Japan Conducts Tests on H3 Rocket’s LE-9 Engine to Address Instability Issues

LE-9 engine (Credit: JAXA)

TOKYO (JAXA PR) — We are pleased to inform you that the combustion test (blade vibration measurement test) of the LE-9 engine currently under development by JAXA as the first stage liquid fuel engine of the H3 rocket will be conducted as follows.

The LE-9 engine is considering multiple proposals in parallel as countermeasures to the problems that occurred in the past tests, and this test is to verify to narrow down the countermeasure proposals.

Test nameLE-9 engine wing vibration measurement test
Test purposeCheck the vibration response of the turbopump blades to verify one of the countermeasures for the LE-9 engine problem.
PeriodMarch 23, 2022 (Wednesday) -April 2022 (planned)
PlaceJapan Aerospace Exploration Agency Tanegashima Space Center (Kagoshima Prefecture)
Number of tests4 times (planned)

* The period and number of tests may change depending on the weather and work progress.

Test No. 1

We are pleased to inform you of the results of the first LE-9 engine combustion test announced on March 22, 2022.

Test dateMarch 23, 2022
Testing locationJapan Aerospace Exploration Agency Tanegashima Space Center (Kagoshima Prefecture)
Test purposeCheck the vibration response of the turbopump blades to verify one of the countermeasures for the LE-9 engine problem.
Ignition time16:07
Test time36.3 seconds (72.2)
Main combustion pressure8.672MPa (9.36)
Liquid hydrogen turbopump rotation speed39,866 rpm (40,900)
Liquid oxygen turbopump rotation speed16,248 rpm (17,104)
RemarksThe vibration response of the blades of the liquid hydrogen turbopump reached a preset constraint, so it was manually stopped. In the future, we will proceed with detailed evaluation of the acquired data and preparations for the next test.

* The value in () is the planned value.

Test No. 2

We are pleased to inform you of the results of the second LE-9 engine combustion test announced on March 22, 2022.

Test dateMarch 30, 2022
Testing locationJapan Aerospace Exploration Agency Tanegashima Space Center (Kagoshima Prefecture)
Test purposeCheck the vibration response of the turbopump blades to verify one of the countermeasures for the LE-9 engine problem.
Ignition time15:53
Test time245.7 seconds (247.0)
Main combustion pressure9.06MPa (9.07)
Liquid hydrogen turbopump rotation speed39,844 rpm (39,938)
Liquid oxygen turbopump rotation speed16,446 rpm (16,445)
RemarksSince the rotation speed of the liquid oxygen turbopump reached the preset limit, it automatically stopped as planned. In the future, we will proceed with detailed evaluation of the acquired data and inspection of specimens.

* The value in () is the planned value.