The Nike "Ajax" project was followed up by the Nike "Hercules" just a little while later. The Ajax had problems with its fuel system as well as the limited capabilities when it was in the air. The Hercules looked to improve upon the distance, speed, and guidance capabilities. The historical marker in Pennsylvania includes a replica Hercules missile.
After the limited success of the Nike "Ajax" the US military looked to improve upon their weapons by building the Nike "Hercules". The Hercules was rolled out to improve upon the first model in speed, distance, and altitude. The Ajax was limited in these uses whereas the US believed the Soviets were trying different models of smaller aircraft that was much improved upon their previous models. Hercules was also built to be safer and more reliable in transport.
The Hercules was also equipped with a small nuclear warhead itself in order to stop a nuclear attack. "W-31" was carried in an arm of the warhead in different sizes and could destroy aircraft clusters. In addition to the warhead was a significant upgrade in the guidance system making it more precise at far away targets.
The Hercules was reported as well as all the Ajax missiles to be disbanded in 1974 although there are many reports that the military still used the rockets through part of the 1980s. The missiles were considered at the time a surplus whereas the government deemed them costly. Nike missiles are still deployed by other countries in Europe and Asia.
The monument erected in Pennsylvania is little more than a statue to a once powerful program for the US government during the Cold War. Very few sites were the missiles could be launched are still intact.
1. http://www.hmdb.org/marker.asp?marker=12584, viewed November 15, 2015
2. http://alpha.fdu.edu/~bender/N-view.html, viewed November 15, 2015
3. http://www.historylink.org/index.cfm?DisplayPage=output.cfm&file_id=9711, Denfield Duane, March 19, 2011, Mark A. Berhow and Mark L. Morgan, Rings of Supersonic Steel: Air Defenses of the United States Army 1950-1974 (Bodega Bay, California: Fort MacArthur Press, 2002); John C. Lonnquest and David F. Winkler, To Defend and Deter: The Legacy Of The United States Cold War Missile Program (Washington, D.C.: Department of Defense Legacy Program, November 1996); “History of Nike Missile Sites Near Fairchild Air Force Base, Washington,” Air Force Base Realignment and Closure website accessed December 10, 2010 (http:airforcebrac2005.org.); “Guided Missiles Can Be Launched in Area,” The Seattle Daily Times, November 16, 1954, p. 13; “Three New Nike Sites Planned In Seattle Area,” The Seattle Daily Times, March 30, 1955, p. 24; “Washington Missilemen Are Deadly,” The Seattle Daily Times, November 2, 1963, p. 11; “Born-again homes are affordable”, The Seattle Daily Times, November 1, 1981.