Recap of EOSS-17

Date:                      June 4,1994
Launch time:               15:59 UTC
Launch site:               Monument, Colorado
Launch site Coordinates:   Latitude    39 deg 02.67'N
                                      Longitude  104 deg 52.53'W
Burst Time:                17:20 UTC
Balloon Burst Altitude:    94,000 feet
Balloon Burst Coordinates: Latitude    39 deg 08.22'N
                                       Longitude  104 deg 40.08'W
Touchdown Time:        17:53 UTC
Landing Site Coordinates:  Latitude    39 deg 11.52'N
                                      Longitude  104 deg 25.99'W
 Ascent Rate:                1098 fpm
 Descent Rate:              1113 fpm

 Payload Frequencies:
 Telemetry:                 144.340 MHz
 ATV      :                 426.250 MHz
 Beacon   :                 147.555 MHz


The flight of EOSS 17 was another triumph in the many successful launches for Edge of Space Sciences Inc. (EOSS). This flight's success was due to the tremendous teamwork of personnel at the ground station and out in the field.

The flight started promptly at 16:00 UTC from the NAVSYS INC. facility in Monument Colorado. The weather was excellent.

During the flight a barometric switch was tested. The purpose of the switch is to add a safety to the cut down circuit. The switch is designed to be open below and closed above a certain altitude. The experiment was deemed a success. The switch closed at 26,000 feet on ascent and opened on descent at 25,000 feet. This switch will be tested on future flights to determine the repeatability of the results.

APRS performed perfectly during the flight. The spectators were treated to the "realtime" updates of the balloon's position. 

The ATV video was P-5 during most of the flight.  We captured the bursting of the balloon, via the onboard ATV camera, on video tape. Dave Radomski, KT0H, video taped the balloon burst with a camcorder from his ground position out in the field. During the descent of the payload the ATV antenna was forcefully separated from its short coax lead and plummeted to the ground from about 70,000 feet; location unknown. We should have some more dramatic video to add to the EOSS library.

The tracking and recovery team did another great job. During the descent phase of the flight at about 44,000 feet, Loran-C lost its lock and did not regain it for the remainder of the flight. From this point on, the ground station was unable to assist in determining the payload's location other than providing an RDF fix. Thanks to the expert assistance from our tracking and recovering team, the balloon's position was followed using the more traditional direction finding techniques we employ on every flight.

The tracking and recovery team consisted of:

  • Paul Ternlund WB3JZV (computerized triangulation)
  • Marty Griffin WA0GEH (field coordinator/net control)
  • Ed Boyer N0MHU air mobile
  • Richard Shaw WB5YOE
  • Tom Isenberg N0KSR
  • Bob Ragain WB4ETT        ----\
  • Colleen Ragain N0QGH          --- Family affair!
  • Dawn Ragain N0QCW      ----/
  • Greg Burnett K0ELM
  • Greg DeWit N0JMH
  • Larry Cerney N0STZ
  • Roger Smith N0LEQ
  • Bill Andrus N0EUL
  • Rick von Glahn N0KKZ (back at the ground station)

EOSS would like to extend its sincere thanks to the members and regular users of the 146.970 MHz Pikes Peak FM Association's fantastic repeater. Having a repeater on a 14,000 foot tall tower (@8,000 above surrounding terrain) is a real help.  Balloon flights really tie up the frequency and the patience of their regular users is greatly appreciated.

Thanks to all the folks at NAVSYS for their great hospitality and the use of there facility, and to all the folks out in the field and all who helped set up and tear down the ground station.

The original plan for this flight called for a test of the "Shuttle II" controller. However, unanticipated assistance from Murphy introduced a few problems and we had to abort that test. Shuttle II should be ready soon and we will announce its maiden flight when we have a firm schedule set.