How many times were there thirteen people inside the ISS? Is it hard on the station?

I just saw this photo in @SF.'s answer It is ISS023-E-023513 STS-131 and Expedition 23. The full caption is below.

Are there really 13 people on the ISS at one time?

Is STS-131 the only shuttle mission that resulted in 13 people being inside the ISS?

I'm wondering about the load on the station from the extra number of bodies; water vapor, CO2, particulates, movement/vibrations... were any of these at all an issue? How long did this last - just enough for a photo op or did it last a while?

I wanna ask if the shuttle crew were allowed to use the facilities on the ISS or if they had to go back to the shuttle, but I'm too shy.

ISS023-E-023513 (14 April 2010) --- STS-131 and Expedition 23 crew members gather for a group portrait in the Kibo laboratory of the International Space Station while space shuttle Discovery remains docked with the station. STS-131 crew members pictured (light blue shirts) are NASA astronauts Alan Poindexter, commander; James P. Dutton Jr., pilot; Clayton Anderson, Rick Mastracchio, Dorothy Metcalf-Lindenburger, Stephanie Wilson and Japan Aerospace Exploration Agency astronaut Naoko Yamazaki, all mission specialists. Expedition 23 crew members pictured are Russian cosmonauts Oleg Kotov, commander; Mikhail Kornienko and Alexander Skvortsov; Japan Aerospace Exploration Agency astronaut Soichi Noguchi, and NASA astronauts T.J. Creamer and Tracy Caldwell Dyson, all flight engineers.

• It looks like this answer needs to be updated? – uhoh Jun 2 '17 at 16:14
• Each crew used the toilet in their own vehicle (barring failures) – Organic Marble Jun 2 '17 at 16:34
• STS-131 was docked to the ISS for 10 days. During that time there were no Soyuz arrivals or departures, so the ISS had 13 crew for those 10 days. (en.wikipedia.org/wiki/STS-131) – Hobbes Jun 2 '17 at 19:28
• @Hobbes perhaps I should have used "in" instead of "on"? I'll make the change. I'm wondering about "...the load on the station from the extra number of bodies; water vapor, CO2, particulates, movement/vibrations..." which would depend upon the location of the STS crew - visiting the ISS or back in the shuttle. – uhoh Jun 3 '17 at 0:29
• The Flight Plan should give a definitive answer, but from the Wikipedia article it looks like part of the Shuttle crew spent a lot of time on the station, helping unload the MPLM and install new part for the station. There were a number of spacewalks, with 2 astronauts outside the ISS for 8 hours at a time. Early and late in the mission, some of the Shuttle crew had tasks on the Shuttle. – Hobbes Jun 3 '17 at 7:48

The only 2 missions I am aware of that had 13 people in the ISS at one time are STS-131 (as listed in the question) and STS-127. Here is the analogous crew photo from that mission.

Which crewperson was in which vehicle can be teased out of the Flight Plan by following their assigned tasks through the Summary Flight Plan section. This does require that one knows where a task is performed, but for the full complement it would pretty much have to be in the ISS (or the interface, for the welcome ceremony). Once they dock on Flight Day 3, the Plan turns into a two-page format with shuttle crew on one page, ISS crew on the other.

I have attached a screenshot from the STS-131 Plan showing when their crew photo was planned to happen (Flight Day 09, 01:00 hours Mission Elapsed Time).

However, just like battle plans don't survive contact with the enemy, Flight Plans don't survive contact with the mission, and updates are sent up daily.

I am sorry the resolution is so low, I wanted to show both pages. You can download the Flight Plan .pdf and see it in all its high res glory if you like.

A quick flip through the Plan showed the welcome ceremony and safety briefing also involving all crewpersons. I could easily have missed something, and there were almost certainly informal occasions (meals, etc) not shown.

As being hard on the station, I am sure that all 13 could not stay there for a long time, but all of this was obsessively planned and analyzed. Please see Hobbes's answer for details.

• This is great! They ate separately for practical reasons, then got together after lunch for a photo and possibly for the crew confafter. Do you think that 13 souls on board only happened during STS-131/Expedition-23? I probably should have asked for how many missions rather than how many times. – uhoh Jun 2 '17 at 17:24
• I think the only other time was STS-127 that is mentioned in the answer that you linked to in a comment beneath the question. At the time IMHO that was the record for most people in orbit in a single spacecraft. – Organic Marble Jun 2 '17 at 17:29
• Were there 13 people inside the ISS proper at the same time for STS-127? – uhoh Jun 2 '17 at 17:43
• OK! It looks like "twice" is the answer I'm really after; I've edited the question and added the sentence "Is STS-131 the only shuttle mission that resulted in 13 people being inside the ISS?" I've also changed "on the ISS" to "inside the ISS". I think I underestimated the complexity of dealing with crew movements! – uhoh Jun 3 '17 at 0:36
• @uhoh I finally got around to updating this. Please see if it answers the question now in the actual answer, not just in the comments. – Organic Marble Jul 4 '17 at 1:09

To answer the part 'is is hard on the station':

The air conditioning system can cope with at least 12 people on board continuously. There are 3 systems for removal of carbon dioxide: 2 Carbon Dioxide Removal Assembly (CDRA) and Vozdukh, each is designed to remove the CO2 generated by 6 people.

I get the impression capacity is slightly more than that, to account for experiments that use oxygen (e.g. live animals).

Vozdukh is primary and can scrub the air for a six person crew. It uses less power than CDRA. CDRA serves as a backup and for additional support when the crew complement is higher (such as when there was a visiting shuttle crew). As a further backup for contingency cases, the Russian Segment also has LiOH canisters that can adsorb contaminants.

Oxygen is supplied from pressure vessels, so that 's a matter of logistics.

The waste water recovery system is designed for a load of 6 people.

There are 2 systems that remove the excess humidity (from breathing, perspiration and evaporation, e.g. from wet towels) from the air.

The ISS has two water recovery systems. Zvezda contains a water recovery system that processes water vapor from the atmosphere that could be used for drinking in an emergency but is normally fed to the Elektron system to produce oxygen. The American segment has a Water Recovery System installed during STS-126 that can process water vapour collected from the atmosphere and urine into water that is intended for drinking.

total capacity of these 2 systems is 12 people.

• The strange thing is that while Vozdukh is translated as "Air", and it's obvious what it does, why Zvezda ("Star") has anything to do with water is unclear. – polkovnikov.ph Jun 3 '17 at 23:15
• Zvezda is the name of the ISS module that contains the life support systems. (en.wikipedia.org/wiki/Zvezda_(ISS_module)). Zvezda has 4 docking ports and is one of the central parts of the station. – Hobbes Jun 4 '17 at 10:26
• Thanks for the helpful addition. These days, does much of the oxygen consumed come from electrolysis, or is that also for backup? – uhoh Jun 4 '17 at 17:18
• When a shuttle is docked, its life-support systems can help out, too, can't they? Or maybe there's not enough air-circulation between shuttle and ISS for that to work in practice? – Peter Cordes Jun 5 '17 at 2:00
• From what I've seen (in ISS documentaries) air circulation is a problem, they've got air hoses running everywhere to get enough circulation. – Hobbes Jun 5 '17 at 7:46