ABOUT PROPULSIONWATCH
Independent technical intelligence on electric propulsion and advanced air mobility.

Technical analysis, not hype.

Editorial standards

PropulsionWatch provides independent technical intelligence on the technologies, companies, and systems shaping the future of electric flight. We analyze developments across Advanced Air Mobility (AAM), eVTOL aircraft, electric propulsion, powertrains, batteries, and aircraft performance, turning complex technical and industry information into accessible insights, comparisons, and technology benchmarking.

Everything published here is based on public information only — SEC and EASA/FAA filings, patents, and published reporting. Nothing here reflects proprietary knowledge or the views of any employer, and none of it is investment advice.

The AAM industry produces a constant stream of announcements, certification updates, technical claims, funding news, and partnerships. Finding that information isn't the hard part — understanding what it means is. PropulsionWatch focuses on the engineering and certification decisions underneath the headlines.

HOW WE WORK

Evidence standards and verification

PropulsionWatch separates regulator-issued facts, company-reported claims, independent evidence, analysis and unknowns. A flight demonstration, certification-stage milestone or announced service date is not treated as approval unless the relevant authority has issued that approval.

Read the full methodology →

Evidence classes

Regulator-issued — certificates, rules, accepted bases, official notices and regulator-published records.

Company-reported — manufacturer releases, filings, technical pages and investor materials. These are attributed rather than silently converted into regulator facts.

Independent source — credible technical, academic or industry reporting used where primary evidence is incomplete or to corroborate context.

PropulsionWatch analysis — interpretation of disclosed evidence, kept separate from the underlying factual record.

Unknown — a field stays unknown when reliable public evidence does not support a value.

Certification language

Type Certificate, Production Certificate, individual Airworthiness Certificate and operator approvals are separate gates. Applications, certification-basis milestones, conformity work, test authorizations, compliance demonstrations and pilot programs do not by themselves equal a Type Certificate.

When companies use different certification-stage frameworks, PropulsionWatch preserves the source framework instead of implying false equivalence.

Targets and dates

Company schedules are labelled company targets. A date is described as regulator-committed only when regulator evidence supports that description. Historical dates are not carried forward after a re-baseline, restructuring or material program change without new evidence.

Published means the verified original publication date when known. Last reviewed or Last verified means a substantive evidence check, not a styling edit or site republish.

Program states

Lifecycle and operating-state labels describe observable program state, not a prediction. Development, flight test, certification, production, operational readiness and entry into service are kept separate. Demonstration service is not automatically treated as repeatable commercial operation.

Sources and change history

Material program and certification claims resolve to reusable source records. Program milestones preserve the event, date precision, authority, evidence class and whether an older milestone has been superseded.

Where sources materially disagree, the record remains in review or conflicting-evidence state rather than forcing a false single answer.

Corrections

Material factual corrections update the affected entity, its evidence record and any dependent tracker or article. Substantive revisions receive a new editorial review date; typo-only or styling changes do not.

Readers can email info@propulsionwatch.com to flag a source, terminology issue or factual discrepancy for review.

Core data definitions

Certification basis — the agreed or applicable airworthiness requirements against which compliance is demonstrated.

Type Certificate — approval of an aircraft type design by the relevant authority; it is not the same as production or operating approval.

Production approval — authority approval associated with producing conforming aircraft or products under an approved production system.

Entry into service — the point at which an approved aircraft begins the intended operational service; announcements or demonstrations alone do not establish EIS.

PRE-EIS — a program that has not yet reached the intended repeatable in-service operating state.

Last verified — the date the underlying evidence was substantively checked.