Flight Announcement for EOSS-174

Flight Coordinator: Jim Langsted - KC0RPS
LAUNCH DATE: April 14th, 2012 (wx delay +1 day)
LAUNCH TIMES: 07:10 am MDT (13:10 UTC)
LAUNCH SITE: Windsor, CO (Click Here for directions)

FAA Waivers for 2012

EOSS Flight Day Frequencies:

Tracking and Recovery Frequencies

  • Preflight Net:
    • 147.225 MHz 8 pm MDT preceding night
    • 146.640 MHz will serve as a backup frequency
  • Tracking and Recovery Operations
    • Repeaters 
      • South End of Recovery
      • North End of Recovery (Wyoming)
        • 146.775 MHz (114.8 Hz Tone) Cneyenne (Linked to Albin)
        • 147.165 MHz (114.8 Hz Tone) Albin (Linked to Cheyenne)
    • Field Simplex Frequencies  
      • 446.100 MHz simplex for field recovery operations
        • Note: Some radios insist on incorrectly placing a negative 5 MHz offset when selecting frequencies from the simplex portion of the 70 CM band. Check your radio and if this is the case. Consider programming in this simplex frequency to a memory channel as some radios have demonstrated the annoying habit of re-inserting the offset if you momentarily shift to a repeater then return to the simplex freq. Check the operation of your radio on this simplex freq to be ready for however your radio behaves.
      • 146.550 MHz Backup field simplex
    • Repeater Coverage Pages - Listings of all repeaters available in the expected flight areas.
    • There may be FRS operations see THIS PAGE for a list of channel numbers and their associated UHF Frequencies.
    • HF (possible as of this update)
      • 3.810 MHz LSB
      • 7.235 MHz LSB
  • Launch Site Simplex
    • 146.550 MHz


EOSS-174 Balloon Payload Frequencies

  • Beacons
    • 147.555 MHz
      • CW ID: AE0SS
  • 144.340 MHz
    • ID: AE�SS-11
    • DIGI: EOSS
    • Node: BALNOD
    • APRS Time Slotted Every 30 seconds at 0:00 and 0:30
      • power up at 58 seconds past the GPS minute to properly slot telemetry
    • Telemetry once a minute
    • Sample Data


Video Might Be available, check http://www.eoss.tv

Various Online Live Tracking Pages

Flight Systems:  


Balloon Manufacturer Totex
Balloon Type latex
Balloon Size 3000 g
Neck Load 22.1 lbs.
Neck Lift 26.4 lbs.
Ascent Rate 1329 fpm estimated
Descent Rate 950 fpm estimated
Parachute 10 ft.
Peak Altitude 97,000 ft. estimated
Launch Conditions determined at launch

Payload Configuration: 

Payload Experiment Designer

SGC Demosats, Metro State

Experimenters are welcome to submit websites for linking or overviews which I will post on a page on the EOSS website.

Internet Gateway Stations:

Future I-Gaters:

EOSS is always in need of I-Gate stations. Check out the EOSS I-Gate page for information on how to participate and why we need you.

Current I-Gate Station:

If you are present at your iGate during the flight try and monitor the tracking and recovery frequency. The ground station likes to check the frequency prior to launch to find out if any stations are out there ready to igate the traffic onto the net for the FAA to monitor.

The prediction program used to determine the track of the balloon prior to flight can now output a prediction for the Rise, Closest Approach, and Set of the balloon for each of your stations. I have posted a prediction page for stations that I have been able to discover geographic coordinates. See the I-Gate prediction page for an example. The page will not be updated daily, however, it will be updated the evening prior to flight for I-gate planning purposes.

I have often been asked by iGaters when they should expect to either start receiving signals (AOS) or expect to see those signals disappear (LOS). This prediction page should answer all those questions for you.

Your Log Files

Our technical committee members would also request you open a log file and record all the packets you hear and forward onto APRS-IS. Whenever there is a technical failure of a package it is always helpful to have the most complete dataset possible to attempt to determine the cause of failure and possible fixes. After a flight send your data files to me (webmaster) and I will distribute them to the appropriate payload builders. They appreciate these logs even if all goes fine during a flight.

Tracking and Recovery 




It looks like we will be heading to Wyoming for this recovery.  Bring your passports!

Please note the Cheyenne and Albin repeater frequencies in the Cheyenne area for our recovery frequencies. 

We will formally, under net control, move to repeater frequencies

Fill up with gas! Wear warm clothes and good boots.  Bring tow ropes!

Only one, well-laden balloon this flight.

Greet Lia Mathews, the new coordinator for Colorado Space Grant.

A Glider with cell-phone messaging connections will be released 50 minutes into the flight.  Trackers may
try recovery efforts after our payload is recovered.  More later.




Grid X

Grid Y

West Intersection of CR 71 and CR 14 80 10
Test Coordinates   41.25� N  x  -104.5� W 37.3 54.1



Tactical Call Signs 





Alpha WA0GEH Marty Tracking and Recovery Coordinator
Bravo K0SCC Steve, Daryl and Parker Tracker, Driving Pro, Optical Tracking Asset, Food and Beverage
Charlie KC0RPS,  N0NFW, N0SSW  Jim, George, Harlan Flight Coordinator and Tracker
Delta KB0YRZ Chris Tracker
Echo none    
Fox KC0UUO, KD0QYY,N0IX, KD0RPF Rob and KJ, Doug, Alan Presidential Timber and First Lady and two Trackers
Golf N0NDM Larry Launch Coordinator, Tracker



Text Recaps


Launch Site


Recovery Site















EOSS-174, AE0SS-11


 Spread Sheets

  •  - airborne only Log ripped to spreadsheet format
  •  - KPC3 Telemetry log

Mapping Files