Test Firings Begin on Japanese LE-5B-3 Engine

Test firing of LE-5B-3 engine. (Credit: JAXA)

TOKYO (JAXA PR) — JAXA tested LE-5B-3, the liquid rocket engine designed to propel the second stage of H3 Launch Vehicle now under development. LE-5B-3 enhances the LE-5B-2 engine that likewise boosts the second stage of H-IIA and H-IIB. LE-5B-2 has earned the time-tested record of reliability after scores of successful H-II launches. Improvements are being made to lower the cost of LE-5B-3, without compensating the dynamics to blast off H3, a larger rocket and to sustain its flight.

Following the design improvements for affordability and performance which reached the desired level in August 2016, JAXA successfully conducted the test of the liquid hydrogen turbopump in December 2016 through January 2017. The liquid hydrogen turbopump — equivalent of the heart of a human body — draws in the propellants into the engine thrust chamber.

Since March 2017, the first engine with the hydrogen turbopump, assembled for certification was completed, kicking off its preliminary firing testing. The test is proceeding on schedule. By September 2017, test results will expectedly prove the soundness of the basic design improvements.


JAXA Begins Tests of H-III Engines

H-III launch vehicle variants (Credit: JAXA)

The Nikkei Asian Review reports JAXA began test firings of the LE-9 rocket engine, which will power its new H-III launch vehicle. The first round of testing will include 11 firings through June.

The new booster is set to replace the H-IIA and H-IIB launchers, which are the mainstay of Japan’s orbital rocket fleet. Mitsubishi Heavy Industries and IHI are leading the development of the new two-stage launch vehicle.

H-III is designed to launch payloads at lower costs. The basic configuration can carry 4 metric tons into sun synchronous orbit.  By adding two to four strap-on boosters to the first stage, H-III will be able to lift up to 6.5 metric tons into geostationary transfer orbit.

The new booster will have a base cost of about 5 billion yen ($43.9 million). The H-IIA costs an estimated 10 billion yen ($87.8), with the more powerful H-IIB costing 10 billion yen ($131.5 million).

JAXA’s goal is for the H-III to complete flight tests and enter service in March 2021.