Two drop tests at ESRANGE base - 5/24/2011
Kiruna, Sweden.- 2011 will be a really busy year for the Swedish stratospheric balloon launch base of ESRANGE in Kiruna. Just a few days after the closing of an intesive launch campaign and before the start of another one in next June, a complex experiment was performed at the facility, involving two drop test of aerodinamical shaped rocket-like models from the stratosphere.
The tests were managed by the Aviation Program Group's Supersonic Transport Team of JAXA, the Japan Aerospace Exploration Agency under the umbrella of a project called D-SEND, acronym for "Drop test for Simplified Evaluation of Nonsymmetrically Distributed sonic boom". The main goal of the effort is to acquire data on the behaviour of two different bodies that are droped in free fall 10 seconds apart, from a height of 30 km. The waves of the sonic boom generated by each body in it's falling, are detected by several sensors located in the ground near the drop zone, while other sensors are placed 1000 meters above ground, anchored to tethered balloons. At left we can see a picture of the two rocket-like bodies being readied for the first launch at ESRANGE. One of the test probes is the NWM (N-Wave Model), which generates the pressure signature of an "N" wave -the shorter in the picture-, and the other is the LBM (Low-Boom Model), which generates the pressure signature of a low-boom wave.
The team from JAXA, arrived to Esrange in late March and was since preparing the three test bodies and associated systems to be used. The first test -which was succesful- took place on May 7. The balloon after ascending, headed northeast of the launch base to a remote place inside the no-fly zone of the ESRANGE testing complex, where the drop was done from 21 km.
The second drop test -that involved a similar configuration of two falling bodies but from 27 km- was performed nine days later on May 16, with the same succesful result.
According to the SSC's press release, the Japanese team managed by Dr. Kenji Yoshida, was very pleased with the preliminary results of both tests and with the fact that the entire mission went according to plan, being acomplished under a flight window of four weeks. This is the first time that two heavy models are droped in quick succession, from a single balloon.
Besides the smooth launch and recovery service, another contribution of SSC to the effort was the construction of the gondola that carried the two models attached to the balloon and part of the electronics system that linked the probes to JAXA's telemetry systems.
More information on the test and preliminary data is available from a press release that JAXA published at their website.
New building inaugurated
Due to increased demand for launch services in last years, SSC decided a year ago, to start the construction of another building for integration of rocket and balloon payloads. The brand new space is located close to the existing buildings in the balloon launch pad area and counts with an area of 795 square meters (image at left). It was officially inaugurated the past week with a small party attended by SSC authorities as well staff of JAXA, NASA and the scientific teams that will participate on the two ongoing campaigns of transatlantic flights from Sweden to Canada (LEE, AESOP and HIWIND missions) and POGOLITE the instrument that will make it's stratospheric debut next June.
More details and images are available in the SSC's press release published on May 19.
CNES balloon campaign ends - 5/2/2011
Kiruna, Sweden.- Several balloon missions were performed in the last weeks of April to complete the launch campaign being carried out by the balloon division of the French Space Agency CNES. As usual, all the balloons departed from the stratospheric balloon launch base of SSC (former Swedish Space Agency) outside Kiruna, near the Arctic Polar Circle in Sweden.
The following is a summary of the missions performed on those last days.
On April 7 was launched the DUSTER (Dust in the Upper Stratosphere Tracking Experiment and Return) payload which after a flight of five hours landed NE of Porsi, Sweden. The aim of the flight was to obtain aerosol samples where abundance, size distribution, composition and mineralogy will be measured for each class of materials collected. Then, after an "impasse" of near 10 days activity resumed on April 19 with the launch of the SSTD payload including a star tracker sensor. After a flight of almost four hours it landed in the northern part of Sweden.
The next day took place the flight of SPIRALE (Spectroscopie Infra-Rouge par Absorption de Laser Embarqué) a tactical mission to track a large tropical intrusion developing above Scandinavia in the stratosphere from about 25 to 35 km height during that night. The mission obtained measurements during the slow commanded ascent that endured two and a half hours.
On April 23, was launched the LPMA (Limb Profile Monitor of the Atmosphere) payload which lasted in flight during four hours, almost the same flight time of the µRADIBAL (RADIomètre BALlon) mission that took place the next day. Finally, the last two missions were performed on April 28 and April 30 respectivelly. The first one was devoted to transport the SALOMON (Spectroscopie d'Absorption Lunaire pour l'Observation des Minoritaires Ozone et Nox) payload while the second had as main goal to perform a flight qualification of a new balloon called SF12. Both flights landed in a region southwest of Kiruna.
As a balance we will point that the first phase of the campaign started on 23 January with the first mission performed on 15 February, and a total of four flights performed. After a break of several weeks it resumed on April when 9 more balloons were successfully launched, whit the last one taking place on the night between April 30th and May 1st.