Before the attempt could be made for the manned lunar landing, the spacecraft and systems had to be tested to be sure they would work as designed. Apollo 9 was that critical mission. It is often overlooked but the mission tested the complete Apollo spacecraft in space for the first time. It was the first manned flight for the lunar module. The mission took place from March 3 thru March 13, 1969 with an outstanding crew - David Scott, James McDivitt and Russell "Rusty" Schweickart. The critical mission objective was the testing of the lunar module "Spider". On March 7 (mission day 5) Spider separated from the command module "Gumdrop". After spending about 45 minutes near Gumdrop, the descent engine was fired taking Spider into a higher orbit which eventually separated the two spacecraft out to about 115 miles. The descent engine was fired several more times during maneuvers. The LM ascent stage was separated from the descent stage by firing explosive bolts. The ascent engine was fired to bring Spider back to rendezvous with Gumdrop.