Did Apollo 10 face any problems?

Apollo 10 was the closest any Apollo spacecraft came to crashing and losing its crew.

Apollo 10 was a May 1969 dress-rehearsal for the Apollo 11 landing in July, and as such astronauts Tom Stafford and Gene Cernan took the Lunar Module Snoopy down to within 8.4 miles of the Lunar surface before levelling off and ascending to rendezvous with John Young in the Command Module.

A misunderstanding between Stafford and Cernan resulted in Stafford accidentally setting the Lunar Module radar to lock on the moon. Cernan had already re-set the radar to lock on to John Young in the Command Module but had failed to inform Stafford, who then leant back and flicked the same switch into the mode it had been in moments before.

When the radar computer was activated it therefore flipped the Lunar Module onto its back and began powering it down toward the moon rather than upward toward the orbiting Command Module. Stafford and Cernan spent 10 seconds tumbling head over heels before realising their mistake and recalibrating the computer. Had the spinning lasted for a second longer it was later calculated Snoopy would certainly have crashed and killed both Cernan and Stafford.