top of page

Japan's H3 rocket fails on test flight

Second stage was destroyed after misfire

H3 Takeoff from Tanegashima

The second attempt to launch Japan's H3 rocket failed minutes after takeoff on Tuesday, March 7, 2023 – – as its second-stage engine failed to fire. and the country's space agency ordered the vehicle to self-destruct. Engineers at the Japan Aerospace Exploration Agency (JAXA), the rocket's developer, said they were unsure of the cause of the failure but were looking into the possibility that an electronic problem was involved, either in the control system or the second-stage engine itself. . The launch was carried out at 10:37, Tokyo time (JST) (20:37 EST on the 6th), from the Tanegashima space center, in Kagoshima prefecture, in the southwest of the country. The 574-tonne rocket was supposed to launch the ALOS-3 satellite, weighing about 3 tons, into orbit.

The launch on Tuesday's clear morning from Tanegashima, about 1,000 kilometers southwest of Tokyo, looked like a success during its early stages. The engineers were overjoyed with what they considered "perfect performance" from the rocket's main engine, which they had spent the last eight years developing. When the main engine was finally switched off after five minutes, they cheered, “Great job!” in the control center. But excitement gave way to disappointment when telemetry signals indicated that the second-stage engine failed to fire after first-stage separation. “My mind went blank,” said Masashi Okada, project manager at JAXA.

The two solid propellant thrusters leave the characteristic smoke trail

The failure marks a serious setback for Japan's space ambitions. Despite being much smaller than the US, Japan's space industry is a major global player, and Prime Minister Fumio Kishida's government sees it as crucial to the country's business and national security ambitions. On board the rocket was the Advanced Land Observating Satellite-3, an observation satellite that carried a missile early warning system for the Ministry of Defence. A launch attempt on February 17 was aborted at the last minute. JAXA said on March 3 that the failure was caused by electrical interference during the switch from the external power supply to the rocket's internal batteries at liftoff. Last year,

The H3 was developed at a cost of over 200 billion yen (US$1.5 billion). The launch was originally slated for fiscal 2020, but engineering issues caused delays. At 57.3 meters tall and 5.2 meters in diameter, the H3 is Japan's first upgrade in over 20 years and has been heralded as a more powerful, cheaper and safer successor to the H2A rocket, which is due to be retired. in fiscal year 2024. It is built by Mitsubishi Heavy Industries and was created to showcase Japan's manufacturing capabilities. It is the world's first rocket to use an expander cycle system in its main engine, instead of the gas generator that most rockets use. The new system was considered less prone to problems, but also less powerful. The H3 should have overcome this challenge.

The H3 also cut its launch costs in half to just $50 million – which JAXA estimates is less than the cost of SpaceX's Falcon 9 – by reducing the number of components and using automotive parts for 90% of the electronics. , as as sensors. At a press conference, JAXA President Hiroshi Yamakawa acknowledged that there is a link between cost and reliability, but denied that budgetary or time pressures played a role in the breakdown. “We only launch when we are confident” about the rocket's performance capabilities, he said. “Haste creates waste… I believe we never compromise on reliability.”

JAXA and Mitsubishi Heavy wanted to run the test by the end of the fiscal year in March to meet growing demand for launches after Russia's Soyuz rocket withdrawal from the international market following the war in Ukraine.

The failure is expected to further delay some of Japan's major space initiatives. The H3 would play a key role in the country's effort to double the number of its intelligence-gathering satellites to ten and place surveillance satellites in geostationary orbit. In the fiscal year starting in April, the country also plans to launch a navigation spacecraft carrying a US Space Force optical sensor. The H3 was expected to be handed over to Mitsubishi Heavy as a private deal, with the Japanese conglomerate having agreed to launch satellites for British telecommunications operator Inmarsat. Mitsubishi Heavy shares closed down 0.37% in Tokyo trade after the failed launch.

The rocket's first launch attempt was canceled because the SRB-3 auxiliary 'booster' activation signal was not issued. Development manager and project leader Masafumi Okada said that although the main engine had started to run normally, the first stage system had detected an anomaly. Takeoff was aborted because no signal was sent to ignite the booster. He added that the exact cause was yet to be determined. The statement was that they intend to keep the launch within the Japanese fiscal year, which ends March 31, pending detection and resolution of the outage. The first stage LE-9 engines apparently worked according to plan. The rocket will be airlifted with its ML-5 firing table tonight Japanese time, so the vehicle will be checked out.

The mission

The rocket will carry the remote sensing satellite ALOS-3 (“Daichi-3”) into a 669 km high sun-synchronous orbit inclined at 98.1 degrees. The ALOS developed by Mitsubishi Electric and should continue the series, whose first example was launched in 2006 and deactivated in 2011. The ALOS-3 is equipped with a camera with a higher resolution (0.8 m) with the same width of range (70 km) of predecessors to create high-quality color images. The second satellite in the series, ALOS-2, launched in 2014, continues to operate in orbit.

The satellite is planned to be used for continuous observation of the Earth's surface and its shooting, as well as for the prevention and prevention of natural disasters, monitoring the environment and coastal areas by sending high-precision geospatial data to Earth and will be able to transmit them to other optical repeater satellites.

Initially, the debut of the H3 was scheduled to take place in 2020, but it had to be postponed due to the detection of vibrations in the main engines. Last month, JAXA and Mitsubishi Heavy Industries Corporation, which developed the rocket, conducted a series of engine tests on the launch pad. Its results were considered successful, no problems were identified.

The primary purpose of the previous rockets, the H-IIA and H-IIB, was primarily government-led space development. This included launching national satellites and the Kounotori transfer vehicle, which transports supplies to the International Space Station (ISS). However, the H3 is aimed at private companies: the developer prioritized commercialization by creating a rocket that would provide “high satisfaction for the diverse needs of customers”. The H-IIA costs around ¥10 billion yen ($76 million) for a launch — more expensive than European and American rockets, making it less competitive. To mitigate this, the H3 was designed from the ground up to reduce costs. JAXA has emphasized the use of off-the-shelf material rather than specially developed parts. In fact, around 90% of the electronic components were replaced with readily available ones, such as car parts. As a result, the launch cost was halved to around ¥5 billion (US$38 million). By keeping the cost of launching each rocket at half the conventional price, the developers aim to appeal to a wide range of commercial demand, including launching satellites for overseas organizations.


ALOS-3 Daichi 3 will make observations of the ground and atmosphere

The ALOS 3 (Advanced Land Observation Satellite 3) is an optical Earth observation satellite to be used for cartography, regional observation, disaster monitoring and resource surveying. It is the continuation of the ALOS series optical component. Although high resolution and broadband are generally incompatible functions, ALOS-3 improves ground resolution by about three times that of the previous satellite (2.5 to 0.8 meters at nadir) while remaining in broadband (70 km at nadir). The satellite measures 5 m × 16.5 m × 3.6 m in orbit and weighs about 3 tons. The satellite will observe any point in Japan within 24 hours of receiving the request using the pointing function up to 60 degrees in all directions against the satellite's nadir. It will cover a wide area of ​​more than 200 km x 100 km by multiple scan observations during an orbital path.

Rocket, satellite and orbit depicted in the image

The main characteristics of the DAICHI-3 are: higher resolution of captured images; Increased observation wavelength range; Adoption of satellite optical communication. It was equipped with a sensor that acquires black and white images with a terrain resolution of 2.5m and a sensor that acquires color images with a terrain resolution of 10 meters. Equipped with 24 CCD (Charge Coupled Device) sensors, developed internally by Mitsubishi Electric, a total of twelve for black and white and twelve for color.

A new Japanese default launcher

The H3 ("H-3 rocket ") is Japan's largest liquid-fueled launch vehicle. Its length is 63 meters with a main diameter of 5.2 m and a payload capacity of 4 to 6.5 tons in geostationary orbit. It is intended to replace the H2A, which has been in operation since the early 2000s and which is one of the most reliable rockets in the world with 45 launches – of which 44 have been successful.

The H3 is Japan's largest liquid-fuel rocket. Its length is 63 meters (with the long fairing, unlike the model that will launch the ALOS-3, which is short) with a diameter of 5.2 meters and with a load capacity of 4 to 6.5 tons in transfer geostationary.

The H3 has two stages. The first stage uses liquid oxygen and liquid hydrogen as propellants and carries two or four solid propellant boosters (SRBs, derived from Model H-IIB SRB-A) using polybutadiene HTPB fuel. The first stage can be equipped with two or three LE-9 engines that use an expander bleed cycle design similar to the LE-5B engine. The mass of fuel and oxidizer of the first stage is 225 tons. The second stage is equipped with an improved LE-5B engine, and the propellant mass of the stage is 23 tons. JAXA expects the H3 to cut launch costs by nearly half, making Tokyo more competitive in the international commercial satellite launch market. Currently, an H2A launch costs Japan 10 billion yen ($75 million at current exchange rates).


bottom of page