EOSS-378 Great Plains Superlaunch - Recap

KCØRPS's picture
Submitted by KCØRPS on Thu, 05/29/2025 - 09:21

GPSL launch scheduled for 7:30am in Buhler KS was put on a weather hold. We sat in the hotel breakfast area watching the rain falling sidewise because of high winds and looking for tornadoes.  We heard from Zack that the rain would stop and the skies would clear for an 1:00 pm launch.  We headed to Buhler around 11:30am to set up.EOSS launched one 2000g balloon with our scheduled payloads and added two additional beacons with Horus binary.  With help from other teams our balloon was up and away.  We stayed at the launch site and helped other teams launch. Flight predictions had the landing site about 5 miles from the launch so took our time packing up and chatting with other teams. The three tracker vehicles took off for the ralley point to await birst.  The balloon burst at about 89,165 ft/  Somehow we luckely landed in a muddy soybean field, corn fields on either side and trees across the back of the field.  We contacted the landowner and received approval to go in.  Mike and Chris donned their mud boots and took off to successfully recover our payloads.  

Recap Gallery: 
Original Announcement: 

This will be a 2000g balloon carrying EOSS beacons launched from Hutchinson Kansas as part of the Great Plains Superlaunch.

Predictions are shown at www.eoss.org/predict. Scroll to the correct date and launch site.

EOSS Planning:

Event Date: 
Saturday, June 14, 2025 - 00:00 to 23:45
Flight Coordinator: 
KCØD - Mark & K0NKK- Nancy
Launch Site: 
Hutchinson, KS
Flights: 

EOSS-378

Balloon Type: 
2000g
Parachute: 
12 ft Rocketman
Beacons: 
FrequencyCallsignTypeNotes
144.710KC0D-3APRS/ DF/Remote ReleaseTop
144.340KC0D-12APRS/DIGIBottom
Payload Plan: 
PDF icon EOSS-378 Rev C.pdf
FrequencyList: 

Preflight Net: 

    • Face to face at GPSL

Flight Day: 

    • 446.100 Simplex

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

Digital Mobile Radio (DMR):

The decision as to which talkgroup use will be made by the EOSS RF Coordinator on a per flight basis.

  • Rocky Mountain Wide Network – Talk Group 700 - Rocky Mountain Ham Radio has approval to the use "Wide" for flight operations.
  • Central Colorado Regional Network – Talk Group 720 - On occasion, EOSS may use the Central Colorado Regional Network (Talk Group 720).

2M Direction Finding Frequencies:

  • 144.340
  • 144.360
  • 144.905
  • 145.535
  • 145.645
  • 145.710
  • 145.765
Tactical Calls: 
Trackers
TacticalCall SignNameNotes
AlphaNØNDM, KBØYRZLarry, Chris
BravoNØMPM, WAØGEHMike, Marty
CharlieKCØRPS, KØNKKJim, Nancy
DeltaWBØURWJim
TR Breakfast: 
At the Holiday Inn Express Hutchinson