The U.S. Air Force Academy’s Department of Astronautics has proven once again that it is indeed providing cadets the opportunity to “learn space by doing space.”
FalconSAT, the academy’s capstone undergraduate space systems engineering course, managed by the Department of Astronautics, launched its latest small satellite late last year.
On Nov. 19, 2010, FalconSAT capstone cadets got to see the completion of this multi-year process when FalconSAT-5 was launched from Kodiak, Alaska, aboard a Minotaur IV launch vehicle.
Sponsored by the Air Force Research Lab (AFRL), FalconSAT-5’s mission is to perform space weather measurements with on-board sensors and collaboration with remote ground sites. The onboard payloads include the Integrated Miniaturized Electrostatic Analyzer (iMESA) and the Wafer Integrated Spectrometers (WISPERS), which measure low and high-energy ion densities, an off-the-shelf plasma source named the Space Plasma Characterization Source (SPCS), and the Radio Frequency (RF) Signal Strength (RUSS) payload.
This suite of experiments provides the ability to measure the local ionosphere, stimulate the local environment and measure the subsequent changes, and evaluate ionospheric effects on RF signals for communication impacts.
“For example, the sensors onboard can measure perturbations [changes affecting the orbital environment] in the upper ionosphere, and we care about those because they actually affect communications links,” explained Steve Hart, chief engineer, Department of Astronautics Space Systems Research Center. “If you held a GPS receiver in your hand and a perturbation of the ionosphere occurred, it’ll actually slow down the electromagnetic wave, causing you to appear as if you’re moving, even though you’re not, according to your GPS receiver. Not a big deal if you’re sitting in your chair; big deal if you launch a GPS-guided munition.
“It’s a space weather experiment where we are looking at the ions that we know are out there so we can calibrate our system and then we can go look at this and see if we can then begin to measure and predict when these things can occur so they don’t cause us or our troops problems in the field.”
The FalconSAT-5 program will collaborate with ground sites to include the U.S. Army Kwajalein Atoll/Reagan Test Site, which routinely hosts programs that study the space environment. Dual-frequency tracking of FalconSAT-5 is a unique opportunity to characterize the poorly understood ionospheric atmosphere. The AFRL Spacecraft Propulsion Branch will also utilize on-orbit data from the iMESA, WISPERS, and SPCS payloads to correlate ongoing spacecraft/thruster interaction models, such as Coliseum.
“We’d like to take the data at different times of the year, different times relative to the sun, all the things that are variable,” Professor William Saylor, Bernard Schriever chair, Department of Astronautics, further explained. “In six months, we could meet minimum requirements, so in one year of normal operation we could greatly exceed expectations. The plan is that the satellite should operate for a minimum of three to five years.”
While the FalconSAT-5 mission has just recently begun, Col. Martin France, permanent professor and head of the Department of Astronautics, and two cadets who were in Kodiak for the launch, saw years of planning and hard work on the satellite come to fruition when it successfully launched as a secondary payload on the Department of Defense (DoD) Space Test Program’s S-26 mission.
“I’ve seen launches that go well and some that go very poorly,” France shared. “I don’t think I was really nervous at all on this one because it’s a proven system. The countdown and everything leading up to launch had gone flawlessly and the weather was perfect. There was no reason to suspect that anything would go wrong and nothing went wrong. It couldn’t have been smoother.
“I think as soon as it got off the pad and we saw it successfully heading to orbit, my thoughts almost immediately turned to: When we try to contact the satellite the next morning, will it be there? Will it listen, will it react, will it be healthy on orbit? That worried me much more, and I set my alarm and got up at 3:30 in the morning to hear the report from the pass in Colorado at 5:30.”
Everyone involved with the satellite was a bit concerned when there was no communication from it the morning after it launched and made its first two passes over the ground station at USAFA.
“The first two passes were zeroes and we didn’t hear anything from the satellite, but we have a great team and a great group of mentors with the cadets, and they did the right thing and tried to solve the problem and figure out where the problem resided,” France explained. “The cadets got to participate in that, too, which is part of the learning experience. And later that day, we got contact with the satellite and fixed a few problems.”
FalconSAT-5 continues to proceed with its initialization, although slower than expected due to a few problems with the spacecraft and the ground station. The staff and cadets in the Astronautics Department are troubleshooting each problem as they arise, and consulting with experts in the industry to resolve the issues. Once the spacecraft transitions to nominal operations, it will collect 10-100 times more data than the minimum requirements outlined by their customers over its three to five year expected lifetime.
Even with these problems and challenges, cadets in the FalconSAT program are gaining invaluable experience that cannot be replicated in a standard classroom environment.
“These aren’t just practices, they’re not simulations, they’re real Department of Defense missions,” France concluded. “The data we produce, the information we get from our satellites goes to other organizations throughout the DoD and they use that and depend on the information we gather for them for further research, for advancing the state of the art in different satellite components. Giving the cadets that opportunity can’t help but make them better officers and leaders down the road.”