Talk:LR91

This Article Has the Wrong Name
There is no LR-91 and never was. The proper nomenclature is LR91. The designation system in use for jet and rocket engines excludes placing a hyphen between the letters describing the engine and the numbers indicating the serial acceptance of the engine.

Below is an document explaining the nomenclature in use since 1945:

"1. Representatives of the Navy Bureau of Aeronautics and of the Air Technical Services Command have agreed on the following general system of designating aircraft jet propulsion engines:

a. The system will be composed of two parts separated by a dash. The first part will consist of a letter(s) describing the general nature of the engine and a number designating the serial acceptance of the type. The second part shall consist of a number designating model under the basic type. The letters to be used in the first part of the designation are as follows with definitions as shown:

(1) J – Jet engine (without propeller)

T – Jet Engine (with propeller)

R – Rocket

PJ – Intermittent Jet Engine (Example: Buzz Bomb Engine)

RJ – Ram Jet engine

b. The odd numbers for the first and second parts of the designations will be used by the Army and the even numbers by the Navy. A particular engine will be identified by the same designation for both the AAF and the Bureau of Aeronautics. The number designating the engine type will begin with the number 30 in order to avoid confusion with some Navy airplane designations in which the new letters are used. Examples of this system are as follows:

(1) J31-1 – First Army model of first Army type of a jet engine (without propeller)

31-2 – First Navy model of first Army type of a jet engine (without propeller)

J31-3 – Second Army model of first Army type of a jet engine (without propeller)

J30-1 – First Army model of first Navy type of a jet engine (without propeller)"

The USAF "T.O. 21M-HGM25A-1-1 Technical Manual Operation and Organizational Maintenance HGM-25A Missile Weapon System" defines the second stage engine in paragraph 1-247 (page 1-103) as: "STAGE II ROCKET ENGINE. The Stage II rocket engine subassembly (figure 1-61), designated LR91-AJ-3, consists of a single thrust chamber assembly and an intigrated hot-gas vernier assembly.""

The designation means Liquid Rocket 91 AeroJet second USAF version. The first USAF version was the LR91-AJ-1, the third USAF version LR91-AJ-5 was used in the Titan II.

Any comments before I change the name to the proper one?

Mark Lincoln (talk) 17:26, 16 February 2016 (UTC)

External links modified
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 * Added archive https://web.archive.org/web/20101225182027/http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=888 to http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=888

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External links modified
Hello fellow Wikipedians,

I have just modified one external link on LR91. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
 * Added archive https://web.archive.org/web/20110604072940/http://www.astronautix.com/engines/lr87.htm to http://www.astronautix.com/engines/lr87.htm

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

Cheers.— InternetArchiveBot  (Report bug) 06:09, 11 November 2017 (UTC)