The Aug. 12 liftoff of a United Launch Alliance (ULA) Vulcan rocket heralded a series of firsts.
It was Vulcan’s inaugural National Security Space Launch mission following its March 26 certification by the U.S. Space Force, the debut of the rocket’s four-solid rocket booster setup and its first mission of 2025.
But the payload it carried to geosynchronous orbit was also the nation’s first on-orbit experiment for position, navigation and timing (PNT) in nearly five decades. The Navigation Technology Satellite-3 (NTS-3) was built by L3Harris Technologies for the Air Force Research Laboratory (AFRL) to test new solutions for warfighters to operate in GPS-denied environments.
Vulcan launched the Space Force’s USSF-106 mission on Aug. 12 at 8:56 p.m. EDT from Cape Canaveral SFS, Florida, and spacecraft separation occurred approximately 7 hr. after liftoff, the service’s Space Systems Command confirmed Aug. 13.
AFRL, as the satellite’s operator, achieved first acquisition and is communicating with NTS-3 while performing checkout activities before beginning a year of planned experimental operations, AFRL Public Affairs Officer Jessie Perkins told Aviation Week Aug. 13.
The last time the U.S. sent a navigation experiment to space was in 1977, Joanna Hicks, senior research aerospace engineer at AFRL’s Space Vehicles Directorate, told reporters on Aug. 11.
The NTS-2 satellite was designed and built by the U.S. Naval Research Laboratory as the first in a four-satellite constellation to demonstrate instantaneous navigation positioning. It was launched June 23, 1977, aboard an Atlas E/F rocket–a converted ICBM that was used as a launch vehicle for small research satellites for more than two decades–from Vandenberg AFB, California. NTS-2 and its predecessor, NTS-1, were precursors to the GPS constellation, whose first operational satellite, Navstar 1, launched Feb. 22, 1978.
AFRL hopes that NTS-3 will support future GPS technology in the same way its predecessors supported the original fleet. The demonstration is timely, as U.S. competitors and adversaries deploy sophisticated jamming and spoofing capabilities meant to disrupt military and civilian activities that rely on GPS around the world.
The NTS-3 team plans to test more than 100 experiments, Hicks said. One new capability is the Chimera anti-spoofing signal to protect civilian GPS users, including airlines and the maritime industry, from nefarious activities.
The laboratory spent approximately $250 million on NTS-3, according to Hicks. The program features a space-based satellite, a ground-based control system and agile user receivers, all linked by reprogrammable software that allows for updates to be “pushed” to users in the field, similar to smartphone app updates. Previous GPS satellites required hardware replacements for upgrades.
It is also the first U.S. satellite navigation system to integrate phased array technology meant to send focused beams to ground forces and combat jamming environments, and to support simultaneous GPS broadcast and receipt, Andrew Builta, L3Harris vice president of strategy and business development for space and airborne systems, said Aug. 11. L3Harris plans to use the results from NTS-3 to validate its PNT design for the Space Force’s Resilient-GPS program, officials have said.