It was last assigned to the Long Range Proving Ground Division at Patrick Air Force Base, Florida.

Its mission was the supervision and evaluation of guided missile service tests as opposed to pure experimentation of its predecessor unit.

While the Holloman detachment continued to assist the Glenn L. Martin Company with developmental testing of the MX-771 Matador (i.e., it witnessed test firings and reported on the results), the Point Mugu detachment completed its Navy Convair Lark missile training and moved to the Joint Long Range Proving Ground in early January 1950 [1] On 1 July 1950, the 3d Guided Missiles Squadron was activated at the Long Range Proving Ground Air Force Base (later Patrick Air Force Base), on the Atlantic Coast of Florida.

The squadron launched three US Navy SAM-N-2 Lark surface-to-air missiles at Cape Canaveral in October and November 1950.

[1] While the 3201st Air Base Support Squadron was attached to the 550th for administrative purposes, its operations were essentially divorced from the 550th's missile activities when the 3200th moved to Eglin Auxiliary Field #3.