Prof. Mark White
From Leadership Profile: Vertiflite September/October 2022
Prof. Mark White, Head, Division of Aerospace, University of Liverpool
Within the University of Liverpool School of Engineering, Professor Mark D. White oversees 10 Aerospace Division members who are investigating flight simulation, structures, computational fluid dynamics and other specialties. “We cover a broad range of themes within a relatively small team,” he acknowledged. “We encourage collaborations, both within groups and across interdisciplinary activities. There is a lot of autonomy for people to do what they find interesting and, more importantly, what they can find funding for.”
White’s own focus on flight simulation has earned collaborations with the National Research Council of Canada (NRC), BAE Systems, Leonardo Helicopters, and other government and industry sponsors, including the UK’s Defence Science and Technology Laboratory (Dstl). He explained, “I currently have funded research to examine the question of ‘how good is good enough’ for rotorcraft training and certification, including human-machine interface requirements for future rotorcraft. It is thinking about the metrics and measures needed to examine the simulation fidelity requirements for helicopter operations in turbulent environments, e.g., ships, wind turbines, eVTOL [electric vertical takeoff and landing aircraft] and urban scenarios, and for flight training. The research has developed a new simulation fidelity rating scale and metrics to quantify pilot workload.”
Liverpool has four fixed-base simulators and two motion-base simulators to support undergraduate teaching and the main research themes. “The larger motion-base device is our main research simulator,” noted White. “We have a range of different aircraft models — fixed-wing, rotary-wing, tiltrotor and eVTOL. The majority are developed in-house with varying levels of fidelity. Students will develop models as part of their research projects, whilst for other projects we have flight test data to help validate our models for research.”
Research objectives vary widely, said White, “The themes are using simulation to support training, certification and design. The question is, ‘How good is good enough?’ Rotorcraft development programs can take a long time. The research question that underpins future developments is: ‘What are the simulation fidelity requirements needed to produce models that are of sufficient quality and credibility that we can use them for certification, reducing costs and risks, improving designs and reducing time to market?’
“Simulators can be used more broadly,” White observed. “How do you develop training simulators for the eVTOL training and certification market? From a training perspective, fidelity requirements are well established in current simulator certification documents. However, aircraft certification might pose different questions about what’s required. With training simulators, you’re trying to match simulation to flight test and one could tune the model in a non-physical way so that as long as the response matches, that is acceptable. For design — handling qualities and flight control laws — you want confidence that the parameters are physically correct; or if there is a difference, can you quantify that. How uncertain is the modeling and what effect does that uncertainty have on using simulation for certification? Those are ongoing research themes.”
From early school days, Mark White recalled, “I had an interest in engineering because it was problem-solving, but I didn’t have that desire to go into aviation or engineering specifically. I had a real interest in maths and physics, so it became a natural progression to study engineering.” The path to the University of Liverpool was indirect. “Strangely enough, I grew up in Indiana. I was born in the UK, but my dad was awarded a Fulbright scholarship to study for a PhD at Purdue University, and I went to kindergarten in West Lafayette.” John White subsequently took a teaching job in New York before he returned to the UK with his wife and family. Mark White recalled, “I was always known in junior school as the kid with the American accent.”
The senior Dr. White set up a sports sciences lab in the UK. “I enjoyed seeing that, seeing elite cyclists and athletes, and being around some of the researchers and joining in the testing. I think that tweaked my interest in doing research — they seemed to be enjoying themselves.” Maria White took a job in the University of Liverpool that ultimately shaped her son’s education and career. “My mum worked within the Engineering Department at Liverpool, so my first exposure to the University and engineering was coming into the department and being spoiled by the secretaries.” The future professor applied to several schools, but “I had been exposed to the engineering environment, and Liverpool was the closest. I chose mechanical engineering because at a school level, mechanical was the more logical for someone interested in math and physics, and Liverpool at that time did not offer aerospace engineering.”
Upon graduation in 1989, the new engineer made another career choice. “I was offered a position with a motor company, another Master’s program and a PhD at Liverpool. I was interested in the challenges in studying for a PhD, and I was working with Professor Norman Jones, who was a world leader in the structural impact area. There was work going on in my first research group that was interesting and provided new challenges.”
Mark White received his doctorate in 1992. “My PhD was in structural impact — crashworthiness. There was a lot of work on automotive crashworthiness, materials testing and dynamic loading. The post-doctoral work moved into the area of glass and composite testing. I subsequently became involved in a project on the crashworthiness of commercial aircraft and that was my first real exposure to aerospace engineering, but still in the mechanical structures group.”
White joined the Flight Science and Technology (FS&T) group at Liverpool, headed by Gareth Padfield in 2000 and then moved into an academic role in 2012. “I was fortunate before I took on the pure academic role to support the activities for the head of the group on aerospace research. I got involved with flight trials at the NRC, working with test pilots in simulation trials at Liverpool, all really exciting opportunities you just don’t get anywhere else. That’s led to working on research into the aerodynamic design of ships, including the UK’s new aircraft carrier, and the rotorcraft certification by simulation projects.”
Teach and Test
Mark White first attended what was then the AHS Forum in Baltimore in 2004. “When I joined the FS&T research group in 2000, the head of the group, Gareth Padfield, had been a member of AHS for a long time and been a significant contributor. It was just a natural thing that I joined. He advised me to go down the simulator fidelity route; a rich avenue for research.” FS&T has been presenting research on simulation fidelity for more than 15 years. White observed, “Going to the VFS Forum is about meeting people and networking. Seeing all the work that goes on sparks off ideas and potential areas for collaborations. It is the leading rotorcraft conference — the kind of place you want to be going to.”
White is now serving as the chair of the Society’s 79th Annual Forum & Technology Display on May 16–18 in West Palm Beach, Florida.
He also still serves as the deputy chair of the VFS Modeling and Simulation Technical Committee, having served on the committee for over 10 years; he also helped set up the VFS UK Chapter a few years ago. White is also a member of the Royal Aeronautical Society’s flight simulation and rotorcraft specialist groups, the GARTEUR Rotorcraft Group of Responsables, and the UK Vertical Lift Network. His current research engages the NATO modeling and simulation research community looking at rotorcraft modeling and simulation fidelity requirements for training, certification and shipborne helicopter operations.
White became a Professor at the University of Liverpool School of Engineering in 2019 and currently teaches three sets of undergraduate aerospace engineering classes including a Masters-level course on handling qualities. His research on simulator fidelity continues with government and industry sponsors. Work with BAE Systems helped clear the F-35B short takeoff and vertical landing (STOVL) fighter for the Queen Elizabeth-class aircraft carrier. The quality of the work was acknowledged through two BAE Systems awards. More research is ongoing on the effect of ship design on helicopter launch and recovery operations, which is having a significant impact on new design practices.
In terms of simulation fidelity research, White noted, “The work that we’ve undertaken with the NRC’s Flight Research Laboratory using their fly-by-wire Bell 412 aircraft, funded primarily by the UK’s Engineering and Physical Sciences Research Council, is ongoing. We have developed a simulator fidelity rating scale with them to assess ‘how good is good enough.’ A workshop was held at Liverpool this summer to develop best practices in this area and how to expand use of the fidelity scale more broadly.”
Simulator research continues on pilot-vehicle interfaces with motion, tactile and aural cueing, and White reflected, “In terms of simulation technology, what’s been really good is the change of scene away from custom hardware developed by simulator companies towards that offered by the gaming industry who offer lower-cost, high-quality products. The whole virtual/augmented/mixed reality question has emerged relatively recently as well.” White continued, “There are opportunities within the current training and certification standards to use these devices with potentially significant cost savings. Does a ‘one-size-fits-all’ work for the standards in terms of fidelity requirements? The answer is, ‘Possibly not.’ Why not? Where’s the evidence? That’s what the simulation fidelity research is about.”