I don't know why one would need to cite that the C421 is the largest of Cessna's twin engine piston line. One can verify by looking at the wiki entries for the 337,310,320,303, and 340 (that's the whole list). Kitplane01 (talk) 19:31, 14 January 2018 (UTC)Reply

No that is fine, when I tagged it the text you had entered said it was the "most capable". That needed a cite to understand what that meant, fastest, more payload, etc. - Ahunt (talk) 20:14, 14 January 2018 (UTC)Reply

"See also" should include 421's main rivals: smaller cabin-class turboprops, edit

Though the 421 is a piston-engine airplane, its principal rivals are NOT piston aircraft, but [small turboprop planes]. This is because the 421 was specifically engineered and priced to compete with the 1960s turboprops -- on speed, range and payload -- rather than compete with far-less-capable comparable-size piston aircraft of the time. It still fills that role, in the used-aircraft market today. — Preceding unsigned comment added by Zxtxtxz (talkcontribs)

That should be described in the text (with refs), not in endless lists under "see also" where there is no context for these comparisons. - Ahunt (talk) 15:42, 29 December 2020 (UTC)Reply
Then, by all means, please DO so -- since you are determined to set the standards, without citing any independent WP precendent or guideline.
~ Zxtxtxz (talk) 15:50, 29 December 2020 (UTC)Reply
Alternatively the section should be deleted - it still has far, far, too many entries, even after deleting entirely non-comparable aircraft (King Air - significantly larger, PC-12 - single-engined, much, much later) - when aircraft articles have been proposed for FA, large FA sections have been condemned by the wider community.Nigel Ish (talk) 15:57, 29 December 2020 (UTC)Reply
I'm not clear on the term "FA" - are you referring to "Featured Articles"? In any case, the term "large" is pretty subjective, and a mere dozen planes or so is certainly consistent with the Wikipedia MOS:SEEALSO guidance -- which not only notes that "See also" entries "should be limited to a reasonable number," but also advises that it could be much more than a single column of links:
"Consider using Columns-list or Div col if the list is lengthy"
adding:
"The links in the "See also" section should be relevant, should reflect the links that would be present in a comprehensive article on the topic,..."
because:
"One purpose of "See also" links is to enable readers to explore tangentially related topics"
In the case of the King Air 90 (not "King Air" generally), which I had added to the See also list, the airplane is very much a direct competitor to the Cessna 421, which would have been apparent if you'd read any of the major aviation industry media articles I linked to in my explanatory statement, above. In fact, the 421 was specifically designed as the Cessna defense against the market-encroachment of the Beech King Air 90 -- which remains, today, the principal aircraft it competes with, on cost, performance, and payload. Though some later variants of the 90 have solidly outclassed the 421, the 421 remains a direct competitor to most of the King Air 90s ever built -- as well as the Piper Cheyenne I, and other small turboprops. It leaves nearly all other piston twins in the dust (and I'm not a fan of the 421, just an experienced aviation industry professional, analyst, reporter and historian).
~ Zxtxtxz (talk) 16:36, 29 December 2020 (UTC)Reply
It is not a matter of citing guidelines, it is that a long list of unexplained turboprops, including single-engined ones, are not going to make much sense to a reader without some explanation as to why these are relevant to the 421. It would be better to present this information, with context and refs in the article text.
You probably don't want to get into "credentialism" here on WP:AIR, as we are all have pretty thick resumes as career pilots, engineers, maintainers, aviation execs, test pilots, historians, etc. We try to stick to references to make arguments. - Ahunt (talk) 17:09, 29 December 2020 (UTC)Reply
As I did, very carefully and thoroughly, in my initial post. ~ Zxtxtxz (talk) 18:39, 29 December 2020 (UTC)Reply