We see and hear a lot of comments about eVTOL aircraft that just aren’t true. So, we’re sharing our top 5 list of the most common misconceptions about eVTOLs.
Misconception # 5:
eVTOL’s are unsafe because they can’t auto-rotate like helicopters.
It’s true - eVTOL aircraft cannot autorotate. Autorotation is an emergency procedure that helicopters with large, heavy rotors can perform if they lose engine power. When engine power is lost, the helicopter starts to descend, and air moving upward through the rotor blades can be used to maintain rotation of the blades.
The rotor blades will still produce some lift, but only enough to maintain a fairly rapid descent - and the pilot has one shot at steering the aircraft to a safe landing area and perform a flare to slow the aircraft enough for a safe landing. It’s very difficult and requires enough altitude and/or airspeed to perform the maneuvers. If the engine fails while at low altitude and without enough airspeed, the result is often a fatal crash.
eVTOL aircraft, on the other hand, typically have multiple smaller and lighter rotor blades that don’t have enough inertia to continue rotating when de-powered, and often have fixed pitch propellers that can’t be adjusted like larger helicopter rotors. However, most eVTOL aircraft are designed with redundant electric motors and propellers. In our case, HEXA has 18 electric motors (which are highly reliable and have only one moving part) so multiple motors can fail without ever needing to execute an emergency maneuver in the first place.
Should the aircraft lose control for any reason, a ballistic parachute, similar to those used in light aircraft (as shown above), can be placed in the space between the propellers. HEXA’s parachute is designed to be effective even at altitudes as low as 8-12 meters (26 - 39 feet) above the ground and no airspeed. While there is no steering control while parachuting to the ground, the descent rate is slow enough (and the aircraft light enough) to limit injuries and damages to the pilot, and people and property on the ground.
HEXA's low-altitude parachute
When it comes to safety, we applaud a bit of skepticism! The public should be asking hard questions, and new technology ought to come under intense scrutiny. However, autorotation is dangerous and not always possible - we believe eVTOLs with multiple motor redundancy that also incorporate parachutes can be much safer than helicopters!