Regarding the large “H3” rocket in development with the goal of its first launch next year, the Japan Aerospace Exploration Agency (JAXA) injects ultra-low temperature liquid fuel into the first aircraft and counts down to just before the launch “ultra-low temperature inspection”. It was held at the Tanegashima Space Center (Minamitane City, Kagoshima Prefecture). Although some work was stopped due to bad weather, the inspection data is said to have been obtained well.
Cryogenic inspection is a combination of the aircraft and equipment at the launch point to verify the content of the work until launch. It was a major milestone in the development and was held from the 17th to the 18th. The H3, which first appeared from the assembly building in the early morning hours of the 17th, was placed on the mobile launch pad and moved to the launch point. about 380 meters away. Connect pipes such as electrical cables and fuel. Starting in the afternoon of the same day, fuel was injected for approximately 4 hours, and at the same time the aircraft and equipment were inspected and functions confirmed. The countdown advanced to 6.9 seconds before the engine fired towards the estimated launch time of 1: 9 am on the 18th, and the procedure was verified. Subsequently, the fuel was unloaded and returned to the assembly building in the afternoon of the same day, and a number of works were completed.
In this inspection, the actual machine is used for the main body of the aircraft and the solid booster rocket attached to the side of the main body. No artificial satellites were mounted, and the fairing (satellite cover) on top was different from the white on the real machine, and black was used for testing. The “LE9” first stage engine was also being tested.
JAXA’s project manager Masashi Okada, who met on the morning of the 18th after completing the main work, explained that he had successfully acquired a series of data such as aircraft movement, work at the launch point, the countdown and reception of radio waves from the ground. monitoring station. “It is almost perfect in the school test. There were no major reworks in the final stage of combining the system, so I am not relieved, but I am relieved. Development has crossed one of the great mountains. I will continue to do my best to finish H3.
The work was suspended due to heavy rains. Also, it takes time to prepare for the fuel injection, the pipes for the air conditioning inside the aircraft, the adjustment of the gas system to pressurize the fuel tank, etc., and it will be approximately 5 and a half hours from the plan when the countdown starts 60 minutes before expected launch. Time has passed. We planned to count down twice, but due to increased fear of lightning, we decided we could get enough data once and canceled the second time. We focused on the high-priority items and proceeded with verification.
The current “H2A” is attractive to the commercial launch market as an “on-time launch” that will launch at the scheduled time with great precision, except in case of postponement due to bad weather. Regarding the fact that the H3 job took longer than planned, Mitsubishi Heavy Industries project manager Tokio Nara said: “It was a development test and it took time because we proceeded carefully and worked while correcting the problems. I would like to improve the training level by reflecting the above, and finish it so that it can be operated smoothly and established at launch. We are developing it as a rocket for launch on time.
The H3 was found to be damaged in the LE9 combustion test in May last year, with the first launch scheduled for this year postponed to next year. Regarding the current state of LE9, Project Manager Okada described it as “the final stage to solidify the design.
The H3 is the successor to the H2A and the improved “H2B” that was in operation until May last year. Development is underway to respond to the increase in the size of artificial satellites and the reduction of costs in the global market. Like the H2A, it is a two-stage type that uses liquid fuel, but the LE9 uses Japan’s unique combustion method that has been used in the second-stage engine. The number of parts has been significantly reduced compared to the conventional method, and the mechanism and control have been simplified. We will also promote the introduction of new technologies and consumer products such as automobiles, with the aim of halving the launch cost, which is estimated at about 10 billion yen for the entry-level H2A model. The maximum capacity (geostationary transfer orbit) is 6.5 tons or more, which exceeds 6 tons of H2B.