The baseline reference mission "3B" had the shuttle launching from Vandenburg, rendezvousing with and retrieving a satellite, and returning it to Earth all within a single orbit:


The timings quoted there are necessarily rather brief with a resolution in minutes and seconds:

Discard external tank         -  14:09
Park 100 feet from satellite  -  31:33
Complete stowing of satellite -  54:06
Deorbit maneuver              -  59:06 

With less than 23 minutes to grapple with the payload, bring it on board, and secure it the pace is hectic, especially as compared to actual retrieval missions such as the final Hubble servicing mission STS-125 which berthed Hubble within the shuttle some 60 hours after launch. However that has the circumspect pacing of missions after the loss of Columbia, starting with an extensive vetting of the thermal tiles. Are there examples from other missions of notably early major milestones, such as launching or retrieving satellites?


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No actually flown Shuttle mission executed such a quick timeline. The likelihood of crewmembers experiencing Space Adaptation Syndrome would have made it...interesting.

Crews were trained throughout the program to perform a superficially similar timeline called Abort Once Around (AOA) which also involved landing after a single rev. But major failures were required to get into an AOA and the timeline was substantially different than the reference mission in the question. For instance, the payload bay doors were not opened and the robot arm was not unstowed on an AOA. An AOA was never executed in reality, only in simulations.

Missions actually flown executed the almost two-hour duration Post Insertion Checklist which "converted their rocket into a space station" - i.e., configured the vehicle for orbital operations. This means that major payload operations involving several crew members did not normally begin before Mission Elapsed Time (MET) of ~ 3 hours.

Here is a summary timeline from the last mission's Flight Plan showing the Post Insertion timeline.

enter image description here

That said, Shuttle missions that deployed major payloads on upper stages often did so early in the flight.

The most recent such was STS-93 which deployed the Chandra X-ray observatory.

The mission's flight plan is not online, but here is the planned timeline from the press kit, which shows payload deploy at ~ 7 hours into the mission in the MET column. The event is listed as DEPLOY IUS - IUS being the carrier stage, the Inertial Upper Stage, to which the observatory was mounted.

Note that payload activities are actually started in the Post Insertion timeline! The AXAF (Advanced X-Ray Astrophysics Facility aka Chandra) was powered up.

enter image description here

This image shows the long observatory, ready for deploy, mounted on the relatively tiny IUS (marked with USA).

enter image description here

Image Source

The STS-70 mission which deployed a Tracking and Data Relay Satellite, again on an IUS upper stage, also had a first day deploy, this time at ~6 hours into the mission. Without checking them all, I would imagine all IUS-powered payloads got a first day deploy.

  • $\begingroup$ Was the early deployment of IUS-powered payloads driven by safety concerns? E.g. get the heavy stuff out of the payload bay so that an early return to Earth doesn't necessitate crudely dumping it. $\endgroup$ Sep 7, 2019 at 22:54
  • $\begingroup$ Pretty much - don't have a reference, but I think the philosophy was to get rid of it ASAP to give more time to work deployment problems if they happened and have less time for Orbiter problems to crop up. $\endgroup$ Sep 7, 2019 at 23:23
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    $\begingroup$ First day deploy missions were a joy to be an instructor for the integrated sims because the flight control team was hell-bent on deploying the payload and you could hammer them with failures that on other flights would prevent accomplishing major mission objectives. $\endgroup$ Sep 7, 2019 at 23:26

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