EOSS-391 - Qualification Flight - Recap

Nancy Koos K0NKK's picture
Submitted by Nancy Koos K0NKK on Wed, 02/25/2026 - 12:12

One 2,000g balloon was launched on March 21, 2026 from Deer Trail Colorado with EOSS qualifying payloads and a new ADS-B built by Metro State University - Denver.  The balloon was launched at 8:00am with the help of members from the Parker Radio Club. The balloon reached an altitude of 91,900 ft when it burst.  Trackers were talking to the landowner (just north/east of Arabia) as the parachute and payloads landed about 50 ft from the driveway they were standing in.  One of the easiest recoveries!

Recap Gallery: 
Original Announcement: 

One 1500g flight to qualify several new, updated, or repaired EOSS payloads

  Prediction: https://eoss.org/predict

Event Date: 
Saturday, March 21, 2026 - 08:00
Flight Coordinator: 
KC0D - Mark & K0NKK- Nancy
Launch Site: 
Deer Trail
Flights: 

EOSS 391 - Qual Flight

This flight is to qualify EOSS payloads that are new, have undergone repair, or have new firmware. This flight will consist of one 2000g balloon.

Balloon Type: 
2000 g
Parachute: 
12 ft
Beacons: 
FrequencyCallsignTypeNotes
145.645 MHzKC0D-2Top/Cutdown Paired with Release Baker
145.535 MHzAE0SS-2Discovery Qual Paired with Release Charlie
144.905 MHzAE0SS-1Atlantis LoRa QualPaired with Release David
144.340 MHzK0SCC-14Bottom QualSlot 00 & 30
144.340 MHzK0SCC-13Bottom QualSlot 13 & 43
Payload Plan: 
PDF icon EOSS-391 Payload Plan Rev E.pdf
FrequencyList: 

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   

Backup Pre-Flight Net Frequencies

        • 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 

Flight Day:
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:
        Repeaters:
        • 449.450 MHz (-5 MHz Offset, 103.5 Hz Tone) RMRL repeater

        Simplex Frequencies:
        • 446.100 MHz Balloon #1 Field Simplex (123 Hz TX tone)
        • 446.150 MHz Balloon #2 Field Simplex (123 Hz TX tone)
        • 446.200 MHz Balloon #3 Field Simplex (123 Hz TX tone)
        • 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)

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).

        Legacy 2M Simplex Frequency (not generally used due to desense/interference issues with the 2M APRS packets)
        • 146.550 MHz Simplex

2M Direction Finding Frequencies:

  • 144.340
  • 144.360
  • 144.905
  • 145.535
  • 145.645
  • 145.710
  • 145.765

 

Tactical Calls: 
TacticalCall SignNameNotes
AlphaW9CN, N0JDMike Pappas, Jeff DeatonRecovery Coordinator - With N0JD - Jeff
BravoKB0YRZChris KrengelTrack & Recovery
CharlieKC0RPS, W0GVJim Langsted, GerryFlight Coordinator;Track & Recovery†
DeltaN0JPSJohn SpainhowerFlight String, Track & Recovery†
EchoN0MMDoug Leber Escort from Launch Site†
FoxtrotK0NKKNancy KoosBalloon Fill;Track & Recovery†
GolfKE0UWC, KF0MBRGlenn Reker, JohnBalloon, Track & Recovery†
HotelKN0NLQAnne HerringtonBalloon Fill
† Starting from Launch Site
TR Breakfast: 
The tracker breakfast is at 7:00 am at the IHOP, Flying-J Truck Stop in Limon CO