FLIGHT SYNOPSIS OF EOSS-21

LAUNCH DATE: Feb 4, 1995
LAUNCH SITE: Jim White's Place
LAUNCH SITE COORDINATES: 39.5166 deg North, 104.5920 deg West
LAUNCH TIME : 15:45 UTC

Burst Time: 16:55 UTC
Burst Altitude: 98,676

Landing Site Coordinates: 38.77233 deg North, 103.84533 deg West
LOS at Ground station: 17:31 UTC



Shuttle II FREQUENCIES:

  • Telemetry: 144.340 MHz
  • Beacon: 147.555
  • ATV: 426.250

Foxhunters:

  • Pikes Peak FM Association Repeaters 448.450 MHz
  • Colorado Repeater Association Repeaters 447.150 MHz

------------------------------
FLIGHT LOG:
------------------------------
After suffering through an ordeal by atmosphere last flight, we used this flight to re-qualify the Shuttle II for use in experimental flight.

Our first problem of the day arose immediately. There were no winds aloft for Denver in the RAOB file on Weatherbank. However, there was a report from Grand Junction. I usually use these winds as a corroborative data set and this time around we had to rely on them exclusively. Another problem with those winds, no data above 54,000 feet. Using data from the previous evening for the 60,000 feet and above winds we estimated the balloon would fly 65 to 70 statute miles on a course of 130 degrees (approximately). In fact, the balloon flew 65 miles on a course of 142 degrees. Hey everyone's entitled to a little luck.

The ground station was having problems commanding the payload prior to lift off. This necessitated a swap of radios at the command position and an abandonment of APRS monitoring at the ground station. The flight was late getting off the ground for this reason.

After the swap, filling the balloon and setting up the payload train proceeded without incident. However, the winds were picking up steadily throughout the setup.

At 15:45 UTC the balloon was released.

Initially all systems were working fine.

As the balloon rose into the sky, the ATV camera fogged up causing less (much less) than perfect video. This is a recurring problem since we switched to the color camera. A few experiments were done to determine the location of the fogging. It is hoped that we can correct this for the next flight.

Occasionally we were unable to command the payload from the ground station. However, a mobile rig in a nearby car served as backup and seemed to have no problems in this regard. We're a little mystified about this as the ground station should have a much better signal into the payload thru our beams. A link analysis is planned to determine the purity of DTMF tones, and the bandwidth of the receiver. More about that later probably.

We lost our ATV antenna on descent. This time the antenna did not detach, just some serious coax degradation that killed any output.

GPS worked GREAT most of the time. We got all of our telemetry from ground to burst. However, we did have some problems on the descent phase. It's thought that some test commands that were sent to the payload intended for other experiments may have had an unintended side effect on the GPS state (navigation, acquisition, loading ephemeris>. This will be looked into also.

Jim White's location was also fantastic. His QTH is almost the highest house in the area, and it certainly offered EOSS an ideal location for a launch. There was quite a crowd there too. Thanks to you Jim and to Diane (his wife) also for putting up with a lot of crazy folks at ungodly early hours!

Files