Will Air Taxis Change Everything? – S8, Episode 75
NASA researchers Siena Whiteside and Jason Welstead explain how RAVEN is helping engineers test the aircraft technologies that could shape the future of short-distance air travel.
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In this episode, Host Rick Crandall talks with Siena Whiteside and Jason Welstead about electric vertical takeoff and landing aircraft, better known as eVTOLs, and NASA’s RAVEN research aircraft. From urban air taxis and rural medical access to noise, safety, batteries, and flight testing, Whiteside and Welstead offer a clear look at how NASA is helping researchers understand what this new form of aviation will need before it becomes part of daily life. This one is going to be cool!
What Is an eVTOL?
An eVTOL is an Electric Vertical Takeoff and Landing aircraft. In plain terms, it is an aircraft that can rise straight up like a helicopter, transition into forward flight like an airplane, and land vertically again.
That ability makes eVTOLs better for short trips where roads are crowded, bridges create bottlenecks, or geography makes travel longer than it looks on a map.
Meet RAVEN
RAVEN stands for Research Aircraft for eVTOL Enabling techNologies.
Siena Whiteside, the principal investigator for RAVEN, describes it as a research platform rather than a passenger aircraft. RAVEN is roughly a 1,300-pound aircraft, converted from a fixed-wing kit plane into an unmanned eVTOL testbed. It will be remotely operated, meaning no one will be onboard.
Because RAVEN is a research aircraft, engineers can test higher-risk ideas without putting a pilot or passenger in the cockpit. At the same time, it is large enough to teach researchers lessons that small radio-controlled aircraft cannot.
Will I Fly the Aircraft?
No, think of it more like getting on a train. A passenger would not drive one down the street, take off from a driveway, and land at an office. Instead, eVTOLs would likely operate from designated locations, perhaps near transit stations, airports, rooftops, or other transportation hubs.
Jason Welstead explains that this creates a “first and last mile” challenge. A passenger still has to get to the aircraft, fly the main part of the trip, and then reach the final destination. For eVTOLs to be useful, the time saved in the air has to outweigh the time spent getting to and from the takeoff and landing sites.
That makes these aircraft part of a larger transportation system, not a replacement for every car trip.
The Big Picture
NASA is not trying to build an airline or manufacture commercial air taxis. Its role is research.
RAVEN is being developed as part of a broader effort called Open eVTOL. The goal is to share as much aircraft data as possible with the research community, industry, and universities. NASA is working with Georgia Tech on the project, with the hope that RAVEN can help researchers better understand eVTOL design, flight controls, acoustics, and safety.
That open approach matters because eVTOL technology is still new. Many of the design questions are not settled. How many rotors should an aircraft have? How should it transition from hover to forward flight? How much noise will it make? How should electric power systems be integrated? What happens if one part of the propulsion system fails?
These are the kinds of questions RAVEN is built to explore.
What the Research Will Tell Us
Throughout the conversation, Whiteside and Welstead return to three major research targets: safety, noise, and performance.
Safety comes first. For the public to trust eVTOL aircraft, they will need to meet very high standards. Welstead points out that urban air mobility is not a brand-new idea. Helicopter-based city transport existed in earlier decades, but noise and safety concerns limited its future. If eVTOL aircraft are going to succeed, they need to be designed and tested with public confidence in mind.
Helicopters often produce a recognizable low-frequency thump. eVTOL aircraft may sound different because they use multiple electrically driven rotors, so the goal is not simply to make them quiet, but to make the sound less disruptive in real communities.
Performance is the third challenge. eVTOL aircraft must use energy carefully. Hovering and landing take a lot of power, especially when battery reserves are low, making power management and flight control important and difficult.
How RAVEN Flies
RAVEN uses six rotors. Some tilt between vertical and forward positions, while others provide lift during hover. In vertical flight, the props do the lifting, while in forward flight, the wing takes over much of that job.
The transition between those two modes is one of the most important parts of eVTOL research. The aircraft has to accelerate, tilt its rotors, manage lift, and remain stable. Coming back from forward flight into hover brings its own challenges, including airflow changes and turbulence around the wing.
Whiteside notes that RAVEN has 24 control effectors, meaning parts of the aircraft that can influence its motion. These include rotor speed, blade pitch, and traditional control surfaces like ailerons and elevators. Coordinating all of them is a complex engineering problem.
What Does the Future Look Like?
Welstead imagines regional mobility becoming part of everyday life, allowing families to reach nearby destinations in minutes instead of hours. Whiteside points to public service uses, such as helping doctors reach rural communities more efficiently.
RAVEN is not just a new aircraft shape, but rather a story about how aviation research can help communities, expand access, and prepare engineers for the next generation of flight.
Like many important aerospace projects, RAVEN is also a learning platform. It gives students, universities, NASA researchers, and industry partners a way to ask better questions before new aircraft become common in the skies.
Frequently Asked Questions
Will RAVEN carry passengers?
No, RAVEN is a research aircraft, not a passenger vehicle. It is built to collect data and test ideas that may help future passenger-carrying eVTOL aircraft.
How is an eVTOL different from a helicopter?
Both can take off vertically, but many eVTOLs use multiple electric propulsors instead of one main rotor. They are also designed to transition into wing-borne forward flight for greater efficiency.
How could advanced air mobility help rural communities?
It could improve access to healthcare, public services, and regional travel by reducing long drives between smaller communities and larger service centers.
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