Editing Mariner 4 (section)

===Launch===
{{More citations needed|section|date=July 2019}}
After Mariner 3 was a total loss due to failure of the payload shroud to jettison, JPL engineers suggested that there had been a malfunction caused during separation of the metal fairing exterior from the fiberglass inner lining due to pressure differences between the inner and outer part of the shroud and that this could have caused the spring-loaded separation mechanism to become tangled and fail to detach properly.<ref name=mariner3_jpl/>

Testing at JPL confirmed this failure mode and an effort was made to develop a new, all-metal fairing. The downside of this was that the new fairing would be significantly heavier and reduce the Atlas-Agena's lift capacity. Convair and Lockheed-Martin had to make several performance enhancements to the booster to wring more power out of it. Despite fears that the work could not be completed before the 1964 Mars window closed, the new shroud was ready by November.<ref name=nasa4/>

After launch from [[Cape Canaveral Air Force Station Launch Complex 12]],<ref name=nasa5/> the protective shroud covering Mariner 4 was jettisoned and the [[RM-81 Agena|Agena-D]]/Mariner 4 combination separated from the [[SM-65D Atlas|Atlas-D booster]] at 14:27:23 UTC on November 28, 1964. The Agena's first burn took place from 14:28:14 to 14:30:38. The initial burn put the spacecraft into an Earth parking orbit and the second burn from 15:02:53 to 15:04:28 injected the craft into a Mars transfer orbit. Mariner 4 separated from the Agena at 15:07:09 and began cruise mode operations. The solar panels deployed and the scan platform was unlatched at 15:15:00. Sun acquisition occurred 16 minutes later.<ref name=NSSDC/>