![]() ![]() New eVTOL aircraft will be subject to a different FAA certification framework from conventional aircraft. “Safety will dictate the certification timeline, but we could see these aircraft in the skies by 2024 or 2025,” the FAA said in an emailed statement. Those plans hinge on getting approval from the Federal Aviation Administration, the regulatory body for civil aviation in the US. Several of the largest eVTOL startups have announced plans to enter commercial service in 2025. But that said, is this idea really as crazy as it sounds? Actually, yes, yes, it is.Beta’s approach is to go after electric flight “in an intensely pragmatic way, and in a way that doesn’t require three or four miracles to happen at once,” Clark says, referring to both the technical challenges that face next-generation electric aircraft and the regulatory barriers ahead for the industry. And that’s not even getting into the multi-trillion-dollar infrastructure spend that would be necessary for widespread adoption of the idea. But even the chief proponents of round runways give away the weakness of the idea when they admit the runways would have to be heated to prevent catastrophic runway contamination and computers would have to be used to route traffic of varying speeds to the runway to realize the efficiencies hoped for. More recently, aviation think tanks in the Netherlands and the UK have run computer simulations, which seemed to confirm some benefits. The Air Force tested the idea in the 1960s but quickly abandoned it for all the reasons stated and more. With any kind of proposal, there are two ways to approach testing the idea, virtually and physically. The ILS approach wouldn’t work at such an airport, though one could imagine having multiple straight-in approaches to different points along the circle, and WAAS-based approaches could be established for curved paths.Finally, and there are many more concerns than these, balked landings would be problematic, airplanes of different speeds would inescapably come into conflict on the runway, crosswinds would accompany every landing, at least at some point, and at some point you’d be landing downwind, too. It’s not undoable, but it’s harder than going straight, that’s for sure. If we want to turn, we need to do something to make that happen, either with the landing gear and brakes or aerodynamically, through control surfaces. But what about if it rained, or got icy, or if there was a mechanical issue on landing? An object in motion wants to go straight. Think you could pull it off? Yeah, me too. Just think about landing a small plane on a banked race track. Planes landing on a circular banked surface, given there was sufficient wing clearance over the surface, isn’t too hard an idea to accommodate. ![]() The physics and aerodynamics of it are concerning.And if you ever needed to expand operations, how would you do that? Plus, think of all the tunnels you’d have to build to get ground vehicular traffic into and back out of the terminal area. Can you imagine DFW scraping its seven runways and building a giant circular replacement? Even if the circular runway were able to do what its proponents claim it could, the increased capacity wouldn’t cover the rebuilding of an airport that’s larger than the island of Manhattan. If we’re talking about the financial feasibility of the idea, we could stop the conversation right here. The infrastructure would be enormously expensive to change. ![]()
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