Avgas
aviation fuel

Avgas (aviation gasoline, also known as aviation spirit in British English) is an aviation fuel used in aircraft with spark-ignited internal combustion engines. Avgas is distinguished from conventional gasoline (petrol) used in motor vehicles, which is termed mogas (motor gasoline) in an aviation context. Unlike motor gasoline, which has been formulated without lead since the 1970s to allow the use of catalytic converters for pollution reduction, the most commonly used grades of avgas still contain tetraethyl lead, a toxic lead-containing additive used to aid in lubrication of the engine, increase octane rating, and prevent engine knocking (spark-knock). There are ongoing efforts to reduce or eliminate the use of lead in aviation gasoline.
Kerosene-based jet fuel is formulated to suit the requirements of turbine engines which have no octane requirement and operate over a much wider flight envelope than piston engines. Kerosene is also used by most diesel piston engines developed for aviation use, such as those by SMA Engines, Austro Engine, and Thielert.
Properties
The main petroleum component used in blending avgas is alkylate, which is a mixture of various isooctanes. Some refineries also use reformate. All grades of avgas that meet CAN 2–3, 25-M82 have a density of 6.01 pounds per US gallon (720 g/L) at 15 °C (59 °F). (6 lb/U.S. gal is commonly used in America for weight and balance computation.) Density increases to 6.41 pounds per US gallon (768 g/L) at −40 °C (−40 °F), and decreases by about 0.1% per 1 °C (1.8 °F) increase in temperature.
This brief starts where responsible research should: with the source description of “Avgas” as aviation fuel. Everything that follows is an evidence route, not borrowed authority.
Why this record matters
The subject matters to the general reference register because the source frames it as aviation fuel. Its deeper value depends on whether names, dates, institutions and citations support that framing.
Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Jun 25, 2026. The linked authority identifier is Q340142. None of the 0 selected statements returned an explicit reference.
A concise general-reference account can conceal disagreements about scope, terminology or the weight assigned to individual sources. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “Avgas”, its source revision and the description used here.
- Expand the search: follow Avgas primary sources, Avgas archive and Avgas research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Avgas”?
- Which cited source is closest to the event, object or claim?
- What terminology or title could unlock a more precise catalogue search?
Search terms from this dossier
This entry incorporates text from “Avgas” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.