NASA RAVEN (concept design)

RAVEN (concept design)
NASA
Washington, D.C., USA
www.nasa.gov

Established in 1958, the National Aeronautics and Space Administration (NASA) is an independent agency of the U.S. federal government responsible for the civil space program, aeronautics research and space research. NASA is headquartered in Washington, D.C. and has 10 major field centers. NASA has made space ships, explored space, the moon, launched satellites, gathered data about Earth from space, made the Skylab Space Station, explored Mars, studied our solar system using space probes and more. (Image credit: NASA)

NASA started researching distributed electric propulsion (DEP) electric vertical takeoff and landing (eVTOL) and hybrid-electric VTOL aircraft in 2009. DEP was introduced to the world in November 2009 when Mark Moore, while still at NASA, unveiled the Puffin, a personal an all-battery eVTOL concept design aircraft. For the first time, the world caught a glimpse at how electric propulsion might transform everyday flight. In 2010, according to one website, the first eVTOL aircraft flown was NASA's Puffin subscale eVTOL tailsitting aircraft.

In 2014, NASA built both eVTOL and fixed-wing DEP technology demonstrator aircraft. Some of the key design features for NASA's advanced air mobility (AAM) common reference vehicles is to increase safety exponentially, reduce the complexity of the aircraft, decrease the cost of manufacturing, minimize maintenance costs, lower the final ticket cost to the consumer, lessen or have no carbon footprint for the aircraft and decrease the noise level for the general public.

NASA has continued making passenger eVTOL concept designs, technology demonstrators and research eVTOL aircraft for any company that wants to take advantage of NASA's research. In addition, NASA is now making eVTOL and hybrid-electric eVTOL aircraft to explore planets and their moons, in our solar system. As of 2024, NASA's space probes have not traveled to any other solar systems in the Milky Way galaxy, yet.

Mark Moore, Co-Founder and CEO of Whisper Aero (formerly a Principal Investigator and Chief Technologist for On-Demand Mobility, NASA and Engineering Director of Aviation, Uber Elevate) at the Vertical Flight Society's 7th Annual Electric VTOL Symposium, Jan. 21-23, 2020 in San Jose, California, USA, stated concerning advanced air mobility (AAM), "There has not been this pace in aeronautics since the Wright Brothers."

NASA RAVEN uncrewed eVTOL open-source technology demonstrator concept design
The NASA RAVEN is an uncrewed eVTOL concept design aircraft that will eventually be manufactured into an open-source technology demonstrator. The RAVEN research aircraft will enable researchers and industry partners to obtain and publish unique flight test data at a relevant scale, provide a platform to develop practical methods for AAM vehicle design, operations and train the next generation of aerospace engineers. All information from the research aircraft will be publicly available and the aircraft is expected to be used for many years. The aircraft will also be known as a flying laboratory. The acronym of the aircraft stands for Research Aircraft for eVTOL Enabling TechNologies (RAVEN).

The above illustration is what the RAVEN uncrewed eVTOL technology demonstrator aircraft is expected to look like. NASA is collaborating with Georgia Tech (Atlanta, Georgia, USA) to design and build the RAVEN flying laboratory. The plan is to offer "fast to flight" for research at a modest cost by using off-the-shelf components and airframe.

The general specifications of the aircraft, such as cruise speed, flight time, cruise altitude are unknown as this is a research aircraft that has not flown yet. The empty weight of the aircraft has been estimated to be 1,000 lb (454 kg). The aircraft's passenger compartment has the ability to carry additional payloads, such as avionics, sensors, flight computers and more. As stated before, there are no plans for the flying laboratory aircraft to carry any pilots or passengers.

The aircraft will have one high main wing and one conventional rear tail, with one vertical stabilizer and a horizontal stabilizer. The aircraft has six propellers, six electric motors and will be powered only by batteries. There are four tilt-propellers on the aircraft and two stationary VTOL-only propellers. Two of the tilt-propellers are mounted on the wing tips. There are two booms mounted under the high main wing about one-third of the distance from the fuselage and have tilt-propellers at the front of these booms. In the rear of the booms are where the two stationary VTOL-only propellers are located. The aircraft has fixed tricycle wheeled landing gear.

NASA advanced air mobility (AAM) aircraft research areas:

• Aircraft Design
• Noise and Annoyance
• Operational Effectiveness
• Performance
• Propulsion Efficiency
• Rotor-Rotor Interactions
• Rotor-Wing Interactions
• Safety and Airworthiness
• Structure and Aeroelasticity

NASA's advanced air mobility (AAM) facilities and capabilities include:

• Air Traffic Operations Lab
• Airspace Operations Lab
• Ames UAM Lab
• CERTAIN Range
• Cockpit Motion Facility
• Cognitive Engineering Lab
• Computational Fluid Dynamics
• Developmental UAM Simulator - Flyer
• Dryden Aeronautical Test Range
• Exterior Effects Room
• Flight Loads Lab
• Future Flight Central
• Icing Research
• Landing and Impact Research Facility
• Low Speed Aeroacoustic Wind Tunnel
• Mobile Acoustics Facility
• Mobile Operations Facility
• Research Flight Deck
• Testbed Virtual Infrastructure
• UAS Flight Test Control Room
• Vertical Motion Simulator
• X-57 Maxwell
• 12' Tunnel-Low-Cost Exploratory Facility
• 14 by 22 Foot Subsonic Tunnel

In February 2023, NASA published an article title, "NASA is Creating an Advanced Air Mobility Playbook." NASA is working with academia, government agencies, industry, cities and tribal nations to make advanced air mobility (AAM) a reality. NASA's areas of support include accessibility, automation, cargo delivery, emergency response, future airspace, healthcare, infrastructure, noise, ride quality, safety, travel time, vertiports and more.

NASA RAVEN-SWFT subscale eVTOL prototype of the planned RAVEN Technology Demonstrator
As a side note, the NASA RAVEN-SWFT is a 28.625% subscale eVTOL prototype that is modeled after the planned RAVEN uncrewed eVTOL 1,000 lb (454 kg) Technology Demonstrator flying laboratory aircraft. SWFT stands for "Subscale Wind tunnel and Flight Test" aircraft. The full acronym decoded for this subscale prototype is Research Aircraft for eVTOL Enabling techNologies (RAVEN) Subscale Wind tunnel and Flight Test (SWFT) or RAVEN-SWFT.

NASA will use the RAVEN-SWFT prototype to research relevant challenges in flight dynamics, flight controls, aerodynamics, propulsion integration, acoustics, vehicle geometry and more, in both wind tunnel and real world flight test experiments. The subscale aircraft was built at NASA Langley Research Center (LaRC), located in Hampton, Virginia, USA. Multiple papers have already been published about the RAVEN-SWFT prototype and NASA plans to continue to release data, methods and guidance in future publications.

Specifications:

• Aircraft type: RAVEN uncrewed eVTOL technology demonstrator concept design aircraft
• Piloting: Remote piloting
• Capacity: No pilot, no passengers
• Cruise speed: Unknown
• Hover flight time (expected): 10 minutes with a 25% battery reserve
• Cruise altitude: Unknown
• Empty weight (estimated): 1,000 lb (454 kg)
• Propellers: 6 propellers (4 tilt-propellers and 2 VTOL-only stationary propellers). 2 tilt-propellers are mounted on wing tips. Two booms mounted under the high main wing, about 1/3 distance from the fuselage, have tilt-propellers at the front of the booms and stationary VTOL-only propellers on the rear of the booms.
• Electric motors: 6 propellers
• Power source: Batteries
• Fuselage: Carbon fiber composite
• Windows: Panoramic wrap around windows
• Wings: 1 main high wing
• Tail: 1 conventional tail, with 1 vertical stabilizer and 1 horizontal stabilizer
• Landing gear: Fixed tricycle wheeled landing gear
• Safety features: Distributed Electric Propulsion (DEP) means having multiple propellers (or electric ducted fans) and multiple electric motors on an aircraft so if one or more propellers (or electric ducted fans) or some electric motors fail, the other working propellers (or electric ducted fans) and electric motors can safely land the aircraft. DEP provides safety through redundancy for passengers or cargo. There are also redundancies of critical components in the sub-systems of the aircraft providing safety through redundancy. Having multiple redundant systems on any aircraft decreases having any single point of failure. In case of an emergency, the aircraft can land conventionally, with or without power, if there is a runway or unobstructed road available.

Related Aircraft:

• NASA Dragonfly (space probe)
• NASA Greased Lightning (defunct)
• NASA LA-8 eVTOL Testbed (prototype)
• NASA Lift+Cruise (concept design)
• NASA Multi-Tiltrotor (concept design)
• NASA Puffin (concept design)
• NASA Quadrotor (concept design)
• NASA Quiet Single Main Rotor (concept design)
• NASA Side-by-Side (concept design)
• NASA Tiltduct (concept design)
• NASA Tiltrotor (concept design)
• NASA Tiltwing (concept design)

Company Insights:

• Crunchbase
• Tracxn
• Wikipedia

Resources:

• NASA website
• NASA Research Aircraft for eVTOL Enabling techNologies (RAVEN) web page
• NASA Advanced Air Mobility Mission web page
• NASA Advanced Air Mobility Mission More News web page
• NASA Air Mobility Pathfinders(AMP) Project More News web page
• NASA Advanced Air Mobility STEM Learning Module web page
• NASA Aeronautics Research Institute web page
• NASA Air Mobility Pathfinders Project web page
• NASA Urban Air Mobility (UAM) Reference Vehicles web page
• NASA Facebook
• NASA Twitter
• NASA YouTube Channel
• NASA Instagram
• NASA LinkedIn
• Advanced Air Mobility Wikipedia
• Article: NASA Talk Looks at the Future of Electric Propulsion in Aviation, PR News Wire, July 9, 2015
• Article: The eVTOL is in the Details, Vertiflite, March/April 2018
• Article: Lift+Cruise, a candidate research design for the UAM airspace, Research Gate, Jan. 2021
• Article: Building the Infrastructure for Advanced Air Mobility, NASA, July 18, 2022
• Article: NASA is Creating an Advanced Air Mobility Playbook, NASA, Feb. 2, 2023
• Article: NASA’s Autonomous Aircraft Decision Tech Gets Simulated Urban Test, NASA, Feb. 24, 2023
• Article: AFWERX, NASA collaborate to develop digital Advanced Air Mobility operations center, U.S. Air Force, Nov. 28, 2023
• Article: NASA Autonomous Flight Software Successfully Used in Air Taxi Stand-Ins, NASA, Jan. 25, 2024
• Article: NASA Noise Prediction Tool Supports Users in Air Taxi Industry, NASA, Apr. 4, 2024
• Article: NASA on Advanced Air Mobility Integration, Drone Life, Apr. 30, 2024
• Article: NASA Prepares for Air Taxi Passenger Comfort Studies, NASA, June 27, 2024