24/09/2021
The Spartan missile was a further development of the Nike Zeus B missile. Spartan was originally called Nike-EX and was part of the Nike-X ABM system and provided the exo-atmospheric missile component of that system. Spartan was simply a longer range, heavier, higher performing Nike Zeus B missile. (The EX of the original Nike-EX name could have meant either EXtended range, or EXo-atmospheric indicating that it was now designed to intercept the RV outside the atmosphere). Externally, they are almost identical, the only real visible difference being that the 2nd stage is the same diameter as the first stage while the Nike Zeus B each stage is slightly smaller than the preceding stage. Spartan survived through the various planned deployments during the 1960s (ie Nike-X, Sentinel then Safeguard).
Flight testing of the missile did not commence until 1968 at Kwajalein and commenced without any major problems. Not surprising considering that the missile had been under test in some shape or form since 1959. Due to the high water table at Kwajalein, the launching of the Spartans presented a slight problem. Operationally, they had to be launched from silos, and so had to be tested from silos. However, the water table precluded the construction of silos below ground level without them flooding. So, the silo was built above ground in a rather large mound. This mound was locally known as "Mount Olympus".