Dr Stephen Lambert from McLaren Applied explains how record-breaking technology from motorsport can help eVTOLs to go the distance
There has long been a close correlation between the technical advances in the automotive and the aerospace industries.
As we move to greater electrification, the cross over between automotive and aerospace technologies is gathering pace. When Rolls-Royce conducted its world-record breaking flight on the Spirit of Innovation last year, it was with the involvement of many other technology innovators including McLaren, famous for its Formula One motor racing cars.
Non stop approach to battery management
Dr Stephen Lambert, Head of Electrification at McLaren Applied explains how Rolls-Royce and McLaren combined their technologies to beat the record. “What we realised quite quickly was there’s a synergy between how you do things in motorsport, and how you might want to do things in aerospace and aviation. And then that’s different from automotive. For example, in automotive, you will, if you have a problem, put your vehicle safely into a stop mode and pull over. That’s the aim. You can’t do that in aerospace, you can’t just stop things because then things tend to fall out of the ground, out of the sky into the ground.”
“We have a very similar approach in motorsport, which is where you don’t want to stop at all costs. If you stop, you’re out of the race. So you want to carry on racing for as long as possible. And what we found was that, particularly when it comes to the batteries and battery management systems, that ability to carry on regardless, even if you know if you’re in a car, you would say otherwise, well, let’s stop. That ability to carry on regardless for as long as possible was what was found to be useful.”
McLaren’s motorsport battery management system technology was put into place within Rolls Royce’s record-breaking electric flight bid. Dr Lambert added: “A lot of the automotive systems they were looking at have the tendency to turn the batteries off when there was an issue – mainly, of course, it wasn’t necessarily safe in an aerospace application.”
The motorsport specialist has developed a next generation Silicon Carbide 800V Inverter which is a credible option for aviation powertrains, promising a greater range and reducing overall vehicle weight. He explained how this will work for eVTOL programmes
“We’ve had almost 10 years of developing inverters in in motorsport, and in automotive and we’re bringing to market in automotive a market leading agent evolve silicon carbide invert, the differentiation for that in automotive is it’s smaller and lighter. But most importantly, it’s more efficient than anything out there at the moment.”
“Efficiency is going to become more important”
With a range of eVTOLs now in the development stage, Dr Lambert said efficiency will become the differentiator. “We’re starting to see the inverter become the key brains, the key component within that electric vehicle drive train. When we look at aerospace, which is probably following behind automotive by, let’s say, five to 10 years, something like that, and that’s not uncommon, what we think we’re going to see is that efficiency is going to become more important even quicker. Mass is a big, big issue in any sort of aerospace application. And again, the way to get mass down, the way to get these electrified aircraft into the skies, is to keep the mass down by making your drive, your powertrain, more efficient.”
For operators of the next generation eVTOL, recharging electric aircraft will fast become a key issue. Dr Lambert explained that ensuring aircraft were as efficient as possible would help make the case for electric air transportation. “If your powertrain loses less of the energy to heat, well, that’s less energy you have to carry about. And it means it’s easier to take off, easier to land, you can have a bigger payload, and it also means you can recharge it quicker. So where you have applications where there may need to be a quick turnaround of an aircraft, that higher efficiency means you can start recharging quicker as well, it just starts to make the use cases for electrified air transportation, a little bit more successful, a little bit more realistic.”