Transcend Air is to use Maglev Aero’s magnetic levitation HyperDrive propulsion system for its Vy 421 tilt-wing VTOL aircraft. Announcing the collaboration on February 29, the two Boston-based start-ups said they are engaged in numerical analysis and simulation of the technology and aim to produce a subscale demonstrator in early 2025.
Under the plan, four HyperDrive units would replace a quartet of electric motors installed horizontally in the Vy 421’s tailfin. The aircraft’s main power source will be a pair of GE Aviation’s 2,500-shp CT7-8 turboshafts that will drive the propellers, with all other systems running off electrical generators connected to these engines.
Last year, Transcend Air announced plans for the Vy 421 aircraft, saying that it will be around 25 percent larger than its earlier Vy 400 design. It noted that the new model will be aimed at civil and military applications and will be able to carry eight people or a cargo payload of 3,500 pounds on flights of just over 1,000 miles at speeds of up to 486 mph.
According to Maglev Aero, the HyperDrive system is based on an existing VTOL aircraft concept known as an annular lift fan. The technology has been employed for high-speed railways that use magnets to lift a train off the track and propel it forward. With no friction to slow it down, the train can glide along the track at higher speeds and more efficiently.
“We are excited to work with MagLev to explore how their tech can make our vehicle even quieter,” said Transcend Air co-founder and CEO Gregory Bruell. “The history of helicopters teaches us that the small propellers called ‘tail rotors’ generate most of the noise, and our own numerical studies back that up. Our tailfin array already addresses that issue, and MagLev’s tech should take it further.”
Magnetic Track Combines with Rotor Blades
With the HyperDrive, the magnetic “track” is an array of magnets in the circular duct that houses the rotor. The magnetic circle essentially functions as a guide rail for the rim to which the blades are attached. As the bladed rim “levitates” inside that circular duct, it can spin without mechanical friction.
Traditional electric rotors convert electricity into mechanical energy, producing torque around the rotor’s axis to spin a propeller. The HyperDrive instead uses electricity from the batteries to power electromagnetic propulsors in the outer rim, which use magnetic fields to control the spinning of the rotor.
“A key benefit of the MagLev HyperDrive design is replacing smaller shrouded fans, like those in helicopter tails and on eVTOLs, with a quieter, more responsive alternative,” said MagLev CEO Ian Randall. “Plus, our zero-friction MagLev technology eliminates the wear of moving parts, leading to higher reliability and safety, and a reduction in the vibrations that lead to airframe fatigue.”
According to Transcend, the HyperDrive units should be easily integrated with the Vy 421’s existing quad fan array in the tailfin, which has already been designed to accommodate electric motors and fixed-pitch propellers. The company indicated that it expects to stick to its current development timeline, which calls for the propulsion system to be integrated with a proof-of-concept, full-scale version of the Vy 421 in the third quarter of 2025.
Transcend, which has had some support from the U.S. Air Force under Afwerx research and development contracts, does not intend to manufacture the Vy 421 aircraft when the model reaches series production. In 2021, it reached an agreement for Kaman Aerospace to produce the aircraft at its facility in Jacksonville, Florida, tapping its expertise in helicopter manufacturing.
