User:Andrewa/LR-87 versions

From Wikipedia, the free encyclopedia

This is a temporary repository for engine stats.

It's here to help with the program of reviewing all LR-87 articles to check that the stats quoted (such as weight and thrust) aren't low by a factor of two as a result of being quoted for only one combustion chamber and nozzle, see Talk:LR-87#Engine versions.

Feel free to update with additions and corrections.


I too have had a bit of trouble pinning down weight, dimensions, and performance numbers for the various LR87 versions.

I have some LR87 numbers for you from a reputable source.[1]

Sutton worked for Aerojet 3 years and Rocketdyne for over 25 years. His book "Rocket Propulsion Elements" has been in print since 1949


Titan I LR87-AJ-3

Thrust = 382,000 (lbs vacuum)

Thrust = 300.000 (lbs sea level

Specific Impulse = 258.8 (S sea level)

Specific Impulse = 315/329 (Is S vacuum)

Propellants = LOX/Kerosene (RP-1?)

Mixture Ratio = 202

Chamber Pressure = NA (psia)

Nozzle Area Ratio = 8


Titan II LR87-AJ-5

Thrust = 473,800 (lbs vacuum)

Thrust = 430.000 (lbs sea level

Specific Impulse = 278 (S sea level)

Specific Impulse = 285.2//309 (Is S vacuum)

Propellants = NTO/Aerozine 50

Mixture Ratio = 1.930

Chamber Pressure = 795 (psia)

Nozzle Area Ratio = 8


Titan II LR87-AJ-5

Thrust = 473,800 (lbs vacuum)

Thrust = 460.000 (lbs sea level

Specific Impulse = 258.8 (S sea level)

Specific Impulse = 285.2/309 (Is S vacuum)

Propellants = NTO/Aerozine 50

Mixture Ratio = 1.930

Chamber Pressure = 795 (psia)

Nozzle Area Ratio = 8


Titan III LR87-AJ-11

Thrust = 527,800 (lbs vacuum)

Thrust = 430.000 (lbs sea level

Specific Impulse = 258 (S sea level)

Specific Impulse = 296/318 (Is S vacuum)

Propellants = NTO/Aerozine 50

Mixture Ratio = 1.75

Chamber Pressure = 823 (psia)

Nozzle Area Ratio = 12


Titan IV LR87-AJ-11A

Thrust = 550,900 (lbs vacuum)

Thrust = 489.000 (lbs sea level

Specific Impulse = NA (S sea level)

Specific Impulse = 303.5/316.2 (Is S vacuum)

Propellants = NTO/Aerozine 50

Mixture Ratio = 1.91

Chamber Pressure = 854 (psia)

Nozzle Area Ratio = 16

Mark Lincoln (talk) 19:19, 16 February 2016 (UTC)


You Have the Nomenclature Wrong

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 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)"[2]


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."[3]

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.

Mark Lincoln (talk) 18:12, 16 February 2016 (UTC)

  1. ^ Sutton, George P, History of Liquid Propellent Rocket Engines, Reston Virginia: American Institute of Aeronautics and Astronautics, 2006, ISBN 1-56347-649-5, p. 382
  2. ^ "Correct Designations for Jet, Turboprop, Pulse Jet,Ram Jet and Rocket Engines" (PDF). Aircraft Engine Historical Society. Retrieved 2015-08-12.
  3. ^ United States Air Force, The T.O. 21M-HGM25A-1-1 Technical Manual Operation and Organizational Maintenance HGM-25A Missile Weapon System, United States Air Force, 1964, paragraph 1-243