38mm minimum diameter rocket on I284 motor. RasAero simulation estimated 11,000 feet with top speed just over Mach 1.6 (recent flight on I161 went to 8,000 feet at Mach 1.0). However, the GPS transmitter stopped transmitting just after launch. Rocket has not yet been found. If you turn the volume WAY up after it leaves the launch pad, you can hear the apogee event at time=34seconds. Which is about right since it would take roughly 10 seconds for the sound to reach the ground if the event was two miles up. My apogee deploy events have a very loud "pop". The boost phase on this launch was arrow straight.