throughout the airframe, RFID sensors can offer a far easier way of introducing onboard sensors to these types of aircraft.

Be it through next-generation aircraft or via retrofits, Savi hopes that one day these sensors will be used to deliver accurate information on an aircraft’s health, potentially offering huge savings to the aerospace industry as a whole. With the industry already reaping the benefits of implementing RFID within the supply chain and manufacturing processes, the company very much sees this development as a natural progression – culminating in what it has labelled as “smart assets”.

“From a commercial perspective, I see this technology as one day maximising the return on invested capital assets. Essentially this comes down to servicing scheduled needs – be it with commercial or military aircraft – with fewer operating aircraft and fewer maintenance personnel,” Shannon says.

“We are trying to use the term ‘smart asset management’ to capture this notion of what will be enabled by low powered sensors and RFID technology – which is ultimately all about making the assets we are applying them to so smart they become an active participant in their own management.”