EOSS-301 COSGC Summer Flight Recap

EOSS-301 launched as a single 3000g balloon from Deer Trail Colorado for the University of Colorado Space Grant Consortium (UCSGC).  The balloon carried 8 student experiments to an altitude of 98,457 ft, and was recovered south of Calhan Colorado.

12:46:04 UTC     Launch                39.608333, -104.042221                 4,948’

14:39:42 UTC     Burst                   39.120701, -104.368077                98,457’

15:22:00 UTC     Landed                38.838758, -104.315802                 6,126’


14:48:57 UTC     Lowest Outside Temperature: -76.3 F  at 55,800’ on decent


Mileage reimbursement can be found here:https://www.eoss.org/node/3795.


Original Announcement: 

Launch Site Changed to Deer Trail. New Payload plans postedNote new net frequency and time below.1x 3000g balloon or two 1500g

Event Date: 
Saturday, August 1, 2020 (All day)
Flight Coordinator: 
Launch Site: 
Punkin Center: X=60, Y=40 Test: N39.000 W104.00 Ans: X=44.0 y=50.2


One 3000g balloon, or two 1500g balloons if weather precludes an exempt launch.

EOSS-301 Lite Payload Plan Rev C

EOSS-302 Lite Payload Plan Rev C

Balloon Type: 
3000g latex
12 ft Rocketman Orange/Green
145.645KC0D-14APRS/Release/DFTop of record; Release Adam
144.340AE0SS-12APRS / Digi Slotted 27/57 Digi EOSSA
145.765KC0D-1APRS/Release/DFTop of Record, Release Baker
144.34 K0SCC-14APRS/DigiSlotted 20/50 Digi EOSSD
144.905KC0D-3APRS/Release/DFUnder Qual, Tethered Release Charlie (300 Heavy only)

EOSS Preflight Net @ 7 PM MDT preceding night:

        •  Preflight Net  449.225 MHz, 141.3 HzPL, RM HAM RMHAM Repeater, See KC0L for Echolink instructions if required, NET AT 1900 hr (Moved Earlier).  See July 2020 QST for EchoLink Tutorial, page 70. Contact John, KC0L for a virtual tutorial on getting started with EchoLink.

        • 146.940 MHz (-600 KHz Offset, 103.5 Hz Tone) RMRL Repeater if the RMHAM machine is down

        • 146.640 MHz (-600 KHz Offset, 100.0 Hz Tone) DRL Repeater will serve as a backup to the backup repeater

Launch Site:
        • 446.050 MHz Simplex 
        (Note that some radios assume these are repeater frequencies and attempt to put a 5 MHz offset in the transmit frequency automatically)

Track & Recovery Operations:

        • 448.450 MHz (-5 MHz Offset, 100.0 Hz Tone) PPFMA repeater.

        Simplex Frequencies:
        • 446.100 MHz EOSS 301 Field Simplex
        • 446.150 MHz EOSS 302 Field Simplex
        • 446.200 MHz Optional Field Simplex
        • 446.275 MHz Car to Car drive out Simplex
        (Note that some radios assume these are repeater frequencies and attempt to put a 5 MHz offset in the transmit frequency automatically)

We will be using the DMR South zone.  Here's what to do to get on that zone:

1. Select “DMR South” zone

 2.  Select “Almagre RK MTN”  which is “wide” on the RMHAM system lighting up 33 sites in three states.



Tactical Calls: 
TacticalCall SignNameNotes
AlphaWA0GEH. KC0DMarty. Mark
BravoW9CN, N0JPSMike, John
CharlieK0BRA, N0RPFDoug, RobFrom Launch Site
GolfK0JWB, N0NKKJohn, Nancy
Ground StationN2XGL, Jeff, Randy
HotelKB0YRZ, K0LOBChris, Jim
IndiaKA0ZFI, KB0UBZAnn, Ben
YankeeKE0YALBrad M