|
H-IIA Flight 24 Launch Updates
Ascent Data, ALOS-2 Overview, Secondary Payloads, Launch Vehicle Overview, Japanese Archive
After the rollout, H-IIA was ready for its overnight launch countdown that started with several hours of hands-on work by engineers at the launch pad. Teams at the launch pad connected the vehicle to ground data and power systems and also made umbilical connections for propellant loading. Later, the pad facilities and the launcher were closed out and teams departed the pad at 17:30 UTC as the 400-meter security zone came into effect. Teams also buttoned up the Vehicle Assembly Building for launch.
With the opening of the launch window programmed into all sequencers on the ground and the launch vehicle, clocks started ticking at X-4 minutes and 30 seconds marking the start of the Automated Countdown Sequence. Throughout those final countdown minutes, computers choreographed the events of the countdown and monitored all vehicle parameters ready to trigger an abort in case of problems during the countdown.
On its way uphill, H-IIA passed Mach 1 after about 75 seconds powered by its two Solid Rocket Boosters and liquid-fueled core stage. Maximum Dynamic Pressure was encountered a few seconds later as the launcher made its way through the dense atmosphere.
Each SRB-A3 – an improved version of the SRB-A – measures measures 15.2 meters in length and 2.5 meters in diameter, burning through 66,000 Kilograms of propellants to provide 235,000 Kilogram-force of thrust. The twin boosters burned out one minute and 50 seconds into the flight when the vehicle was 47 Kilometers in altitude traveling 1.6 Kilometers per second. After sensing the pressure drop in the boosters that had consumed all their fuel, the H-IIA triggered booster separation at T+2:05 by severing the thrust struts of the two boosters that also ensured a clean jettison. The two boosters were headed for a splashdown in the Pacific, downrange from the launch site. With the boosters gone, H-IIA was only powered by its LE-7A engine consuming 260 Kilograms of Liquid Oxygen and Liquid Hydrogen per second delivering 109 tons of thrust. Boosting the stack out of the atmosphere, the first stage continued to stick to the pre-planned trajectory and attitude profile.
Main Engine Cutoff occurred at T+14 minutes and 56 seconds when the stack had reached its orbital velocity of 7.5 Kilometers per second. Orbital insertion occurred at an altitude of 633 Kilometers, 2,400 Kilometers downrange from the launch site. Immediately after shutdown, the second stage re-oriented for the separation of the ALOS-2 spacecraft, also known as Daichi.
Following its initial flight phase, ALOS-2 enters commissioning – a process that takes several weeks to verify the performance of all systems and begins to operate the SAR payload to start instrument commissioning and data validation. After several weeks, ALOS-2 transitions to normal mission operations to deliver regular L-Band radar images.
After the release of ALOS-2, H-IIA continued its mission to release the four secondary payloads – Rising-2, UNIFORM-1, SOCRATES and SPROUT. The satellites were to be released as part of a sequential procedure starting at T+25 minutes and deploying one satellite every 4 minutes and 10 seconds. The four satellites are dedicated to scientific missions, technical demonstrations and outreach projects. SPROUT, SOCRATES, UNIFORM-1 & Rising-1 Microsatellites
|
|
ALOS-2 - the Advanced Land Observation Satellite 2 is a radar Earth Observation satellite operated by the Japanese Aerospace Exploration Agency to acquire high-resolution radar imagery of Earth for cartography, regional observation, resource management, disaster management and scientific purposes. The satellite is the follow-on project to ALOS-1 that was launched in January 2006 and operated for five years until experiencing a complete power loss in 2011.
ALOS-2 will enhance the capabilities of the previously flown SAR payload on ALOS and provide an increased resolution, faster revisit times, and observation at high incidence angles. ALOS-2 was manufactured by Mitsubishi Electric Corporation under contract by JAXA to facilitate two primary instruments - the PALSAR-2 Phased Array L-Band Synthetic Aperture Radar, a Compact Infrared Camera - and a small AIS (Automatic Identification System) terminal. The spacecraft weighs 2,120 Kilograms and is 9.9 by 16.5 by 3.7 meters in size when fully deployed on orbit. ALOS-2 uses a modular approach consisting of a bus module, the large L-Band SAR antenna, a payload electronics unit and two small payload modules for the Compact Infrared Camera and the Space Based Automatic Identification System Experiment 2. The main instrument of the ALOS-2 spacecraft is PALSAR-2 - the Phased Array L-Band Synthetic Aperture Radar-2 that uses Active Phased Array Antenna technology. Radar satellites bounce radar signals off the ground and record the weak echo signal to deduce radar reflectiveness of sites on the ground which differs between the various types of vegetation, water bodies and man-made structures. Overall, the system consists of two main components: the antenna subsystem and the electric unit. The antenna is 2.9 meters wide and 9.9 meters long weighing 548 Kilograms. The Compact Infrared Camera CIRC is a small payload developed by MELCO under contract from JAXA using COTS (Commercial off the Shelf) components to build a compact infrared imager for deployment on several spacecraft to create an operational wildfire detection capability. >>>Detailed ALOS-2 Spacecraft Overview |
Rising-2
Rising-2 is a microsatellite project of Tohoku University and Hokkaido University, Japan, to create an Earth observation satellite with a resolution of 5 meters for the study of cumulonimbus clouds and upper atmospheric lightning (Transient Luminous Events).
The primary instrument of Rising-2 is the High Precision Telescope featuring a Cassegrain Design to be used for Earth Observations and the observation of Transient Luminous Events. The telescope has a field of view of 0.27 by 0.2 degrees corresponding to 3.3 by 2.5 Kilometers on the ground. The Bolometer Array Instrument is an uncooled infrared imager covering a spectral range of 8 to 14 micrometers (thermal infrared). It is used to acquire images of cumulonimbus cloud regions, ground surfaces and maritime areas for a variety of purposes. Imagery provided by the instrument can be used to determine the temperature of the top region of cumulonimbus from which the altitude of the clouds can be deduced. Rising-2 is equipped with two Lightning and Sprite Imagers that feature identical detectors but are equipped with different passband filters. The two cameras will be used to detect Transient Luminous Events such as sprites and elves above thunderstorm clouds as well as lightning emissions at lower altitudes. The Rising-2 Wide Field Camera will be used to detect the location of lightning flashes and Terrestrial Gamma-ray flash events. A Very Low Frequency Receiver VLFR is installed on the satellite to record the low-frequency signatures of lightning events. >>>Detailed Secondary Payload Overview |
SOCRATES
SOCRATES - the Space Optical Communications Research Advanced Technology Satellite is a microsatellite project of the National Institute of Information and Communications Technology in Japan. The primary objective of the mission is the demonstration of a Small Optical TrAnsponder SOTA - a laser communications terminal for use in space flight applications.
The main payload of SOCRATES is SOTA - the Small Optical Transponder that will be used to demonstrate a compact laser communications terminal for use on satellites, microsatellites and nanosatellites. The objectives of the mission are the verification of on orbit acquisition, tracking and communication performance of the small optical terminal as well as the collection of data associated with propagation through the atmosphere at various wavelenghts. >>>Detailed Secondary Payload Overview |
UNIFORM-1
The overall goal of the Uniform program at Wakayama University is the development of a wildfire monitoring system using a constellation of microsatellites to achieve a high-time resolution at a comparable low cost.
The Uniform-1 satellite is based on a 50 by 50 by 50-centimeter satellite structure with a mass of under 50 Kilograms. The spacecraft carries two primary instruments - a microbolometer array for infrared imaging and a visible imaging payload. The main payload of the satellite consists of a Microbolometer Array that is used for imaging in the thermal infrared spectral band between 10 and 12 micrometers. The Microbolometer Array achieves a ground resolution of 100 meters over a swath width of 100 Kilometers. UNIFORM-1 will acquire high resolution optical images of targets to provide imagery to better locate and asses wildfires and help in response efforts. >>>Detailed Secondary Payload Overview |
SPROUT
SPROUT is a project of Nihon University and stands for Space Research On Unique Technology.
The main payload of the SPROUT spacecraft is an external membrane that is triangular in shape and measures 1.5 meters. The membrane is expanded by Nitrogen gas fed from a cartridge that deploys two tubes to which the membrane is attached. This membrane experiment serves as a pathfinder for future spacecraft utilizing solar sails for power generation. Additionally, the experiment will yield measurements of orbital drag by recording the orbital parameters of the spacecraft with its membrane deployed and experiment with the attitude of the satellite to provide data for orbital modeling for future missions. >>>Detailed Secondary Payload Overview |
One LE-5B engine powers the second stage providing a vacuum thrust of 137kN. The engine can make multiple ignitions to target a variety of orbits.
>>>H-IIA Launch Vehicle Overview >>>Live Launch Coverage >>>Countdown Timeline >>>F24 Ascent Data The Launch Countdown operation for H-IIA begins about 14 hours before launch with the rollout of the launcher from its final assembly building. The trip from its assembly building to the sea-side launch pad - located at the South-Eastern tip of Tanegashima Island - South of Kyushu, the southernmost of Japan's main islands takes about 30 minutes.
At X-3 minutes, the launch vehicle is switched to internal power while ALOS-2 will have been switched to battery power ahead of the final countdown sequence. One minute before liftoff, thousands of Kilograms of water are being poured over the launch platform to suppress the acoustic loads at ignition & liftoff. Launch Vehicle Ordnances will be armed at X-30 Seconds and the Guidance System of the Vehicle is being switched to Flight Mode 12 Seconds later before the sparklers underneath the LE-7A main engine ignite to burn off residual Hydrogen.
The first stage will continue to burn until T+6 minutes and 36 seconds, boosting the vehicle to a velocity of 3.2 Kilometers per second. Stage separation occurs eight seconds after MECO at an altitude of 311 Kilometers and the second stage will prepare for its ignition.
The single LE-5B engine will ignite six seconds after staging, at T+6:50, reaching its full thrust of 13,970 Kilograms for a burn of more than eight minutes. The mission is targeting an orbit of 628 Kilometers at an inclination of 97.4 degrees.
|
Afterwards, operations will transition to commissioning to test the radar instrument and prepare for normal mission operations that get underway several weeks after launch.
JAXA prepares to Launch large Radar Satellite aboard H-IIA
|
May 7, 2014
|
|
The Japanese Aerospace Exploration Agency and Mitsubishi Heavy Industries are gearing up for the launch of an H-IIA rocket carrying the Advanced Land Observation Satellite-2. Launch is currently planned for May 24 during a 15-minute window opening at 3:05 UTC. In addition to ALOS-2, H-IIA will deliver four secondary payloads to orbit – the scientific Rise-2 satellite that will observe lightning in the upper atmosphere, the SOCRATES satellite that will demonstrate a laser communications terminal for small satellites, UNIFORM-1 a prototype wildfire monitoring satellite and SPROUT – a small technical demonstrator and outreach satellite.
Preparations for the launch are underway at the Tanegashima Space Center where MHI is preparing the H-IIA launch vehicle that was delivered to the launch site in early April and began integration a short time later. H-IIA has a liftoff weight of 285,000 Kilograms standing 53 meters tall with a core diameter of 4 meters using a two-stage stack with two Solid Rocket Boosters attached to the first stage. The rocket is capable of delivering payloads of up to 11,000 Kilograms to Low Earth Orbit. The first stage of the H-IIA is 37.2 meters long and capable of holding about 100,000 Kilograms of cryogenic propellants, Liquid Oxygen and Liquid Hydrogen for consumption by the single LE-7A main engine. LE-7A is a staged combustion cycle engine delivering 1,087 Kilonewtons of thrust. Attached to the first stage are two SRB-A Solid Rocket Boosters - each 15.1 meters long and 2.5 meters in diameter weighing 77 metric tons. Each of the boosters burns 66,000kg of propellants during a 115-second burn. SRB-A3 delivers 2,305kN of thrust. Booster separation is triggered by pyrotechnics and the SRBs use struts to ensure a clean separation. The second stage of the H-IIA 202 is 9.2 meters long with a diameter of 4 meters. |
It also uses LOX and LH2 propellants, being filled with 16,600kg of cryogenics. One LE-5B engine powers the second stage providing a vacuum thrust of 137kN. The engine can make multiple ignitions to target a variety of orbits. A 4.07-meter fairing tops the stack and protects the payloads.
The ALOS-2 satellites and the four secondary payloads are also completing final inspections and processing at the launch site before being integrated on the payload dispenser and installed on the H-IIA launcher.
The ALOS-2 satellites and the four secondary payloads are also completing final inspections and processing at the launch site before being integrated on the payload dispenser and installed on the H-IIA launcher.