Editing Apollo 6 (section)

===Orbit===
Due to the less-than-nominal launch, the CSM and S-IVB were inserted into a {{convert|93.49|nmi|km|adj=on|order=flip|sp=us}} by {{convert|194.44|nmi|km|adj=on|order=flip|sp=us}} parking orbit, instead of the planned {{convert|100|nmi|km|adj=on|order=flip|sp=us}} circular parking orbit.<ref name="lver" /> This deviation from the flight plan did not preclude continuing the mission.{{sfn|Orloff & Harland 2006|p=154}} During the first orbit, the S-IVB maneuvered, changing its attitude towards the horizon to qualify techniques that future astronauts could use in landmark tracking. Then, after the standard two orbits to assess the vehicle's readiness for [[trans-lunar injection]] (TLI), the S-IVB was ordered to restart, but failed to do so.{{sfn|Orloff & Harland 2006|pp=354–356}}

Deciding on a pre-planned alternate mission,{{sfn|Orloff & Harland 2006|p=356}} the [[Flight controller#flight director|flight director]], [[Clifford E. Charlesworth]] and his team in [[Christopher C. Kraft Jr. Mission Control Center|Mission Control]] chose to use the SM's [[Service Propulsion System]] (SPS) engine to raise the spacecraft into an orbit with a high [[apogee]] (point of furthest distance from Earth), with a low [[perigee]] that would result in re-entry,<ref name = "legacy" /> as had been done in Apollo 4. This plan would complete some of the mission objectives. The SPS engine burned for 442 seconds to get to the planned {{convert|11,989|nmi|km|adj=on|sp=us|order=flip}} apogee. There was now, however, not enough propellant to speed up the [[Atmospheric entry|atmospheric reentry]] with a second SPS engine burn, and the spacecraft only entered the atmosphere at a speed of {{convert|33,000|ft/s|m/s|order=flip|sp=us}} instead of the planned {{convert|37,000|ft/s|m/s|order=flip|sp=us}} that would simulate a lunar return.{{sfn|Brooks 1979|p=249}} While at high altitudes, the CM was able to return data on the extent to which future astronauts would be protected from the [[Van Allen Belts]] by the skin of the spacecraft.{{sfn|Orloff & Harland 2006|p=356}}

Ten hours after launch, the CM landed {{convert|43|nmi|km|order=flip|sp=us}} from the planned touchdown point in the North [[Pacific Ocean]] north of [[Hawaii]], and was lifted on board {{USS|Okinawa|LPH-3|6}}.{{sfn|Brooks 1979|p=249}} The SM was jettisoned just before reaching the atmosphere and burned up.{{sfn|Orloff & Harland 2006|p=157}} The S-IVB's orbit gradually decayed and it reentered the atmosphere on April 26, 1968.{{sfn|Orloff & Harland 2006|p=156}}