EOSS-222/223/224 Metro State University and STEM flights - Recap

EOSS 222/223/224 were launched from the Limon launch site at approximately 0830 on May 21st.   EOSS-224 was found after 59 days hidden in a wheat field. See the galleries below for additional information.  

EOSS-222 landing site was at 39.65567 N, 103.03233 W

EOSS-223 landing site was at 39.56435 N, 103.136 W

EOSS-224 was found by a local farmer on July 19th while harvesting wheat at 39.58151 N, 103.06175 W

After four weeks of flight delays because of cloud cover, EOSS reconfigured the payloads into three balloons that can be launched through clouds. The balloons were launched from Limon Colorado. All three balloons were launched within seconds of each other. All balloons climbed at various ascent rates and burst at realtively high altitudes. EOSS-222 and EOSS-223 were tracked during descent and retrieved to the northeast. The tracking beacons on EOSS-224 suffered a series of failures and the final beacon failed soon after balloon burst, last reporting an altitude of 102,136 ft. A variety of descent predictions were used to identify serach locations. A week of air and ground searces were not successful in locating the payload string. Landowners were contacted and asked to watch for the payload. The payloads are labeled with "If found" telephone numbers. At this point, EOSS will have to wait for information.

Pre-launch webpage

Flight predictions and weather (WX) observations can be linked from this website. When we can, the launch will be at 0700. The intent is to launch the balloons 30 seconds apart. The daily flight path predictions are posted at this website. By clicking on the "GIF" link for the launch site, a map of the predicted flight path is available. This will change daily as the NWS models refine the wind pattern predictions. From Wednesday onward, the predictions are quite accurate. All sorts of flight and weather related links are posted here. Cloud cover at all levels must be less than 50% to fly. If not, we will scale the payload strings in order to fly within the weight restrictions to fly exempt. Sunday May 22nd has been identified as the alternate launch day.

See the payload plans posted below for each of the balloons.

MSU Denver Formal Logo


Event Date: 
Saturday, May 21, 2016 - 00:00
Flight Coordinator: 
Punkin Center X 10, Y 10, Test: N 39.300, W 103.200=X 36.7 Y 40.8


This balloon carries:

  • 3 Metro State Introduction to Space BalloonSats
  • 1 Metro State Tech Demo Payload

Balloon-specific Frequencies:

  • Caravan Leader APRS ID - KE7KCK-9
  • Caravan Ham Frequency - 446.275 MHz Simplex
  • FRS Channel - 2, CTCSS 2
  • Field Operations Frequency - 446.100 MHz Simple
  • For computer and smartphone tracking of the balloon, see:


Balloon Type: 
Totex 1200g Latex
8.5 ft circumference
147.420 MHzKØSCC-11APRS/Cutter/DF
144.340 MHzKC0UUO-11APRS/DigiSlotted at 00:00 and 00:30


This balloon carries: 

Balloon-specific Frequencies:

  • Caravan Leader APRS ID - TBD
  • Caravan Ham Frequency - 446.275 MHz Simplex
  • FRS Channel 3, CTCSS 3
  • Field Operations Frequency: 446.150 Simplex
  • For computer and smartphone tracking of this balloon, see:


Balloon Type: 
Totex 2000g Latex
5 ft circumference orange
145.600 MHzKEØBMV-11APRS/Cutter/DF
144.340 MHzAEØSS-12APRS/DigipeaterSlotted at 00:15 and 00:45


This flight will be an exempt flight with 4 Metro State University Introduction to Space BalloonSats and the Denver School of the Arts Amateur Radio Club test Beacon, KE0FXH-1.


Balloon Type: 
1600g Latex
5ft Red
147.555 MHzAE0SSCW/CutdownDF Beacon only
144.340 MHzAE0SS-11APRS Slotted at 00:20 and 00:50
144.390 MHzKE0FXH-1Student experimentDSotA Amateur Radio Club

Preflight Net:

  • 147.225 MHz CRA Repeater (107.2 Hz Tone) 8 pm MDT preceding night
  • 146.940 MHz (103.5 HZ Tone) RMRL Repeater if the CRA machine is down
  • 146.640 MHz (100 Hz Tone) DRL will serve as a backup frequency

Recovery Operations:

  • 449.450 MHz RMRL (103.5 Hz Tone)
  • 448.225 MHz (141.3 Hz Tone) Testing… PL verified 7/2/14
  • 446.100 MHz Field Simplex Balloon 1 EOSS-222
  • 446.150 MHz Field Simplex Balloon 2 EOSS-223
  • 446.200 MHz Field Simplex Balloon 3 EOSS-224
  • 146.550 MHz Backup field simplex
  • 446.275 Car to Car drive out frequency

Launch Site Simplex: 446.050 MHz


Tactical Calls: 
TacticalCall SignNameNotes
AlphaWAØGEH. KCØDMarty, MarkT&R Coordinator
BravoW9CN, KBØYRZMike, ChrisCo-Alpha,Trackers
CharlieKE7KCKTomFlight Coordinator, Tracker
DeltaKØSCC, KEØBMVStephen, ParkerLaunch Team, Trackers
EchoKDØSEMDaveLaunch Team, Tracker
FoxtrotNØNDM, WØCBHLarry, BenjieLaunch Team, Tracker
GolfKCØL JohnRemote Tracker, Texas
TR Breakfast: 
Launch is looking good for May 21. Marty and Mark will be Alpha for this flight, Mike, W9CN will co-Alpha for EOSS #224. We will meet trackers at Denny's in Limon at 6:00. Marty will run the net Friday night at 8:00 p.m. on the 147.225 CRA repeater. These flights will go! All flights will fly exempt. We are short-handed for trackers, so let's be on our toes. Be sure to download and read the payload plans. Be aware, the fields and roads may be muddy after this week's rains. See you during the net and in the field. Thank you all for your patience!