Although U3B-2 slowed down a lot over the Bay of Biscay, but it did still cross the Spanish coast only 48 hours after launch. A fast transatlantic crossing! U3B continued down the Portuguese Atlantic coast. It continued transmitting for 3 hours after sunset again. The lowest temperature reported was -39C.
Very fast progress across the North Atlantic Ocean today! It sustained a peak ground speed of 134 knots for several hours (154mph, 248kph). After sunset U3B-2 operated down to temperatures as low as -37C. This temperature measurement uses an LM75 with I2C interface, it is an accurate way of measuring temperature. It is great that the electronics, and particularly the battery, continue to work at such a low temperature.
U3B-2 was launched at 1900Z from Toronto and ascended quickly. U3B-2 passed up through the 10,000m "barrier" at 2200Z without incident, so the SIM28 GPS now works Ok above 10km altitude when the serial data commands are sent to it to put it into high altitude balloon mode.
It was very interesting to note that U3B-2 continued to transmit until 3 hours after sunset! The U3B flight computer is designed for low power consumption. It is nice to see that this aspect of the design is working nicely. Interesting also that the LiPo batteries continued to operate down to well below -30C. The coldest temperature was -36C.
Launch was at about 1900Z from Toronto on 04-Jul-2017.
The U3B-2 has a 100mAh LiPo battery, and uses the SIM28 GPS module which caused problems on lots of Dave VE3KCL's earlier flights because it cuts out over 10km altitude. For this flight the firmware has been modified to allow sending a command to the GPS module to cause it to be put into a high altitude mode where it should work above 10km altitude.