Image Credit: Jaunt Air Mobility
For some time, we’ve seen countless concepts of what an eVTOL air taxi may look like but this is not what you’d typically expect. Introducing Jaunt Air Mobility’s Reduced Rotor Operating Speed Aircraft, or ROSA for short.
This particular eVTOL air taxi seems to combine a helicopter and small aeroplane but it does seem to be the real deal. If you consider that safety and certification are the biggest obstacles the flying car market has to face, this eVTOL air taxi seems to be on the right track, or is it?
What’s Special About The Jaunt ROSA eVTOL Air Taxi?
Jaunt Air Mobility is one of many companies working on flying taxis but this design seems to be the safest. Better yet, it doesn’t need special certification which is a massive advantage in this emerging market.
With astronomical development and certification costs, Jaunt’s eVTOL air taxi may be significantly cheaper to get off the ground. While there is no official price, the funds necessary to certify a transitioning multi-mode aircraft is rather hefty. Rumour has it that the cost could be around half-a-billion dollars which is enough to put anyone off.
Besides the exorbitant initial costs, it also adds considerable price pressure on these services when they are ready for launch. Any company will find it difficult to deliver competitive per-mile prices with such a massive investment weighing on their shoulders.
Designing The ROSA eVTOL Air Taxi
This eVTOL air taxi is based on the CarterCopter design from 2004 with Jaunt having acquired all rights to the Carter Aviation Slow Rotor Compound. Carter’s 4-seat Personal Air Vehicle demonstrator aircraft completed more than 1,000 take-offs and landings with 100 hours of flight testing under its belt. At the time, it reached speeds up to 214 mph (344 km/h) and an altitude of up to 18,000 ft.
The ROSA uses it’s large, slow, powered top rotor to perform vertical take-offs and landings while four large electric props along the wing nullify the needs for a tail rotor. These electric props keep the aircraft from going into a tailspin while hovering while providing forward thrust to reach cruising speed. As soon as it builds up speed, the top rotor becomes completely unloaded which reduces drag. This results in high-efficiency flight as the wings take over lift generation.
The slow top rotor makes the ROSA much quieter, especially in cruise flight as the rotor can spin so slowly that you can barely see it. Considering the noise factor, Jaunt’s air taxi will have noise levels 50-66% lower than a regular helicopter or fixed-wing aeroplane.
Another key benefit is that the top rotor doesn’t use any of the bearings or pitch links that a helicopter does which means requiring less regular maintenance. It should allow for much longer periods between inspections compared to a fixed-wing plane which will further reduce operating costs down.
Even more impressive is its LevelFly technology as the top pylon housing the main rotor is designed to tilt. This allows the cabin to easily be balanced regardless of how many passengers are on board or their seating positions. It also keeps things more comfortable when transitioning between VTOL and winged flight.
How Safe Is It Really?
Jaunt’s ROSA gyrodyne with top rotors and big wings may not look as sleek as some of the other eVTOL designs but it appears to be the safest. One of the standout features is that it can make a safe landing using autorotation, similar to a helicopter. In an event of total power loss, the top rotor will still provide enough lift to bring the aircraft down gently and safely. The operator will have enough control to land regardless of altitude or airspeed which is a massive advantage.
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Certification In The US
In terms of certification, the ROSA fits into an existing category known as a “gyrodyne” and that means it can be certified under FAA Part 29 rotorcraft requirements. While there hasn’t been a gyrodyne certified in the US for decades, everyone understands Part 29 regulations from aviation engineers to the regulators. Jaunt plans to design an aircraft that is particularly easy to certify which will radically lower the cost of getting their eVTOL air taxi into full-scale commercial production and use.
While impressive in almost every way, there are still some unknowns. This includes the kind of range and recharge Jaunt can expect from a battery-electric powertrain. Considering the certification is expected by 2023, followed by production and commercialisation around 2025, there is enough time for battery developments that could make a significant difference in air taxis.
Current battery technology in terms of density and slow charging rates will be an obstacle facing every eVTOL start-up. The only exception is Alakai Skai as they’ll be able to deliver longer range and faster refills once they figure out how to supply its fleet with liquid hydrogen.
As it stands, Jaunt’s ROSA eVTOL Air Taxi looks to be one of the strongest in this segment. Here’s a look at Jaunt’s presentation at an Uber Elevate event.
The company is self-funded and have the means to get to the next level. As one of the partners chosen for the Uber Elevate program, Jaunt has partnered with BAE Systems, Triumph Aerospace Structures and Honeywell among others to turn this concept into a reality.
Unlike the Lilium, Joby, Skai, CityHawk, PAL-V, the ROSA is the width of a small plane but it doesn’t need special certification. By using advanced technology and innovative engineering, they’ve managed to reduce certification and operating costs while making it safer to use.
What do you think of the ROSA eVTOL Air Taxi? Is it good enough to be a personalised flying car or more along the lines of a commercial transportation network?
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