USC just released their flight report claiming to have gone past the Karman line. There is a lot of intersting stuff in there but I want to focus on one item: GPS Two GPS receivers were on board and both lost lock at launch as expected. What wasn't expected is the long delay before lock was acquired again. There was a long time period after acceleration dropped below 4G's and altitude reached the 50km lock out of the uBlox receiver in the BRB but it didn't get a lock. There was also a long delay after dropping below 50km. There are more dynamics that just the linear acceleration. The gold standard for GPS antennas in rockets/missiles is a wrap around design. The big advantage here is a consistent phase center that is located on the longitudinal axis. See figure 3.2 of RCC 322. The BRB has a simple patch antenna and its location is not mentioned. I suspect that no care was taken to place it on the vehicle centerline. Which means that the >6 rps rotation spun it around creating additional dynamics. Short of throwing a bucket of money to Haigh-Farr, or some other antenna vendor, the least you should do is put the antenna on the centerline if you expect significant rotation rates. Another problem that will make things worse is the aerodynamic heating. This raises the RF noise floor and will push a marginal link over the edge.