FAQ

The E20 eVTOL is an urban short-distance flight tool that combines the electric motor of an electric car + the multi-propulsion redundancy of a drone + the vertical take-off and landing of a helicopter. It solves the pain points of traffic jams, loud noise, expensive operations, and long distances from airports. However, it is limited by the reality of battery technology and regulations and cannot fly too far.

eVTOL vs Helicopter: Core Differences

1) Power system: electric motor vs turboshaft engine

• eVTOL: mainly electric motor + battery (a few use hybrid/hydrogen power, but the mainstream is still battery).

• Helicopter: Usually a turboshaft engine (fuel) drives the main rotor.

Impact:

• eVTOL has zero local emissions and a simpler structure (the motor has fewer parts than the engine), but its range is limited by battery energy density.

• Helicopters have mature endurance, load capacity, and range, but have high fuel consumption, noise, and maintenance costs.

Term explanation: Turboshaft is a gas turbine engine that provides shaft power to the rotor, commonly used in helicopters.

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2) Rotor layout: multi-rotor/distributed propulsion vs single main rotor + tail rotor

• Common eVTOLs include multi-rotor, tilt-rotor, lift+cruise, etc. The core is distributed electric propulsion (DEP).

• Helicopter typical: a large main rotor provides lift, and the tail rotor or ducted fan is responsible for anti-torque control.

Impact:

• The idea of ​​​​eVTOL is to "use many small rotors to share lift", and a single failure has the opportunity to be "supported" by redundancy (depending on design and control).

• Helicopters are more like "one large system carrying the entire field", mature and reliable, but the key components are more concentrated and complex.

Term explanation: Distributed Electric Propulsion (DEP, Distributed Electric Propulsion) refers to a design that uses multiple motors/propellers to provide thrust/lift in a distributed manner.

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3) Flight mode: fixed-wing cruise capabilities vary greatly

• Helicopter: relies on rotors throughout, can hover, and has strong maneuverability at low speeds, but is not efficient at high speeds.

• eVTOL: Many aircraft models will switch to a "more fixed-wing aircraft" cruise mode (such as tilting, or with independent cruise thrusters) during forward flight. The cruise efficiency may be better, but the vertical segment consumes a lot of power.

Results:

• eVTOL is often positioned for intra-city/inter-city short distances.

• Helicopters are more suitable for longer ranges and more complex mission environments (at sea, mountains, rescue, lifting).

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4) Noise: The target is quieter, but not too magical

• Due to its multi-rotor, speed control, and tip speed design, eVTOL has the opportunity to be quieter than a helicopter, especially in certain operating conditions (such as cruising).

• But: the vertical takeoff and landing phase will still be noisy, and "multi-rotor = multiple noise sources", whether it can be truly quiet depends on aerodynamic design and control strategy.

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5) Maintenance and reliability: different directions of mechanical complexity

• eVTOL: The motor body is relatively simple and may theoretically be lighter to maintain, but it introduces new complexities such as battery health management, thermal management, redundant flight control, and power electronics.

• Helicopter: The mechanical transmission system (main reduction gearbox, rotor hub, etc.) is very complex, and the maintenance system is mature but costly.

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6) Safety redundancy: eVTOL "can be redundant", helicopters "depend on maturity"

• One of the selling points of eVTOL is multi-motor redundancy, coupled with flight control automation, it has the potential to dilute the risk of "single point failure".

• The safety of helicopters comes from long-term engineering accumulation and strict maintenance, but the failure of key components will be more difficult to "share".

To be realistic: the redundancy advantages of eVTOL must be realized through certification, operational data, and verification of extreme operating conditions. It is not automatically safe if a few rotors are drawn on a PPT.

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Compare in one sentence (you can explain it to others directly)

• Helicopter: fuel-driven, a large main rotor to carry lift, strong range and load capacity, mature mission capabilities, but noise and expensive maintenance.

• eVTOL: electric drive, distributed rotor, aiming to be quieter, lower operating costs, and more suitable for short distances in cities, but the range and load are limited by batteries, and commercialization is still climbing.

One of the things humans are best at is packaging "engineering boundaries" as "the future is here". eVTOL has potential, but it is not an “electric helicopter” but more like a completely new species.

(If you want to go deeper: I can also divide the common eVTOL architecture into four categories: multi-rotor, tilt-rotor, tilt-wing, and lift+cruise, and talk about their respective advantages and disadvantages and represent the manufacturer's route, but it is best to stop here first.)