Japanese H3 Rocket Triumphs in Successful Payload Deployment After Previous Setback

Space News ,Japan :- On the evening of February 16, the H3 rocket achieved a significant milestone by successfully deploying its payloads into orbit. This success marks a remarkable recovery from its debut flight failure last year, positioning the H3 as Japan's promising future workhorse rocket.

During a live webcast provided by the Japan Aerospace Exploration Agency (JAXA), a commentator expressed their excitement, stating, "I was so moved! The story of H3 will begin from today." JAXA offered real-time English translations for the original Japanese comments.

JAXA, in collaboration with Mitsubishi Heavy Industries, has dedicated a decade to the development of the H3 rocket. Designed as an expendable, medium-lift rocket, it is set to replace the venerable H-2A, which has been in operation since 2001 and is scheduled for retirement later this year.

Standing at either 187 feet or 207 feet (57 or 63 meters), depending on the choice of payload fairing, the two-stage H3 is equipped with newly developed liquid hydrogen-liquid oxygen LE-9 engines for the first stage. The upper stage features a single LE-5B-3, an advanced variant of the upper-stage engine on Japan's previous H-1 and H-2 vehicles.

Configurable with two or four solid rocket boosters, the H3 can haul over 7.2 tons (6.5 metric tons) of payload to geostationary transfer orbit (GTO) in its most robust configuration. This is a significant improvement over the H-2A, which can deliver about 4.4 tons (4 metric tons) to GTO. Furthermore, the H3 is expected to be more cost-effective to build and operate, according to JAXA officials.

Originally targeted for a 2020 debut, the H3 faced development delays, primarily due to challenges in developing the LE-9 engine. It eventually launched on March 6, 2023, carrying the Advanced Land Observing Satellite-3 (ALOS-3), also known as DAICHI-3, on its debut mission.

However, the debut mission encountered issues as the H3's second-stage engine failed to ignite due to an electrical problem, resulting in the loss of the satellite.

After almost a year, the H3 took off again from Japan's Tanegashima Space Center on February 16 at 7:22 p.m. EST (0022 GMT and 9:22 a.m. Japan Standard Time on Feb. 17). This time, it successfully carried two small Earth-observation satellites, CE-SAT-IE and TIRSAT, along with a 5,900-pound (2,600 kilograms) mass simulator called the Vehicle Evaluation Payload-4.

The mission's primary goal was to evaluate the H3 rocket's performance and its payload deployment mechanism. Impressively, the rocket achieved all required milestones on time, including the successful ignition of its upper-stage engine, which had encountered issues in the previous mission.

The upper stage reached orbit and deployed CE-SAT-IE, followed by the planned deployment of TIRSAT and the payload simulator. In a postflight update, JAXA confirmed the successful separation and controlled re-entry of the second stage, verifying the separation of the Vehicle Evaluation Payload-4 (VEP-4).

The triumphant success of the H3's recent mission marks a significant step forward, solidifying its position as a reliable and resilient rocket for Japan's future space endeavors.