The Lilium Jet is a prototype German electric vertical take-off and landing (eVTOL) electrically powered airplane designed by Lilium GmbH. A seven-seat production version is planned.

History

Initial design studies included forward-folding wings, so that the aircraft could be piloted as a VTOL and recharge in only few hours from a standard 240 V electrical outlet. A first half-scale demonstrator, ''Falcon'', flew in 2015. The unmanned

first flight First Flight may refer to: * Maiden flight, the first flight of a new aircraft type * First Flight Airport, in North Carolina, United States * First Flight High School, in Kill Devil Hills, North Carolina * ''First Flight'' (sculpture), a sculp ...

of the two-seat ''Eagle'' full size

prototype A prototype is an early sample, model, or release of a product built to test a concept or process. It is a term used in a variety of contexts, including semantics, design, electronics, and Software prototyping, software programming. A prototype ...

was on 20 April 2017 at the Mindelheim-Mattsies

airfield An aerodrome, airfield, or airstrip is a location from which aircraft flight operations take place, regardless of whether they involve air cargo, passengers, or neither, and regardless of whether it is for public or private use. Aerodromes in ...

Bavaria Bavaria, officially the Free State of Bavaria, is a States of Germany, state in the southeast of Germany. With an area of , it is the list of German states by area, largest German state by land area, comprising approximately 1/5 of the total l ...

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

. Unmanned flight testing of the five-seat Lilium Jet took place at Oberpfaffenhofen airfield near Munich. It first flew in May 2019. By October 2019, after 100 flights, it could transition from vertical to horizontal flight, reaching over , but not yet fully horizontal. It managed 25° banked turns, high ascent/descent rates like in operations, hover turns and sideward translations. Electrical, fan and flap failures were mitigated by the electrical and flight control systems. The first prototype was destroyed by fire during maintenance on 27 February 2020. A second partially-constructed prototype was undamaged. A further unfinished prototype was abandoned, and work begun on a seven-seat version. On 18 July 2024 Saudia Group and Lilium N.V. signed a binding sales agreement for 50 Lilium Jets, with options for the purchase of 50 more. At the end of October 2024, Lilium GmbH has conceded insolvency. Lilium's situation was triggered by the denial of a guarantee for a 50 million-euro loan from the Kreditanstalt guaranteed by the State of Bavaria.

Design

The Lilium Jet uses multiple relatively small ducted propellers driven by electric motors to provide lift during take-off and landing, as well as

thrust Thrust is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction to be applied to that ...

during the cruise phase. Lilium says that it refers to the propulsion system as a "jet" because the propellers are enclosed in

nacelle A nacelle ( ) is a streamlined container for aircraft parts such as Aircraft engine, engines, fuel or equipment. When attached entirely outside the airframe, it is sometimes called a pod, in which case it is attached with a Hardpoint#Pylon, pylo ...

s. The production Lilium Jet is intended to accommodate six passengers and one pilot. It is powered by 36

electric motor An electric motor is a machine that converts electrical energy into mechanical energy. Most electric motors operate through the interaction between the motor's magnetic field and electric current in a electromagnetic coil, wire winding to gene ...

s, six on each of the two front canards and twelve on each rear wing. The motors are installed above twelve tiltable rear flaps. The drive-carrying flaps pivot downwards for vertical launch. At the transition to the horizontal position, forward thrust is generated. This is claimed to be significantly more economical than a conventional

rotorcraft A rotary-wing aircraft, rotorwing aircraft or rotorcraft is a heavier-than-air aircraft with rotor wing, rotary wings that spin around a vertical mast to generate lift (force), lift. Part 1 (Definitions and Abbreviations) of Subchapter A of Chapt ...

, however the propulsion configuration generates very high disc loading and power-delivery requirements significantly exceeding the leading competitive eVTOL designs. Lilium invested in Ionblox for its silicon-dominant

anode An anode usually is an electrode of a polarized electrical device through which conventional current enters the device. This contrasts with a cathode, which is usually an electrode of the device through which conventional current leaves the devic ...

battery technology, which it believes offers uniquely high

energy Energy () is the physical quantity, quantitative physical property, property that is transferred to a physical body, body or to a physical system, recognizable in the performance of Work (thermodynamics), work and in the form of heat and l ...

and power density (12C with 3.8 kW/kG at 50% charge and 3.0 kW/kG at 30%) needed for hover and take-off phases, even at low charge levels. The target range is . Its 36 electric ducted fans are powered by a lithium-ion battery; less than is required to cruise.

Specifications

Usage

The Lilium GmbH plans to found an

air taxi An air taxi is a small commercial aircraft that makes short flights on demand. History The concept of air taxis existed as early as the 1910s. This concept goes back as early as 1917 with Glenn Curtiss’ prototype, the auto-plane. Furthermor ...

service for urban air mobility and Advanced Air Mobility with the Lilium Jet. The company expects that pilots will be needed for around 10 years until autonomous flights can take over.

Award

In October 2019 the Lilium five-seater Jet received a Red Dot Award: Design Concept for “Best of the Best”.

References

{{Reflist

External links

Official website

Independent Website / eVTOL News
Proposed aircraft of Germany Canard aircraft Electric aircraft Urban air mobility EVTOL aircraft Aircraft first flown in 2017 Aircraft first flown in 2019