Universal Hydrogen

aid: universal-hydrogen
name: Universal Hydrogen
description: 'Universal Hydrogen Co. was a Hawthorne, California hydrogen-aviation startup founded in 2020 by former Airbus
  CTO Paul Eremenko to decarbonize regional air travel. Rather than building a hydrogen pipeline network, it proposed a modular
  capsule model: lightweight hydrogen capsules loaded into aircraft with existing cargo handling equipment, paired with fuel-cell
  powertrain conversion kits for regional turboprops such as the ATR 72 and De Havilland Dash 8. In March 2023 it flew a converted
  Dash 8-300 testbed with one propeller driven by a hydrogen fuel cell. The company raised roughly $100 million from backers
  including GE Aviation, American Airlines, JetBlue Ventures, Airbus Ventures, Toyota Ventures and Mitsubishi. Unable to raise
  further equity or debt or to find a buyer, it ceased operations on 27 June 2024 and liquidated. It was a hardware and fuel-logistics
  business and never shipped a public API, SDK, developer portal or machine-readable specification; its domains no longer
  serve a site.'
url: https://raw.githubusercontent.com/api-evangelist/universal-hydrogen/refs/heads/main/apis.yml
x-type: company
x-source: harvest:secondary-market
x-tier: stub
x-tier-reason: harvest
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  probe_state: none
  source: []
  generated: '2026-11-06'
  method: derived
specificationVersion: '0.20'
x-status: defunct
x-status-detail: Ceased operations in 2024 after failing to raise further funding; hydrogen.aero no longer resolves. No Website
  registered on purpose.
created: '2026-09-02'
modified: '2026-09-02'
tags:
- Company
- Defunct
- Aviation
- Aerospace
- Hydrogen
- Clean Energy
- Fuel Cells
- Sustainability
- Decarbonization
- Hardware
- Logistics
tags_raw:
- Company
- Defunct
- Aviation
- Aerospace
- Hydrogen
- Clean Energy
- Fuel Cells
- Sustainability
- Decarbonization
- Hardware
- Logistics
apis: []
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: GitHubOrganization
  url: https://github.com/universal-hydrogen
  x-evidence: Verified 2026-09-02 via https://api.github.com/orgs/universal-hydrogen (HTTP 200) — org id 71728862, display
    name "Universal Hydrogen Co.", blog https://www.hydrogen.aero, email hello@hydrogen.aero, created 2020-09-22. public_repos
    is 0, so it publishes no code, specifications or SDKs.
x-enrichment:
  date: '2026-09-02'
  status: minimal
  artifacts_added: 1
  pass: local-v1
x-coverage:
  state: none
  reason: defunct
  detail: 'Universal Hydrogen Co. ran out of cash and shut down on 27 June 2024, and both of its web hosts are gone: hydrogen.aero
    and www.hydrogen.aero answer a bare HTTP 404 "Unknown site" page on the root and on every /.well-known/ and specification
    path despite the A record still resolving, while universalhydrogen.com has been re-pointed to a Sedo parking lander whose
    wildcard catch-all returns the same parking HTML with a 200 on /llms.txt and /api-docs and CHEQ bot-filter 440/441 codes
    elsewhere. Its real GitHub organization is still live but holds zero public repositories, api./docs./developers.hydrogen.aero
    do not resolve, and the Wayback archive of the domain contains no developer or specification path — the company was a
    hydrogen fuel-capsule and powertrain hardware business that never published an API.'
  evidence:
  - url: https://hydrogen.aero/
    status: 404
  - url: https://www.hydrogen.aero/
    status: 404
  - url: https://hydrogen.aero/openapi.json
    status: 404
  - url: https://hydrogen.aero/llms.txt
    status: 404
  - url: https://hydrogen.aero/.well-known/agent-card.json
    status: 404
  - url: https://hydrogen.aero/.well-known/agent.json
    status: 404
  - url: https://hydrogen.aero/.well-known/security.txt
    status: 404
  - url: https://universalhydrogen.com/
    status: 200
  - url: https://universalhydrogen.com/openapi.json
    status: 441
  - url: https://api.github.com/orgs/universal-hydrogen
    status: 200
  - url: https://registry.npmjs.org/universal-hydrogen
    status: 404
  checked: '2026-09-02'
x-notes:
  website_pointer_removed: 'The stub''s only pointer was type Website -> https://forgeglobal.com/universal-hydrogen_stock/,
    a Forge Global secondary-market listing page. That is a trading-venue page, not Universal Hydrogen''s web presence, and
    wiring it as Website credits the company with a live site it does not have (roadmap#56). Removed 2026-09-02. The company''s
    own hydrogen.aero returns 404 and universalhydrogen.com is a Sedo parking lander, so no Website pointer is emitted at
    all. The Forge URL itself could not be re-verified: it answered HTTP 403 with a Cloudflare "Just a moment..." interstitial
    to both a browser User-Agent probe and WebFetch, which is a bot challenge rather than proof the page is dead.'
  name_collision: Do not conflate with Hydrogen Platform (hydrogenplatform.com), an unrelated fintech that does publish a
    developer API. Searches for "Hydrogen API" surface that company, not this one.