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Research dossier · General Reference

Jacobs R-830

285 hp radial aircraft engine

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionApr 8, 2026
Entity authorityQ3805823 ↗
Source-derived summary

The Jacobs R-830 or L-5 is a seven-cylinder, air-cooled, radial engine for aircraft manufactured in the United States by the Jacobs Aircraft Engine Company, beginning in 1935.

Design and development

The R-830 was effectively an enlargement of the R-755 with strengthened stressed parts. With a bore and stroke of 5.0 in × 5.5 in (140 mm × 127 mm) the displacement was 831 cu in (13.6 L), takeoff power was around 285 hp (212 kW). The engine features steel cylinders with aluminum-alloy cylinder heads.

Editorial summary

“Jacobs R-830” enters the record as 285 hp radial aircraft engine. Crown Archives preserves that source wording while asking what Jacobs, R-830 and radial can confirm, complicate or overturn.

Editorial reviewA practical starting point whose main value is the path it opens into stronger specialist and primary sources. The current lead gives the account dated anchors—1935—that can be checked directly. The selected authority fields contribute no independent date. Its strongest next move is a source search built around Jacobs, R-830 and radial.
Editorial analysis

Why this record matters

“Jacobs R-830” is worth following because a concise public description often conceals a longer documentary argument. Here, Jacobs, R-830 and radial provides the most credible route into that argument.

Evidence profile

The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Apr 8, 2026. The linked authority identifier is Q3805823. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1935.

Critical limits

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.

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  2. Expand the search: follow Jacobs R-830 primary sources, Jacobs R-830 archive and Jacobs research across catalogues and specialist indexes.
  3. Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.

Questions for further research

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Source & attribution

This entry incorporates text from “Jacobs R-830” 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.