The LM crew performed the descent orbit insertion maneuver by firing their descent engine .
The LM crew tested their craft 's landing radar as they approached the 50,000 - foot ( 15,000 - meter ) altitude where powered descent would begin on Apollo 11 .
The LM crew performed the descent orbit insertion maneuver by firing their descent engine , and tested their craft 's landing radar as they approached the 50,000 - foot ( 15,000 - meter ) altitude where powered descent would begin on Apollo 11 .