EOSS 338 CU Boulder - Gateway to Space - Recap

A single 3000g balloon was launched on Sunday April 16, 2023 from Deer Trail Colorado. The balloon carried 9 Gateway to Space BalloonSats to an altitude of approximately 104,000 feet. The balloon landed southeast of Arriba CO.

MIleage link for club members is here.


Original Announcement: 

04-13-2023Note: Because of inclement weather, the flight has been changed to Sunday 4/16. 0700 from Deer Trail. Directions to Deer Trail are posted here

  • 04-05-2023Payload Plans Rev A posted
  • 04-10-2023Payload Plans Rev B posted
  • 04-10-2023Flight Day Operational Frequencies updated
  • 04-11-2023Payload Plans Rev C & Grid posted
  • 04-15-2023Payload Plans Rev D posted

This is one 3000g balloon or two 1500g balloons flying nine BalloonSat payloads from University of Colorado - Boulder's Gateway to Space course.

Flight predictions can be found here

If the cloud cover prevents flying a non-exempt balloon the payloads will be split into two exempt balloons as follows:


Event Date: 
Saturday, April 15, 2023 - 07:00 to 23:45
Flight Coordinator: 
Launch Site: 
Last Chance: X 30, Y 50 Grid Test: N 40.000 • W 103.000  X 61.3 Y 67.9


Balloon Type: 
3000g Totex
12 ft Rocketman
144.340AE0SS-12APRS/Digi EOSSATime slotted at 0:27 and 0:57
144.905KC0D-14DF Wireless Release Adam
Payload Plan: 

EOSS Preflight Net @ 7 PM Mountain Time the preceding night:

The preflight net is hosted on the Fun Machine linked system https://www.we0fun.com/  

EchoLink *CANONCTY* conference and on the TGIF DMR Network Node: 1997 Talkgroup 815

Denver area Frequencies: 

    • 449.225 MHz (-5 MHz Offset, 141.3 Hz CTCSS) Mt Thorodin
    • 448.150 MHz (-5 MHz Offset, 141.3 Hz CTCSS) DIA
    • 449.975 Mhz (-5 MHz Offset, 100 Hz CTCSS) Westcreek
    • 447.525 MHz (-5 MHz Offset, 146.2 Hz CTCSS) Devils Head   

Back up Pre Flight Net Frequincies

        • 146.940 MHz (-600 KHz Offset, 103.5 Hz CTCSS) Rocky Mountain Radio League (RMRL) Repeater if the RMHAM machine is down
        • 146.640 MHz (-600 KHz Offset, 100.0 Hz CTCSS) Denver Radio League (DRL) Repeater will serve as a backup to the backup repeater


EOSS Operational Communications    

*     Primary SkyHub repeater North         K1DUN        449.450-    PL 103.5

*     SkyHub linked repeater (Limon)          KDØOXW       447.650-    PL 103.5

*     SkyHub linked repeater (Hugo)           KDØOXW       447.425-    PL 103.5

       SkyHub linked repeater (Straton)           AD5MQ       146.895-    PL 114.8

*     APRS Frequency & Path:                                     144.340       EOSSA

*     Field Simplex EOSS-338:                                  446.100

*     Field Simplex EOSS-339:                                      446.150

*     Car to car drive out Simplex:                                446.275

*     Launch site, Ground Simplex:              AEØSS        446.050

*     DMR Rocky Mountain Wide                  RMHA       Talk Group 700

2M Direction Finding Frequencies:

  • 144.340
  • 144.905
Tactical Calls: 
TacticalCall SignNameNotes
AlphaWAØGEH, KCØDMarty Mark
BravoNØNDM, W0CBHLarry, Benjie, 2 grandkids
CharlieKCØRPS, NØNFWJim, George
DeltaKØSCC, KE0BMVStephen. Parker
EchoNØNKKNancy Launch Team
Ground StationN2XGL, K5JKJeff, Tom, Randy, Russ
IndiaKØBRA. KE0UWCDoug, Glenn,
TangoKCØLJohn, Shane
TR Breakfast: 
iHop, Limon 0600