Recap of EOSS-41

Flight Delayed 1 day due to Weather

LAUNCH DATE: June 18, 2000
LAUNCH TIME: 15:23 UTC - 09:23 MDT
LAUNCH SITE: Pikes Peak Radio Control Club Airport (Here's a Map.

  • 38 deg 57' 17.65" North Latitude
  • 104 deg 30' 04.43 West Longitude


  • 39.1667� North Latitude
  • 103.438� West Longitude 
  • Bearing: 75.3� True
  • Range: 58.8 Mi.


  • 18:45 UTC 12:45 Local
  • Flight duration - 3hr 22 minutes (very slow ascent rate of @ 700 fpm)

Prediction Recap: 

Launch Site - Model Airport
Launch Point: 38.9549� lat.   -104.5012� long.
Ascent Rate: 1004 feet per minute
Descent Rate: 1230 feet per minute
Altitude: 5500 feet
VOR Station - Black Forrest (BRK)
Latitude: 38.9417� lat.
Longitude: -104.6333� long.
Magnetic Offset: -10.3� from True Degrees
Predicted Landing Site
Landing Point: 38.988� lat.  -103.6865� long.
Altitude: 4199 feet
Flight Time: 120 Minutes
Bearing: 86.8� True
Range: 43.8 Mi.
Actual Landing Site
Landing Point: 39.1667� lat.  -103.438� long.
Bearing: 75.3� True
Range: 58.8 Mi.
Difference from Predicted to Actual Landing Site
Bearing: 47.1� True
Range: 18.2 Mi.

PRIMARY FLIGHT EXPERIMENT: Second test of new �Shuttle� built by UCCS. Test of shuttle�s flight worthiness, downlink telemetry, system control and ATV. The ATV will be used to monitor and confirm the success of the secondary experiment.

PRIMARY PROJECT INTEGRATOR: Colorado Springs (UCCS), Dr. Chuck Fosha, Brett Allard, and a host of aerospace students

SECONDARY INTEGRATOR: Pioneer Astronautics, Dr. Robert Zubrin, Dean Spieth, �Mars Micro Balloon Probe�.

SECONDARY EXPERIMENT: This is the first of many planned EOSS flights for the �Mars Micro Balloon Probe� which will place a series of balloons in the Martian atmosphere. The objective of this flight are to test and develop inflatable gases from compounds that are normally liquids at Standard Temperature and Pressure (STP). The Mars surface pressure is simulated at 100,000 feet above sea level, thus the experiment on an EOSS balloon. This experiment will attempt to inflate balloons using various compounds. This will also permit a test of the deployment canisters required on Mars.


  • Telemetry:
    • 144.340 MHz FM (1 Watt output) - The Packet telemetry stream is in ax.25 format at 1200 baud and is readable in plain English for the most part. Included in each telemetry frame is an APRS position string (APRS users see note below). Every few minutes a CW ID is transmitted on this frequency. This is the UCCS Shuttle, not an EOSS Shuttle II. So telemetry will differ slightly from what is normally seen.
  • ATV: (see notes)
    • UCCS Shuttle - 426.250 MHz AM (1 Watt output) - NTSC video
  • Cross-Band Repeater: (see notes)
    • 445.975 (input)
    • 147.555 (output)
  • Beacon (see notes)
    • 147.530 MHz (UCCS tracking support) CW Id only (I think)
  • APRS:
    • 147.555 MHz on the xband repeater output, there will be an APRS packet burst. See notes below.
  • Foxhunters:
    • 448.450 MHz Pikes Peak FM Association Repeater (approval received 5/30/00)
    • 146.580 MHz Simplex Field Frequency
  • HF Net:
    • 7.235 MHz -  net control Mary Francis Bartels, KI0DZ

EOSS-41 Flight Track

Map by Street Atlas V 7.0

Balloon Track by APRS-Plus

Predicted Track by Balloon Track

Black Line the balloon track
Blue Dots, the predicted ascent
Red Dots the predicted descent

The Landing Site

Dan, N0PUF, surveys the leftovers (photo by K0ANI)



Apparently there was a dramatic reduction in output on the ATV system. The video could be seen P1 at the launch site briefly, but once the payload departed the immediate launch site area, the signal was lost.

Cross Band Repeater and Automatic Position Reporting System (APRS):

Many thanks go to Bob, N0TI, who shoehorned the Bob-E box code into the RMRL crossband repeater. More thanks go to Mike W5VSI who mashed the hardware into the repeater enclosure.

The Cross Band Repeater functioned flawlessly throughout the flight. The repeater was heard as far north as Laramie Wyoming by Norm.

The packet callsign was: W0WYX

In order to minimize possible interference with the tracking and recovery team  and other hams in your area, we requested you turn off the position beacons at your APRS station on 147.555 MHz. Everyone evidently complied as there was no detected interference. Thanks.


The beacon was not heard by the tracking and recovery team.

The UCCS Payload took a beating on landing (photo by K0ANI)

Telemetry Files: 

Text File

Spread Sheet

Street Atlas overlay

Zip File - This file contains a Street Atlas V 7.0 map file and an APRS-Plus log file. A preliminary text log file is included. It contains the packet telemetry from the ground station with a few additional packets received by Mark Patton to fill in some gaps.

UCCS PowerPoint Recap

The UCCS Students presented an analysis of their package's performance. It is available in a PowerPoint animated presentation or as a PDF file for those of you without PowerPoint.