Announcement of EOSS-46

note: The original announcement for this flight was lost. This is a recreation compiled on 18-March-2005. the recreation was prompted by the recent submission by Marty Griffin, WA0GEH, of documents pertaining to the flight.

LAUNCH DATE: December 16, 2000, Rain date is December 17, 2000
LAUNCH TIME: 15:00 UTC - 09:00 MST
LAUNCH SITE: Windsor, Colorado (Gene Fatton's Ranch - Here's a Map

  • Directions: Leave Denver Colorado on I-25 north bound. Proceed to the Windsor exit (Exit Number 262). Proceed East on State Road 392 approximately 1.3 miles to county road 3. Take county road 3 south a few hundred yards. The launch site will be on the east side of the road. Numerous vehicles with antennae will undoubtedly mark the spot.


  • 40.4744 Degrees N. Latitude
  • -104.9628 Degrees W. Longitude


  • Between 80 degrees and 145 degrees azimuth


Preflight Foxhunter Net:

  • 147.225 MHz Colorado Repeater Association
  • 8:00PM the preceding night

Launch Site:

  • Simplex 146.550 MHz


  • 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.

Cross-Band Rptr:

  • Input 445.975
  • output 147.555

APRS Output:

  • 147.555 MHz
  • Output of Crossband Repeater


  • 426.250 MHz.

Tracking Team:

  • 449.450 MHz Rocky Mountain Radio League (RMRL) (pending approval)
  • 146.58 MHz Simplex Field Frequency

HF Net:

  • 7.235 MHz, net control pending


  • Pioneer Astronautics, Dr. Robert Zubrin, Dean Spieth, �Mars Micro Balloon Probe�.


  • This is the fourth 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.
  • Additionally, a 1200 gram �Grape� drag balloon will fly to help stabilize the payload on decent while deploying the micro balloon. This experimental drag balloon concept will be deployed on Mars missions if successful.
  • Detailed information and project proposals can be found on the EOSS web site,


  • None for this flight.


  • None


  • The RMRL cross-band repeater will be deployed. QSL cards will be issued for successful contacts through the repeater.


  • The packet callsign will be: W0WYX


Shuttle Generated Automatic Position Reporting System (APRS):

Some of the APRS systems aboard EOSS payloads will act as digipeaters. However, we request that only the Chase team use this system in order to minimize the disruption to the packet telemetry. Chase team APRS info is used to assist in coordinating placement of the various DF teams.

Please disable your beacons on the EOSS packet frequencies, as that will minimize interference to other stations in your area trying to copy telemetry. Of course, if we are on the National APRS frequency, you should continue to beacon out your data as usual. WE do NOT want to interfere with 144.390 MHz traffic other than to add our balloon's location.


ATV is transmitted on 426.250 MHz. This is equivalent to cable channel 58. If you have a high gain 70 centimeter antenna, it may be possible to view the video on a normal TV. However, we only transmit 1 watt so you will need a very high gain antenna for this frequency.

Marty's Email

I include this email as it is the original preface to the above announcement as it was distributed to various news groups, and email lists.

-----Original Message-----
From: Marty Griffin
Sent: Sunday, December 10, 2000 1:47 PM
To: Eoss_Lt; Eoss
Cc: EOSS - George Reidmuller
Subject: EOSS #46 Flight Announcement

Flight Announcement for EOSS #46

EOSS #46 is on schedule and will launch at 9:00 am MST, December 16, 2000 (rain date December 17, 2000). The launch site is at Gene Fatton�s Ranch at Windsor, Colorado. The beautiful control room (AKA sunroom) will once again provide a fabulous mission support facility. EOSS asks visitors to this
room to remove their shoes so we do not wear out or soil our welcome.

Listen for the beacon on 147.555 and look for ATV on 426.25 MHz. The flight should reach 100,000 ft. and the beacons should be heard in a 400 mile radius.

The RMRL Cross-band repeater (445.975/147.555) will provide a wide range of operational fun. QSL cards will be sent to stations making contacts through the RMRL repeater thanks to Mark Patton (K0YG).

This flight is on behalf of our ongoing Mars Micro Balloon Probe sponsored by Pioneer Astronautics. The objective will be to deploy a micro balloon on decent as well as to minimize �Post-Burst Chaos� on decent using a 1200 gram balloon (�grape�) as a stabilizer.

This fight will use two helium balloons. The main lift balloon will be a 3000 gram balloon and will be cut away at 100,000+ feet. The second balloon or �grape� will be a 1200 gram drag balloon used to stabilize the payload on decent. It will be cut away after the Mars micro balloon is deployed. If successful, the drag balloon will be used in future Mars balloon deployments.

Friday night, December 15, Marty, WA0GEH will conduct the tracking and recovery net on 147.225, 8:00 MST. Logistics for the tracking and recovery operation will be discussed. Please plan to listen in or, if you are interested, joining the effort.

Tracking and Recovery People: Please advise if you can support this flight to Marty Griffin, or 303-470-5471. This will save a phone call, thanks.

The Tracking and Recovery net will be on 448.450 MHz Saturday, December 16.
Starting about 7:00 am logistic traffic will start to flow. This will be become a DIRECTED net, all traffic for the recovery effort will be directed through Marty, WA0GEH.

This flight was delayed. Here is that announcement:

-----Original Message-----
From: Marty Griffin
Sent: Thursday, December 14, 2000 2:14 PM
Subject: EOSS #46 - Flight Rescheduled to 1/13/01

Hello Everyone,

EOSS #46, currently scheduled to launch December 16, 2001 has been rescheduled to January 13, 2001 due to forecasted weather issues. The current and forecasted outrageous winds aloft data assures the flight will travel 150 - 225 miles, well out of range of our ground control stations. This range will not allow control stations to conduct, monitor and control the airborne experiments

Additionally, forecasted ground winds are well above the EOSS maximum wind standards for a flight with a very complex, multiple-balloon flight string.

For all of you who were planning to watch this flight as well as participate on the crossband repeater, be sure to mark your calendars for January 13.

We welcome any high school science students to join us on this flight.
Please contact Marty Griffin.

Larry, K0ANI, will you please forward this message to the ham balloon groups you contacted earlier?

Rick, N0KKZ, will you please adjust the web page at to reflect this announcement?

Mike, W5VSI, will you contact the FAA and reschedule?

Marty, WA0GEH, has contacted Gene Fatton and rescheduled the launch site.
He has agreed to the January 13 date.


Marty Griffin, WA0GEH