The actual flight path was approximately the same as previously predicted. The probe landing was expected in Talsi district. Shortly after the probe took off, the team went in the direction of Talsi. Halfway, in the direction of Talsi, when the balloon had reached a height of ~ 13 km, it was tested whether the signal transmitted by the probe could be received with its Uda-Yagi type antennas (directional antennas). Yes, the signal was received. The location of the probe on the map of Latvia was tracked using the information received on the server about GPS coordinates, which were obtained from several radio stations in Latvia. Several Latvian radio amateurs and an Estonian colleague were involved in the reception of the radio signal.

The signal transmitted by IRBE-3 was received from radio stations with the following call signals:

• YL1VA (Ventspils, Ervīns);
• YL3AKB (Lībagu parish, Mārcis);
• ES5TO (Igaunija, Tartu Observatory – Toravere, Viljo);
• YL2CP (Cēsis, Juris);
• YL2AO (Rīga, Juris);
• YL3AIY (Cēsis, Normunds);
• 310LA (Latvija);
• Minivat (Latvija).

The last GPS coordinates for the location of the balloon were received when it was 123 meters above the ground. The balloon landed 10 km north of Valdgale and was found after about 10 minutes, which is a good indicator. Examining the probe after it landed, it was concluded that it had not been damaged at the time of landing, and the video was still being recorded. This is very welcome, as this is the first time that the IRBE mission has succeeded in capturing the flight from take-off to finding the probe. The balloon burst prematurely, allowing the probe to reach a height of only 14 km, flight duration – 2 hours. After finding the probe, it was concluded that the latex balloon was of lower quality (ruptured the top of the balloon itself, which was originally thinner than the bottom of the balloon; it looked suspicious, but there was no way back) than before.

Some of the data obtained from the probe sensor subsystem:

• The minimum recorded ambient temperature -40 Celsius (14 km altitude);
• The minimum temperature inside the payload capsule is 10 degrees at an altitude of 8 km during the probe descent.
• The maximum temperature inside the payload capsule is 54 degrees at a height of 4 km when the probe is taking off.
• The minimum atmospheric pressure outside the capsule is 15.2 kPa (14 km altitude).
• The registered minimum humidity is 13.4% (14 km altitude).

Sensor measurement data (graphs) will be published on the social network Facebook IRBE page.

The IRBE-3 team says thanks:

• Ventspils University of Applied Sciences for the provided financial support;
• Ventspils Airport for the reception and the possibility to organize the start of the mission from the airport territory;
• SIA “Gaschema” for support for the purchase of helium gas;
• All radio amateurs who participated in the reception of the radio signal transmitted by the probe.
  

IRBE-3 team:

Gints Dreifogels,

Kaspars Prūsis,

Atvars Nikolajevs,

Mikus Freimanis,

Pēteris Pitāns