Inside the Lilium Jet: 30 ‘Electric Jets,’ Bold Battery Bets – and the Hard Lessons from a $1B eVTOL

• What it is: A seven-seat (six passengers + one pilot) electric VTOL aircraft using ducted electric vectored thrust (DEVT)—small ducted fans embedded in tilting wing flaps rather than open rotors. Final production design used 30 fans (reduced from 36 in 2022). Aviation International News
• Target performance: Cruise ~280 km/h (175 mph); 250+ km (155+ mi) range incl. reserves (claimed). A later 2024 update suggested ~96 nm initial single‑charge range for early aircraft. evtol.news
• Notable milestones: First five‑seat demonstrator flights (2019); prototype ground fire (2020); FAA G‑1 certification basis (June 2023); EASA Design Organization Approval (Nov 2023); Saudia firm order for 50 (+50 options) (July 2024). WIRED
• Battery strategy: High‑power silicon‑anode lithium‑ion cells via Ionblox; pilot production with Customcells; scale‑up with InoBat. Aerospace America
• Status (Sept 19, 2025): Lilium entered insolvency/self‑administration in Oct–Nov 2024, later ceased operations; asset sale/redistribution underway (AAMG bidding; Vaeridion acquiring the battery facility). Reuters

The in‑depth report

1) The architecture that made Lilium different

Most eVTOLs rely on open rotors. Lilium doubled down on ducted fans integrated into tilting flaps across a canard and main wing. The company argued this could control noise, cut drag in cruise, and enable fine‑grained thrust vectoring with few external moving parts. The aircraft also emphasized “simplicity by design”—no ailerons, no vertical stabilizer, fixed gear, fly‑by‑wire with directional stability via differential thrust. evtol.news

• 30 vs. 36 fans: Early iterations used 36 fans (12 canard, 24 wing). In 2022, the design shifted to 30 (larger diameter units), aiming to simplify, reduce weight/cost, and allow more acoustic damping. Aviation International News
• Performance logic: Lilium’s technical team has long maintained the jet spends ~90–95% of missions in wing‑borne flight, where ducted fans (with variable nozzle effects and boundary layer ingestion) can be optimized for cruise—even if hover is power‑hungry. evtol.news

2) What the numbers said

From Lilium’s published targets and VFS profiles, the 7‑seater aimed for ~175 mph cruise and ~155+ miles including reserves—regional hops rather than short intra‑city hops. In April 2023, the Phoenix demonstrator hit 136 kt (155 mph) in testing. “We’ve changed what was theory and expected performance, into known and validated performance,” chief test pilot Andy Strachan said after that milestone. evtol.news

A 2024 AIN report suggested initial production aircraft would start closer to ~96 nm single‑charge range, broadly consistent with Lilium’s staged approach (grow range as cells improve). Aviation International News

3) The battery bet: high power at low state of charge

The Lilium Jet’s hover + transition phases impose very high power at low state‑of‑charge—a tough requirement. Lilium’s answer: silicon‑dominant anode cells with high specific power even at low SOC, in partnership with Ionblox (cells), Customcells (pilot production/qualification), and InoBat (volume production in Slovakia). In 2023, co‑founder Daniel Wiegand framed the strategy bluntly: “this battery turns from risk into competitive advantage for us.” Aerospace America

4) Certification: an aggressive dual‑track

Lilium pursued concurrent EASA/FAA validation: the FAA G‑1 certification basis for powered‑lift (June 26, 2023) and EASA Design Organization Approval (Nov 27, 2023), which authorized Lilium to design and hold a type certificate under the SC‑VTOL framework. These were real—and rare—wins in a crowded field. lilium.com

5) Commercial traction (on paper) and timelines

In July 2024, national carrier Saudia converted an MoU into a firm order for 50 Lilium Jets, plus 50 options—then the largest airline commitment in eVTOL. Lilium and Saudia positioned the aircraft for Hajj/Umrah flows and event shuttle service. Around the same time, Lilium publicly reaffirmed 2026 for first deliveries, with CEO Klaus Roewe saying, “Lilium continues to make significant progress towards entry into service…” Reuters

6) The physics debate it couldn’t escape

Critiques centered on disc loading. Small ducted fans move less air area than big open rotors; to generate the same lift in hover, power and jet velocity rise, penalizing energy usage and noise. Lilium’s own 2021 technical paper acknowledged the ducted architecture’s disc loading is up to ~10× higher than some open‑prop designs—then argued the cruise benefits offset hover penalties over typical missions. Independent outlets and analysts kept pressing the range/noise trade‑offs. lilium.com

7) The fall: cash, cadence, and a brutal market

After promising milestones in 2023–24 (power‑on of the first full‑scale aircraft, Saudia order, facility build‑outs), liquidity dried up. In late October–November 2024, Lilium sought self‑administration/insolvency protection in Germany and extended restructuring to the U.S. Reuters summarized the industry mood as Lilium “succumbed to a cash crisis,” with consultant Brian Foley warning, “We are starting to see the weaker players fall by the side … there will be more to follow.” lilium.com

8) Where things stand now (Sept 19, 2025)

• The company ceased operations earlier this year; asset sales are progressing. On Sept 19, 2025, AIN reported AAMG is edging closer to buying Lilium’s eVTOL assets and IP, while Vaeridion is acquiring Lilium’s battery facility. Aviation International News
• Even in insolvency, the IP, test data, supplier base, and regulatory groundwork (EASA DOA + FAA G‑1) retain value for potential program continuation under new ownership. lilium.com

Expert voices (short quotes)

• Andy Strachan, Lilium chief test pilot, on the 2023 speed milestone: “We’ve changed what was theory and expected performance, into known and validated performance.” Vertical Mag
• Daniel Wiegand, Lilium co‑founder, on the battery plan: “this battery turns from risk into competitive advantage for us.” Aerospace America
• Klaus Roewe, CEO, on deliveries (July 2024): “Lilium continues to make significant progress towards entry into service…” SEC
• Brian Foley, aviation consultant, on sector shake‑out: “We are starting to see the weaker players fall by the side … there will be more to follow.” Reuters

What Lilium got right

1. A coherent technical narrative: Ducted fans integrated into flaps, boundary layer ingestion, variable nozzle effects, and acoustic liners gave Lilium a defensible thesis for low cruise drag and controllable noise. evtol.news
2. Serious certification progress: EASA DOA and FAA G‑1 made Lilium one of a very small club with meaningful dual‑track regulatory footing. lilium.com
3. Battery realism: Rather than chase only energy density, Lilium emphasized power at low SOC—the real bottleneck for eVTOL hover/landing. Partnering Ionblox/Customcells/InoBat reflected that. Aerospace America

What broke

1. Power‑hungry hover vs. investor patience: The high disc‑loading architecture shifted payoff to cruise, but cash burn happens long before scale. With funding cycles turning, Lilium ran out of time. New Atlas
2. Range expectations: Public targets (~155+ mi) clashed with near‑term range nearer ~96 nm in 2024 disclosures—reasonable for a first block, but hard to reconcile with premium service economics investors expected. evtol.news
3. Program knocks: A 2020 prototype fire forced test cadence resets; supplier validation and software hurdles pushed first crewed‑aircraft dates. In a zero‑revenue phase, each slip compounds financing risk. Aviation International News

Why this still matters

Even if the original company disappears, the Lilium Jet program leaves behind:

• A distinctive DEVT architecture with deep aero‑acoustic and control‑law work that could inform hybrid architectures (e.g., short‑running landings to cut peak power). Vertical Mag
• A battery playbook squarely aimed at power‑limited phases and low‑SOC performance, now crucial across AAM. Aerospace America
• Regulatory scaffolding (EASA DOA, FAA G‑1) that a buyer could leverage. lilium.com

If AAMG or another buyer restarts the program, expect scaled targets first (shorter routes, limited payloads), with longer‑range variants as cell tech and thermal management advance.

Timeline highlights (selected)

• May 2019: Five‑seat demonstrator flies (Munich area). WIRED
• Feb 2020: Prototype destroyed in ground‑maintenance fire. Aviation International News
• 2021: Lilium publishes technical paper acknowledging high disc loading; argues cruise benefits. lilium.com
• Mar–Jun 2022: Fan count reduced to 30; short‑running landing added to reduce energy spikes. Aviation International News
• Jun 2023: FAA G‑1 certification basis. lilium.com
• Nov 2023: EASA DOA. lilium.com
• Apr 2023: Demonstrator hits 136 kt; test pilot quotes milestone. Vertical Mag
• Jul 2024: Saudia firm order (50 + 50 options). Reuters
• Oct–Nov 2024: Self‑administration/insolvency; cash crisis widely reported. lilium.com
• Sept 19, 2025: AIN: bidders move to acquire assets/IP. Aviation International News

Further reading (sources)

• Design & technology: VFS Vertiflite explainer, Lilium tech blog excerpts. evtol.news
• Performance targets: VFS aircraft profile. evtol.news
• Certification: Lilium on EASA DOA; Lilium on FAA G‑1. lilium.com+1
• Program knocks & milestones: WIRED 2019; Vertical Mag 2023; AIN/FlightGlobal 2020 fire. WIRED
• Orders & customers: Reuters on Saudia firm order. Reuters
• Battery partners: Aerospace America (Ionblox); Lilium–Customcells; Lilium–InoBat. Aerospace America
• Insolvency & aftermath: Lilium’s self‑administration notice; Reuters analysis; AIN asset sale update (Sept 19, 2025). lilium.com

Bottom line: Lilium aimed high—ducted fans, premium cabin, regional missions—and achieved real certification progress. But hover power, range realism, and a brutal capital cycle caught up first. The Lilium Jet’s ideas aren’t dead; they’re likely to re‑appear under new owners—slimmer ambitions at first, growing with the battery curve.