LE-7

LE-7
LE-7, Nagoya City Science Museum, 2006
Country of originJapan
DesignerJAXA
ManufacturerMitsubishi Heavy Industries
ApplicationBooster
StatusSucceeded by LE-7A upgrade
Liquid-fuel engine
PropellantLOX / LH2
Mixture ratio5.9:1
CycleStaged combustion
Configuration
Chamber1
Nozzle ratio52:1
Performance
Thrust, vacuum1,078 kN (242,000 lbf)
Thrust, sea-level843.5 kN (189,600 lbf)
Thrust-to-weight ratio64.13
Chamber pressure12.7 MPa (1,840 psi)
Specific impulse, vacuum446 seconds (4.37 km/s)
Specific impulse, sea-level349 seconds (3.42 km/s)
Dimensions
Length3.4 m
Dry mass1,714 kg (3,779 lb)
Used in
H-II first stage
LE-7A, (Mitsubishi Heavy Industries show-room, Shinagawa, Japan)

The LE-7 and its succeeding upgrade model the LE-7A are staged combustion cycle LH2/LOX liquid rocket engines produced in Japan for the H-II series of launch vehicles. Design and production work was all done domestically in Japan, the first major (main/first-stage) liquid rocket engine with that claim, in a collaborative effort from the National Space Development Agency (NASDA), Aerospace Engineering Laboratory (NAL), Mitsubishi Heavy Industries, and Ishikawajima-Harima. NASDA and NAL have since been integrated into JAXA. However, a large part of the work was contracted to Mitsubishi, with Ishikawajima-Harima providing turbomachinery, and the engine is often referred to as the Mitsubishi LE-7(A).

The original LE-7 was an expendable, high efficiency, medium-sized motor with sufficient thrust for use on the H-II.