 tons and the launcher can lift up to 4,100 Kilograms into a Geostationary Transfer Orbit.
H-IIA was moved to its launch pad at 9:30 UTC on Wednesday, marking the start of the lengthy launch countdown with final hands-on work at the launch pad to connect the launcher to ground systems ahead of detailed systems testing before propellant loading started at 16:31 UTC. Over the course of a three-hour sequence, H-IIA received 120 metric tons of -183°C Liquid Oxygen oxidizer and -253°C Liquid Hydrogen fuel for consumption by the rocket’s LE-7A and LE-5B engines.
Testing continued throughout the countdown and H-IIA was prepared for its automatic countdown sequence heading into the last hour of the day’s count. As the countdown switched to auto-mode at X-4.5 minutes, H-IIA pressurized its propellant tanks, transferred to internal power and switched to onboard control before activating thermal batteries and completing a final thrust vector control check on the boosters to clear the way for ignition.
H-IIA came to life at X-5.2 seconds when the LE-7A engine began its carefully controlled ignition sequence to roar to a thrust of 86 metric-ton-force before the twin boosters were fired up when clocks hit zero – catapulting the rocket off the ground with a thrust of 596 metric-ton-force. Climbing away from its sea-side launch pad, H-IIA maintained a vertical orientation for only a few seconds before its engine and boosters gimbaled to enter the pitch and roll program designed to align the vehicle with its south-easterly flight path across the Pacific Ocean.
The familiar scream unique to the H-II rocket series was heard across the Tanegashima Space Center as the vehicle accelerated downrange, passing Mach 1 and encountering Maximum Dynamic Pressure one minute into the flight, burning 1,600 Kilograms of propellant every second of powered flight.
The twin boosters, doing most of the work during the initial flight phase, helped accelerate the vehicle to a speed of 1.5 Kilometers per second as each delivered a thrust of 255 metric ton-force for a 98-second burn prior to thrust tailoff. Burnout of the 15-meter long boosters was sensed by their declining chamber pressure, triggering the Flight Control System to initiate the separation 108 seconds into the flight at an altitude of 54 Kilometers.
With the two boosters cleanly separating, H-IIA headed on toward orbit powered by the LE-7A engine alone, guzzling down 260 Kilograms of cryogenics per second to output a thrust of 109 metric ton force when flying through the thin upper atmosphere.
By X+4 minutes and 10 seconds, H-IIA had escaped the dense atmosphere and reached 150 Kilometers in altitude, allowing the fairing halves to be split open and separated to shed no-longer-needed weight and reveal the QZS-2 satellite for the rest of its ride into orbit. The first stage was to shut down its LE-7A engine six minutes and 38 seconds into the flight, having reached a speed of 5.2 Kilometers per second.
Six seconds after MECO, the 37-meter first stage dropped away from upper stage to hand powered flight off to the LE-5B engine set for a pair of burns during Thursday’s primary mission.
Firing up its 14,000 Kilogram-force LE-5B engine, the second stage was to continue on a south-easterly trek for a burn of five minutes and 48 seconds to push the stack into a Low Earth Parking orbit around 270 Kilometers in altitude. After shutdown on the second stage, H-IIA entered a coast phase of exactly 12 minutes to reach the proper position for the second burn that was designed to set the high point of the orbit.
Instead of a mission to Geostationary Transfer Orbit that aims to minimize inclination, H-IIA was actively working to increase orbital inclination on Thursday, targeting a highly elliptical orbit of 250 by 36,140 Kilometers, inclined 31.9 degrees.
— なりたまさひろ (@naritamasahiro) June 1, 2017
The second stage re-started its engine 24 and a half minutes into the flight on a planned burn of three minutes, expected to raise the vehicle’s speed by 2.5 Kilometers per second to accomplish the high-energy injection