A Japanese two stage sounding rocket at its 2nd appearance - An interesting object for sport scale. The SS-520 is a two-stage rocket, the first stage of which comes from the main booster of the S-520, and has a capability for launching a 140 kg payload to an altitude of about 1,000 km.
The SS-520 aims at reaching 1,000 km altitude, and at the same time, carrying out technological experiments concerning the development of a mini-satellite launch vehicle by adding the third stage atop. The first stage is stabilized aerodynamically by use of tail fins like the S-520.
As the second stage is heavier than the head of S-520, the aerodynamic margin is secured more than ever. The whole motor case of the second stage is made of CFRP. The spin generated in the first stage is succeeded by the second stage, and it is utilized in the Rhumb-line control and spin stabilization.
The SS-520-2 rocket was launched at 6:16 PM (local Japan time) on December 4, 2000, from SvalRak (Ny Olsen), Norway, at an angle of elevation 86°, azimuth 192°. The rocket launch was normal, ignition occurred on schedule at 67 seconds for the first stage, 69 seconds for the second stage, and it reached its summit of 1,040km at about 600 seconds, before splashdown at about 1,100 seconds. All telemetry and onboard instruments functioned smoothly, the boom and antenna deployed, and the high-voltage power supply to the various sensors went according to schedule. Telemetry reception was conducted in three locations, at Ny Olsen, Longyearbyen, and Andoya, and excellent data were acquired. As for the rocket launch, by monitoring EISCAT radar data in real-time and solar wind plasma and interplanetary magnetic fields by ACE satellite, it was confirmed that the rocket actually flew above the artic cusp. The scheduled observation from the ground was impossible due to the weather, but from the observation data of the onboard instruments it was deduced that the vehicle flew above the artic cusp. Detailed analysis is to be performed upon the ISAS teams return to Japan.
The main objective is to study ion heating and acceleration processes and associated ion out flowing phenomena occurring in altitudes of ~1,000 km above the dayside cusp/cleft region. The outflow of ionospheric ions, especially from the dayside cusp/cleft region, is an important source of magnetospheric plasma. Much of the ion outflow is caused by ion heating in the perpendicular direction to the geomagnetic field.
A number of physical mechanisms have been proposed, but most are hypothetical, poorly understood, or simply conjecture. The goal of the present experiment is to put these mechanisms into perspective.
For this purpose, the SS-520-2 rocket is designed to carry nine instruments:
- TSA - Thermal and Suprathermal ion Analyzer
- TECHS - Thermal Electron Capped Hemispherical Spectrometer
- XUV - XUV 83.4-nm photometer for oxygen ions
- ESA - Electron Spectrum Analyzer
- ISA - Ion Spectrum Analyzer
- PWA - Plasma Wave Analyzer
- NEI - Impedance probe for electron density
- TEL - Electron temperature probe
- MGF - Magnetic Field Instrument
Sport Scale and the SS-520
The SS-520 series makes a fine entry for sport scale or even scale model rockets for beginners as well for intermediates. The shape of the rocket is very simple. Basically we are talking 4 fins and a nose cone - but no conical transitions or other hard to create shapes. And still, there are enough challenging details to add to get more craftsmanship points and even mission points.
It is relatively easy to generate a file to make water transfer decals (www.tangopapadecals.com) simulating all those Van Allen screws etc. or the umbilical plug markings on the payload section. The leading edge of the fins is very unique and could be simulated with decals too!! You decide the degree of complexity you want to exhibit. [I have created a set of water transfer decals for the SS-520-1 which is available as pdf-file upon request.] Or just think about the cork wrap of the 2nd stage.
A longer airframe coupler wrapped with that cork material you can get at home improvement stores might mimic that feature sufficiently. Or you scan a piece of cork, scale it down an print it on white decal vinyl and the apply it on the airframe. There are definitely different way to do it.
There is a realistic chance to get some mission points too.I built my first model of the SS-520-1 in a way that it was spinning to contribute to the spin stabilization of the 2nd stage. The more brave modeler will have an active 2nd stage using a timer for staging and ignition. You might consider flipping fins for the very short second stage as spin stabilization alone might not work in a small model.
Safety first! If you fly a magnetic apogee detector you should get some more mission points there was a Magnetic Field Instrument on board . . .
This article originally appeared in UROC's Ballistic Beehive in 2004