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Since we did not recover the rocket or payload, we cannot verify this was the failure we experienced with 100% certainty, but no other proposed theories explain why both BRB's lost lock at the same time and continued to send good APRS packets.

Potential Root Causes

• Lack of knowledge
  • Unknown failure mode prior to flight
  • Hard to mitigate short of a test flight
• Launched too late
  • More recovery time would have given us a better chance to find the rocket without GPS
• Lacked directional antenna
  • A directional antenna could have been used to get a heading using signal strength from the APRS packets that were being transmitted
  • Our recovery teams had dipole antennas making it impossible to get a heading from a single point

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