# Aircraft categories **URL:** \ **Category:** Factual Questions\ **Created:** [April 6, 2008, 6:38pm UTC](https://boards.straightdope.com/t/aircraft-categories/444200 "2008-04-06T18:38:32Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [April 6, 2008, 6:38pm UTC](https://boards.straightdope.com/t/aircraft-categories/444200/1 "2008-04-06T18:38:32Z")
When an aircraft exists as a civilian model and a military model for example, the OH-58 and UH-1B have the civilian counterparts Bell 206 and Bell 205, they can be registered as Experimental or Restricted but not Standard. Why not? ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [April 6, 2008, 6:46pm UTC](https://boards.straightdope.com/t/aircraft-categories/444200/2 "2008-04-06T18:46:33Z")
The military models are similar to, but not identical with, the civilian ones. The rules governing Type Certificates are very arcane & in many cases arbitrary. If the military model differs in one magic TC-critical feature, the only way it can be registered in Std category would be if the manufacturer ran the whole damn machine throught the TC compliance exercise. That’s a million bucks for something as simple as on OH-58. not gonna happen. ---
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [April 6, 2008, 6:50pm UTC](https://boards.straightdope.com/t/aircraft-categories/444200/3 "2008-04-06T18:50:53Z")
[QUOTE=LSLGuy] If the military model differs in one magic TC-critical feature… [/QUOTE] Interesting. You’d think with so many years of service such aircraft could be added based on experience with the type. What about a T-41 vs. C-172? EDIT: Never mind the last. I just looked at Wiki and they said the T-41 is an ‘off the shelf’ 172. (Bigger engine, I notice.) ---
**Author:** ![ElvisL1ves](https://avatars.discourse-cdn.com/v4/letter/e/5daacb/32.png) [@ElvisL1ves](https://boards.straightdope.com/u/ElvisL1ves)\ **Post date:** [April 6, 2008, 7:10pm UTC](https://boards.straightdope.com/t/aircraft-categories/444200/4 "2008-04-06T19:10:41Z")
If the military aircraft was certified and manufactured as one, i.e. not under the FAA type certificate, it can never be retroactively made Standard. The military will not let itself be subject to the FAA. so that is always the case that I know of.