On the morning of April 20th, a caravan of cars packed to the brim with more than 100 college rocket enthusiasts will make its way to Spaceport America and attempt to make history. The USC Rocket Propulsion Lab’s fourth space shot, Traveler IV, would be the first student-engineered-and-built rocket to pass the Karman Line, the widely-accepted boundary between the atmosphere and space.

Four days out from the launch, spirits were high among team members during a dry run through of launch on Tuesday night, which ran into the early hours of the morning. The team planned and executed a full run through because of the failure of their last attempt, Traveler III.

“On [Traveler III], everything seemed to work,” Lauren Potterat, RPL’s avionics software lead, said. “Everything went as planned, [there was a] sonic boom at five minutes. It was more of an interpersonal protocol issue than a technical issue.”

Traveler III was launched in September of 2018 and appeared to function as planned, but a miscommunication resulted in the rocket launching without the onboard avionics package turned on. This led to a ballistic landing– basically, the rocket smashing into the ground– and no recoverable data for the engineers at RPL.

Traveler IV’s fins are attached to the airframe using a custom wooden fin jig / Joseph DeRose

 

The Traveler IV rocket is extremely similar to Traveler III, the team’s previous attempt to get into space. The most fundamental change is in the avionics unit, which was designed and built from the ground up for Traveler IV. The rocket’s motor is powered by a proprietary propellant recipe and is basically unchanged, and the motor case and airframe were built using the same wound carbon fiber construction.

RPL members layup additional carbon fiber layers to strengthen the connection between the airframe and the fins / Joseph DeRose

The motor was successfully integrated into the airframe successfully on April 12 (integration is basically covering with extremely strong glue and forcing it into another, the airframe), and left USC’s campus on Wednesday for Spaceport America.

The Rocket Propulsion Lab, often abbreviated as RPL, was founded in 2005 with the overall goal of reaching space. Since then, the Lab has flown 12 different airframes and motors, according to their website, and already claimed their place in the record books, flying Fathom II higher than any other student-designed-and-built rocket. Their attempted space shots, the Traveler missions, have been less successful. “Traveler”, billed by RPL’s website as the world’s first collegiate space shot attempt, failed. Traveler II exploded at around 4,000 feet. Despite delays and failures during the build process, Traveler III is the closest the team has come to achieving their goal.

Traveler III during integration before the September launch / Joseph DeRose

If you want to follow along with the team this weekend, the lab is expecting to live stream the launch from their facebook page. A documentary following RPL beginning with the Traveler III project is currently in production and will eventually be released for free online. Traveler IV is scheduled for launch in New Mexico on Saturday morning at around 8 a.m., weather permitting.