Talk:Titan II GLV

How many engines

The first stage has only one engine, but with two nozzles, see LR-87. Andrewa (talk) 16:53, 24 November 2012 (UTC)

Number of first stage engines

There is a discussion at Talk:LR-87#Number of nozzles and Talk:LR-87#Affected articles that affects this article. Please discuss it there. Andrewa (talk) 23:42, 17 March 2014 (UTC)

This article is listed at [[Talk:LR-87#Affected articles as one of those affected by the proposal at Talk:LR-87#Consensus? to treat all variants of the LR-87 as a single engine with two nozzles. Please raise any objections to this there.

If no objections are received, the proposal will in due course take effect in this article. Andrewa (talk) 08:23, 26 March 2014 (UTC)

The USAF considered the LR87 as 1 engine with 2 thrust chambers. "T.O. 21M-HGM25A-1-1 Technical Manual Operation and Organizational Maintenance HGM-25A Missile Weapon System" makes that very clear. Figure 1-60 "Stage I Rocket Engine Subassembly", on page 1-102, lists item 15 as Thrust Chamber 1, and item 17 as Thrust Chamber 2. Paragraph 1-243 (page 1-101) states "STAGE I ROCKET ENGINE. The Stage I rocket engine, designated LR87-AJ-3, consists of two engine subassemblies. (See figure 1-60.) The two subassemblies develop a total of 300,000 pounds of thrust and are mounted on a common engine frame . . . The subassemblies are similar and are interconnected by instrumentation and electrical components."

Sutton in "History of Liquid Propellent Rocket Engines" states "The booster engine has twin LPREs with regeneratively cooled gimbal-mounted thrust each with it's own turbopump."

Mark Lincoln (talk) 21:49, 17 February 2016 (UTC)

References

Engine name change

For reasons unknown it has become common to insert a hyphen in the names of military jet and rocket engines. The reason I changed the designations was simple and well documented.

There is no LR-87 and never was. The proper nomenclature is LR87. 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 from a 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)"

What did the United States call the Titan I engines?

The USAF "T.O. 21M-HGM25A-1-1 Technical Manual Operation and Organizational Maintenance HGM-25A Missile Weapon System" defines the first stage engine in paragraph 1-243 (page 1-101) as: "STAGE I ROCKET ENGINE. The Stage I rocket engine, designated LR87-AJ-3, consists of two engine subassemblies."

The designation means Liquid Rocket #87 AeroJet second USAF version. The first USAF version was the LR87-AJ-1, the third USAF version LR87-AJ-5 was used in the Titan II.

There is no LR-91 and never was. The proper nomenclature is LR91.

The United States Air Force call the Titan I engines?

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.

Certainly the USAF knew what the names of the Titan I engines were.

Consider the description on Don Boelling's Titan II site http://www.titan2icbm.org/titanD.html

The LR87-1-AD-3 was an amazing engine. It is one of the very few large liquid propellant engines to run on three different propellant combinations. Liquid Oxygen/RP-1 as in Titan I, Nitrogen Tetroxide/Arozine 50 in an experiment in development of the RL87-AJ-5 for the Titan II, and Liquid Oxygen/Liquid Hydrogen as an experiment.

Over 1500 LR87s were built in over 47 years.

Mark Lincoln (talk) 21:49, 17 February 2016 (UTC)

References