Editing Apollo Lunar Module (section)

===Development flights===
[[File:67-H-1230 Lunar module LTA-2 R.jpg|thumb|The [[Apollo 6]] Lunar Module Test Article (LTA-2R) shortly before being mated with the SLA|250x250px]]

LM-1 was built to make the first uncrewed flight for propulsion systems testing, launched into low Earth orbit atop a [[Saturn IB]]. This was originally planned for April 1967, to be followed by the first crewed flight later that year. But the LM's development problems had been underestimated, and LM-1's flight was delayed until January 22, 1968, as [[Apollo 5]]. At that time, LM-2 was held in reserve in case the LM-1 flight failed, which did not happen.

LM-3 now became the first crewed LM, again to be flown in low Earth orbit to test all the systems and practice the separation, rendezvous, and docking planned for [[Apollo 8]] in December 1968. But again, last-minute problems delayed its flight until [[Apollo 9]] on March 3, 1969. A second, higher Earth orbit crewed practice flight had been planned to follow LM-3, but this was cancelled to keep the program timeline on track. [[Apollo 10]] launched on May 18, 1969, using LM-4 for a "dress rehearsal" for the lunar landing, practicing all phases of the mission except powered descent initiation through takeoff. The LM descended to {{convert|47400|ft|mi km|1}} above the lunar surface, then jettisoned the descent stage and used its ascent engine to return to the CSM.<ref name="chariots11-2">{{cite book|url=http://www.hq.nasa.gov/office/pao/History/SP-4205/contents.html|title=Chariots for Apollo: A History of Manned Lunar Spacecraft|author1=Courtney G. Brooks |author2=James M. Grimwood |author3=Loyd S. Swenson |year=1979|access-date=January 29, 2008|publisher=NASA|chapter=Chapter 12 Part 7|chapter-url = http://www.hq.nasa.gov/office/pao/History/SP-4205/ch12-7.html|isbn=0-486-46756-2| archive-url= https://web.archive.org/web/20080209003722/http://www.hq.nasa.gov/office/pao/History/SP-4205/contents.html| archive-date= February 9, 2008 | url-status= live}}</ref>