Japanese H-IIA Rocket successfully launches IGS Reconnaissance Satellite
A Japanese H-IIA launch vehicle lifted off from the country's picturesque launch site on Tanegashima Island at 1:21 UTC on Thursday, embarking on a mission to deliver the classified IGS Optical-5 satellite to a Low Earth Orbit to join Japan's fleet of Information Gathering Satellites.
The Information Gathering Satellites were approved for development in 1998 in response to a North Korean missile test that overflew the Japanese territory. At the time, Japan was relying on foreign satellite imagery that were only available after a certain delay and at significant cost.
The need of an independent capability to monitor activity on foreign territories to identify potential military threats was identified by the Japanese government that decided to press forward with the development of optical and radar reconnaissance satellites. The first launch of a pair of IGS satellites occurred in 2003 and over the years, over a dozen satellites were launched, going through constant improvements in capabilities and imagery resolution.
The IGS program is semi-secret up to a point where the Japanese government acknowledges its existence, however, details on the satellites are only available via secondary sources.
The IGS Optical-5 satellite is an operational fifth generation optical satellite that can achieve a ground resolution of better than 0.5 meters, joining an experimental 5th generation satellite that was launched in early 2013.
Launch Operations at the Tanegashima Space Center picked up around 11:30 UTC on Wednesday when the H-IIA rocket emerged from the Vehicle Assembly Building to make the 500-meter trip to the second launch pad at the Tanegashima Space Center.
Kicking off an overnight countdown, H-IIA - sitting atop the Mobile Launch Platform - was carefully centered on the pad and teams started the process of connecting the various propellant, pressurant, purge, power and data umbilicals. Next, a series of close out operations were completed at the launch pad before engineers departed the area to comply with the 400-meter safety zone for launch vehicle activation and testing.
With H-IIA on external power, the Launch Team started a series of testing operations looking at the electronics, Flight Control System, propulsion systems, Communication System and Flight Termination System. Engine slews on the first and second stage engines were performed and teams completed the final steps to start propellant loading.
Ahead of the initiation of fueling, the safety zone was widened to 3,000 meters and the Vehicle Assembly Building was cleared for launch. Illuminated on its launch pad, H-IIA headed into propellant loading operations around seven hours and 45 minutes prior to launch, picking up with the pressurization and chilldown of the Liquid Hydrogen and Liquid Oxygen Systems on the ground before transfer lines to the launcher were conditioned and the four propellant tanks on the two stages of the vehicle could enter chilldown.
Over the course of a three-hour sequence, the tanks of the H-IIA first stage were filled with about 100 metric tons of -183°C LOX and -253°C LH2 while the second stage received about 16,600kg of cryogenics. Entering topping, the tanks were kept at flight level as the supercold propellants naturally boiled off.
The fully-fueled launcher was put through another round of tests including a repetition of C- and S-Band comm checks, testing of the Flight Control system and verifications of various ground systems. The countdown entered a quiet period after testing was complete and teams and visitors were treated to a beautiful sunrise that could be seen from the sea-side launch complex.
The Terminal Countdown started at X-60 minutes marking the start of final reconfigurations of the H-IIA rocket for the Automated Countdown Sequence. A refined version of the flight parameters were loaded into the Flight Computers based on the latest measurements of conditions in the upper atmosphere. Weather was favorable for launch with clear skies, calm winds and warm temperatures.
The IGS Optical 5 satellite was switched to internal power as clocks ticked down, also being placed in flight mode to be ready for its trip into orbit. Teams made the final status check of all stations including the range and spacecraft team reported a GO to head into the Automated Countdown Sequence.
The precise launch time was programmed into all sequencers and the Automated Countdown commenced at X-4 minutes and 30 seconds to begin the highly choreographed process of transitioning H-IIA to its launch configuration. All launch vehicle parameters were continuously monitored by computers that were ready to trigger an abort in the event of any off-nominal indications.
The first step was the pressurization of the first stage tanks after the ground propellant feed was terminated at X-4:20. Pressurization took two minutes to complete. At X-3 minutes, the two-stage rocket was transferred from ground facility power to battery power - the Flight Termination System was switched to a fully independent power source to ensure the system could end the flight of H-IIA in the event of an in-flight failure.
With one minute on the countdown clock, the sound suppression system started pouring thousands of liters of water onto the launch pad to suppress the acoustic loads at booster ignition.
Launch vehicle ordnances were armed at X-30 seconds followed 12 seconds later by the Guidance System switching to flight mode. At X-11.5 seconds, the sparklers underneath the LE-7A Main Engine of the Core Stage ignited to burn off any residual Hydrogen that may be released during the Ignition Sequence.
Ignition sequence start was commanded at X-5.2 Seconds and the fuel and oxidizer valves of the main engine were opened and its turbopumps started spinning to flight speed. Engine ignition was carefully monitored by computers to ensure LE-7A reached its full liftoff thrust of 109,300 Kilograms.
When clocks hit zero, and LE-7A was up and running, the two Solid Rocket Boosters ignited and H-IIA blasted off under loud thunder with a total thrust of 575 metric tons. The rocket climbed vertically for a handful of seconds before beginning its pitch and roll maneuver to depart Tanegashima Island. No official broadcast by either JAXA of Mitsubishi Heavy was provided but amateur groups gathered at the launch site to cover the launch, providing live video and photos.
Although no information on the flight profile of H-IIA nor the target orbit of this mission were released, the mission design can very well be deduced from previous H-IIA mission to a polar orbit where IGS Optical 5, like all of its predecessors, is headed.
The satellites operate from orbits inclined 98°, an orbital inclination that can not directly be reached from Tanegashima, requiring H-IIA to use additional performance for a Dogleg maneuver - a powered turn during the ascent inserted into the trajectory to avoid any fragments of the rocket coming down over inhabited land masses.
Heading out to the south-east, H-IIA was to continue on that path throughout the booster-phase of the flight and into the late stages of first stage flight, reaching a downrange distance of over 100 Kilometers.
At that point, the vehicle was to gimbal its engine to turn westward to align itself with a south-westerly path towards a 98° orbit, avoiding the Philippines and frequented fishing areas.
Heading uphill, H-IIA passed Mach 1 about 75 seconds after liftoff followed by Maximum Dynamic Pressure as the launcher flew under the power of its cryogenic main engine and the twin boosters that did most of the work at that point in the flight.
Burning over 65 metric tons of solid propellant, each SRB delivered more than 230 metric ton-force of thrust to deliver the extra kick during the initial flight phase needed to get IGS into its planned orbit.
Thrust on the boosters tailed off after passing the T+100-second mark with computers detecting the pressure drop inside the boosters through onboard instrumentation, triggering the separation of the boosters that employed pyrotechnics and thrust struts that ensure a clean separation of both boosters.
With the boosters gone, only the LE-7A engine was powering the launch vehicle consuming 260 Kilograms of cryogenics per second to deliver 109,000 Kilogram-force of thrust.
Reaching an altitude of around 130 Kilometers, H-IIA separated its protective payload fairing to shed no-longer-needed weight since aerodynamic forces can no longer harm the satellite at this altitude.
Sticking to a standard mission profile, the first stage burned until six and a half minutes into the flight. Shutting down the LE-7A engine, the first stage was to initiate the staging process eight seconds after MECO, firing pyrotechnics that allow the 37-meter long stage to be pushed away from the second stage, clearing the engine.
After another six seconds, the LE-5B engine of the upper stage was to ignite on its only burn in this mission, heading directly for the target orbit which required the stage to fire for up to eight and a half minutes. LE-5B delivers 14,000 Kilogram-force of thrust and was planned to finish the dogleg maneuver.
Main Engine Cutoff was expected around 15 minutes after liftoff in an insertion orbit at an altitude of approximately 500 Kilometers. Spacecraft separation was to occur under 20 minutes into the mission to set the IGS satellite free for its mission dedicated to keeping a close eye on developments on the ground. Confirmation of a successful launch was provided by the Launch Team through nominal call-outs during the flight all the way to separation.
This was the second Japanese launch of the year and the second dedicated to the IGS program. The next IGS satellites will be launched in 2016. Still planned this year is the next flight of Japan's
H-II Transfer Vehicle on a resupply mission to the International Space Station expected to launch atop an H-IIB in mid-August while H-IIA is set for its first commercial launch late in the year, carrying the TelStar 12V satellite into orbit and also debuting an upgraded second stage. Towards the end of the year, H-IIA is also planned to launch the New X-ray Telescope (NeXT).
Information Gathering Satellites
Information Gathering Satellites are Japan's primary intelligence satellites operated to deliver reconnaissance for the military and intelligence services in the form of optical imagery and high-resolution radar data. IGS satellites carry an optical reconnaissance payload or a Synthetic Aperture Radar for remote sensing. The main purpose of the satellite program is to provide an early warning capability of missile launches. IGS was initiated in 1998 in response to a North Korean missile test that flew over Japan.
re-entry that occurred on July 26, 2012. IGS 1A has been in a stable orbit until early 2012 when it started dropping, indicating that the spacecraft had depleted its fuel tanks or stopped functioning. It decayed in July 2014.
The second IGS launch in November 2003 ended in failure and never arrived in orbit when a Solid Rocket Booster failed to separate from the H-IIA rocket.
The IGS 1 and IGS 2 satellites were first generation spacecraft achieving a ground resolution for optical images of 5 meters (color) and about 1 meter (panchromatic). Synthetic Aperture Radar resolution is believed to be better than 3 meters.
IGS 3A was launched by H-IIA in September 2006 and represented the second generation of optical satellites that achieve a resolution of one meter. The satellite operated from an orbit of 480 Kilometers.
The IGS 4 satellite pair launched in February 2007 and included an experimental third generation optical satellite with a ground resolution of better than one meter, and a second generation SAR spacecraft also achieving a resolution of one meter. The satellites were found in an orbit of 481 to 494 Kilometers that they maintained until 2010. In the summer months of 2010, IGS 4B became non-operational for reasons that were not disclosed - it re-entered in November 2013. When satellite 4A stopped functioning is unclear, but orbital data suggests a loss of orbit control between mid-2010 to mid-2011 leading up to re-entry in April 2014.
IGS 5A is another optical satellite of the third generation launched in late 2009 and found in an orbit of about 585 Kilometers. In September 2011, the first fourth generation optical satellite was launched that is believed to achieve image resolutions of about 60 centimeters, operating in an orbit similar to that of IGS 5A. The first satellite in the third generation of SAR spacecraft was launched in December 2011 and operates from a 510-Kilometer orbit.
Another dual-IGS launch occurred in January 2013 when an H-IIA202 rocket delivered IGS 8A and 8B into an orbit of 513 Kilometers. The 8A satellite is a 3rd generation SAR spacecraft and 8B a 5th generation optical satellite that returns imagery at resolutions of under 50 centimeters The. 8A satellite remains in its 513-Kilometer orbit while 8B has entered a lower orbit at an altitude of 427 Kilometers.
In January 2015, a satellite known as IGS Radar Spare (IGS 9A) entered orbit after a successful H-IIA launch, likely representing a 3rd generation satellite ordered as reserve for an earlier SAR satellite and being launched to be ready for the end of service of a SAR satellite, likely IGS 7.
Because the IGS Satellites are military intelligence spacecraft, details on their design and operation are not provided. IGS spacecraft are built by Mitsubishi Electric, likely based on a commercial satellite bus.
It is known that the spacecraft have a mass of about 1,000 to 1,400 Kilograms when launched in pairs and that power generation is accomplished by solar arrays. Satellites launched without a companion could be much heavier based on the payload capability of the H-IIA which can deliver up to four metric tons into an IGS-type orbit. Orbital data of IGS spacecraft is not provided regularly, but satellite trackers around the world have been keeping tabs on the constellation.
The IGS Optical 5 Satellite is an operational fifth generation optical satellite that follows in the footsteps of IGS IGS 8B satellite that serves an experimental role to confirm the functionality of the optical payload, clearing the instruments for operational deployment. Resolution of the 5th generation of optical satellites is believed to be better than 50 centimeters possibly as high as 40 centimeters.