Mitsubishi Heavy Industries Exhibits the QZS-3 Launch Vehicle
Mitsubishi Heavy Industries, Ltd. (MHI) exhibited to members of the press the H-IIA Launch Vehicle No. 35, which will be used to launch the third Quasi-Zenith Satellite (QZS-3), on June 27 at the Tobishima Plant in Tobishima Village, Ama District, Aichi Prefecture. The exhibition included the first- and second-stage frames (core frame), excluding the payload fairing (the nose cone that protects the satellite) and solid rocket boosters (SRB-As) installed on the outside of the first-stage frame.
Equipped with four SRB-As
Before the exhibition, Mr. Koki Nimura (fellow, senior chief engineer, Integrated Defense & Space Systems, MHI), who is in charge of the H-IIA and H-IIB launches, gave an overview of the launch plan.
The H-IIA Launch Vehicle No. 35 frame configuration is a H2A204 launch vehicle utilizing four SRB-As. The H-IIA Launch Vehicle No. 34 used in the QZS-2 launch on June 1 had two SRB-As, but this number has been increased to four for improved launch performance. This is because QZS-3 has a launch mass of 4,700 kilograms, around 700 kilograms more than QZS-2 at 4,000 kilograms.
The fairing, which contains the satellite, is a single-launch type for one satellite. QZS-2 had a 4S-model fairing with a diameter of four meters, while QZS-3 has a 5S-model fairing with a diameter of five meters. Unlike QZS-2 and QZS-4, QZS-3 is equipped with message communication antennas and has a depth exceeding four meters, which is why the larger 5S model was adopted. This is the first time a 5S-model fairing has been used in roughly 11 years, since the H-IIA Launch Vehicle No. 11 was launched in December 2006.
QZS-3 has a control unit (EAC2) to operate the electric actuator that pilots the second-stage engine. Its two control operation modules have been integrated into a single module to cut costs. At the time of the launch, the rocket will have a total length of 53 meters, 12 meters of which is the payload fairing and 15 meters of which is the SRB-As.
Launch planned for August 11
Functional tests have been completed for the core frame, which will be shipped via sea and land from the Tobishima Plant to the Japan Aerospace Exploration Agency’s (JAXA) Tanegashima Space Center, the launch site. Mr. Nimura described his enthusiasm about the launch, saying, “We cannot rest until the final confirmation is completed at the launch site. Right now, I want to fully and perfectly execute all of our tasks with precision.”
The SRB-As have already been fueled at the launch site and will be installed after the core frame is stood up in the Vehicle Assembly Building (VAB). The launch is scheduled for around 2:00 p.m. to 11:00 p.m. (Japan Standard Time) on August 11. According to the launch plan, the launch vehicle will fly over the Pacific Ocean and QZS-3 will be separated roughly 28 minutes and 40 seconds later on a geostationary transfer orbit with an altitude of perigee of 380 kilometers, altitude of apogee of 35,976 kilometers, and inclination of 20 degrees (after, the satellite’s internal small rocket engine will propel QZS-3 onto its prescribed geostationary orbit [GEO]).