Amateur Satellite FalconSAT-3 Nears Reentry

Many amateur radio operators and satellite watchers have been predicting the date and time of reentry for FalconSAT-3 (FS-3). While all reentry predictions are something of a guessing game due to the large number of variables affecting the upper atmosphere, it is certain that the end for FS-3 will be coming very soon, possibly the week of 16-21 January 2023.

Radio Amateur Satellite Corporation (AMSAT) Board Member and FS-3 control operator, Mark Hammond, N8MH, said he will try to have the satellite operational for its final hours. The satellite has only been available for approximately 24 hours each weekend due to weak batteries.

FalconSAT-3 was built in 2005 and 2006 by cadets and faculty in the Space Systems Research Center at the US Air Force Academy (USAFA) in Colorado Springs, Colorado. It is the fourth in a series of small satellites designed, built, and operated there as part of a capstone course, which brings together about 30 cadets each year from several different academic departments.

Nearly 700 cadets at the USAFA obtained their amateur radio licenses as part of training to operate FalconSAT-3 and other USAFA satellites. They have taken that knowledge, understanding, and value of amateur radio into their Air Force service and industry. Since FalconSAT-3, the USAFA Astronautics Department has built and operated one additional satellite and has two more queued for launch. The space operations curriculum and the ground station are being rebuilt and configured for these new space assets.

Since its launch on an Atlas V rocket from Cape Canaveral in March 2007, the satellite has been through three mission phases. The first phase was operation of the science payloads. The second phase was used as a tool for training cadets in the space operations squadron, students in undergraduate space training in California, and graduate students at the Air Force Institute of Technology. The satellite's third phase was an on-orbit resource for amateur radio and amateur-satellite services operation managed by AMSAT.

Radio Amateur Satellite Corporation, AMSAT, logo; blue text with a red graphical globeFor amateur radio service the downlink is at 435.103 MHz transmitting 1 W into a quarter-wave whip antenna. The uplink is at 145.840 MHz and the receiving antenna is a quarter-wave whip antenna on the opposite side of the satellite. All UHF and S-band equipment on National Telecommunications and Information Administration licensed frequencies has been disabled. The VHF receiver is very sensitive. Modulation is 9600 bps GMSK for the uplink and downlink. The broadcast call sign is PFS3-11, and the BBS callsign is PFS3-12, Unproto APRS via PFS3-1.

The core avionics were designed and built by Mark Kanawati, N4TPY, and Dino Lorenzini, KC4YMG at SpaceQuest, and have performed remarkably well for nearly 16 years in orbit. Jim White, WD0E, was the lead engineer for FalconSAT-3 at the USAFA and managed the design, construction, testing, and early operations of the satellite.

The success of FalconSAT-3 is an excellent example of how amateur radio can be integrated into the curriculum of an education institution for the benefit of the students and the amateur radio service.