EVA and VKD Program

[vp.]

For 2026

The Russians regularly communicate about their program.
So, it is known that Kud-Sverchkov and Mikaiev will perform two VKDs during Expedition 75.

The first VKD (No. 66) is scheduled for April 2026 to install the Sun-Terhertz experiment and replace the second cassette on Ekran-M.
The second VKD (No. 67) is planned for June 2026 to replace the coolant in the Zarya thermal control panel.


On the American side, there is no official information.

However, we know that many tasks need to be completed:
- Onishi trained specifically to replace a camera on Kibo.
- Fincke and Kim trained to perform 3 or 4 EVAs to upgrade the AMS-2.
- One EVA must be performed to install the last iRosa mount.
- Two EVAs are needed to install the last two iRosa will be transported by Dragon CRS-34.
- The new IDA reflector, which is to replace the one removed during EVA 91, arrived with Cygnus NG-23.
- A Canadarm elbow needs to be replaced (preparation made during EVA 92).
- Two cooling pumps may need to be replaced (2x3 EVAs).

[Yellowstone10]

Thoughts on each of those listed tasks...

 - The Kibo RMS camera R&R is (I think) a generic task they use in EVA training, not necessarily something they would specifically rehearse only because they're planning to do it on orbit.
 - The AMS-02 Tracker Layer 0 install obviously depends on launch timing. I found a CERN article from June 2025 mentioning a "spring 2026" launch - that's the most recent mention I can find, not sure if it's still accurate though.
 - They've actually got about one and a half iROSA mod kits to install, since they only got partway through the 2A mod kit installation on EVA-93. Might require 2 separate EVAs?
 - The two iROSA installation EVAs are also definitely tied to the corresponding Dragon CRS flight. If we assume two flights next year, probably one has the iROSAs (and those EVAs) while the other has AMS-02 Layer-0 (and those EVAs)?
 - An IDA reflector was replaced (not just removed) on EVA-91. Not sure if the one that flew on NG-23 is to have an on-orbit spare, or if a second reflector needs replacing.
 - The planned SSRMS elbow joint task on EVA-92 (which, IIRC, was deferred due to the RFG retrieval taking longer than expected) wasn't prompted by a need to replace the joint, it was just to make sure it was in a good/convenient config if such a replacement was needed later.
 - The Pump Module replacements also appear to be "if needed".

[russianhalo117]

NSF forum member cohberg might be able to check DOUG and other ISS resources and see about any planning updates et al.

[cohberg]

^{Re: DOUG + Russian EVAs}

might be able to check DOUG and other ISS resources and see about any planning updates et al.

Unfortunately, DOUG packages for Russian EVAs are no longer publicly released by NASA post 2022. I asked around about the change and the NASA Engineering VR Technical Discipline Lead graciously got back to me via email and explained (and I quote) that the "policy changed a few years ago when we go some pushback from our EVA stakeholders".

I'll leave the interpretation of "stakeholders" up to the reader. Only Russian EVAs flight file posting were affected, US flight files are still posted, and 2022 was a significant year for geopolitical events. I even tried to FOIA the DOUG files, and the final response was that the files did not exist (despite EVA movies based on DOUG being shown in press briefings well after 2022).

^{Re: DOUG + US EVAs}

Some backing items for Yellowstone10's commentary from a fresh tranche of DOUG releases today (12/26/2025)

They've actually got about one and a half iROSA mod kits to install, since they only got partway through the 2A mod kit installation on EVA-93. Might require 2 separate EVAs?

Newly posted flight package us-eva-irosa-prep-2a-pt-2-v5 (steps attached) is just completing 2A. 3B is not included in that package.

Salo actually has 3B up next, but I have not seen any DOUG packages for this.

Not sure if the one that flew on NG-23 is to have an on-orbit spare, or if a second reflector needs replacing.

It appears that they are going to replace the fwd IDA's reflector as well (along with 3 jumper relocations [us-eva-triple-jump-v9]). Based on the posting order and get-aheads, us-eva-triple-jump-v9 may be next on the docket.

[vp.]

NASA ISS blog post for December 16:

https://www.nasa.gov/blogs/spacestation/2025/12/16/stem-cells-robotics-and-spacesuits-top-station-crew-day/

NASA Flight Engineers Zena Cardman and Chris Williams partnered together during the first half of their shift on Tuesday and resized a pair of spacesuits inside the Quest airlock. The duo adjusted the suits’ arms, legs, and waist ahead of a pair of maintenance spacewalks planned for early 2026.

[russianhalo117]

NASA ISS blog post for December 16:

https://www.nasa.gov/blogs/spacestation/2025/12/16/stem-cells-robotics-and-spacesuits-top-station-crew-day/

NASA Flight Engineers Zena Cardman and Chris Williams partnered together during the first half of their shift on Tuesday and resized a pair of spacesuits inside the Quest airlock. The duo adjusted the suits’ arms, legs, and waist ahead of a pair of maintenance spacewalks planned for early 2026.

The order in DOUG:
94: us-eva-triple-jump
95: us-eva-irosa-prep-2a-pt-2

[John_Marshall]

NASA ISS blog post for December 16:

https://www.nasa.gov/blogs/spacestation/2025/12/16/stem-cells-robotics-and-spacesuits-top-station-crew-day/

NASA Flight Engineers Zena Cardman and Chris Williams partnered together during the first half of their shift on Tuesday and resized a pair of spacesuits inside the Quest airlock. The duo adjusted the suits’ arms, legs, and waist ahead of a pair of maintenance spacewalks planned for early 2026.

Does this mean that they are likely to be the two who go outside, or is it possible that they are prepping them for others?

[cohberg]

Confirmation of EVA order and dates:

94: us-eva-irosa-prep-2a-pt-2
95: us-eva-triple-jump

12/29/2025
On Thursday, Jan. 8, NASA astronauts Mike Fincke and Zena Cardman will exit the station’s Quest airlock to prepare the 2A power channel for future installation of International Space Station Roll-Out Solar Arrays. Once installed, the array will provide additional power for the orbital laboratory, including critical support of its safe and controlled deorbit. This spacewalk will be Cardman’s first and Fincke’s 10th, tying him for the most spacewalks by a NASA astronaut.

On Thursday, Jan. 15, two NASA astronauts will replace a high-definition camera on camera port 3, install a new navigational aid for visiting spacecraft, called a planar reflector, on the Harmony module’s forward port, and relocate an early ammonia servicer jumper — a flexible hose assembly that connects parts of a fluid system — along with other jumpers on the station’s S6 and S4 truss.

[vp.]

Informations for futur AMS upgrade EVA.
https://indico.cern.ch/event/1542546/attachments/3064290/5420478/20250509_AMS_CorradoGargiulo.pdf

[Yellowstone10]

Informations for futur AMS upgrade EVA.
https://indico.cern.ch/event/1542546/attachments/3064290/5420478/20250509_AMS_CorradoGargiulo.pdf

For what it's worth, Eric Berger has mentioned in the comments of an Ars Technica article that he's heard from sources that the AMS Layer-0 upgrade has been the victim of budget cuts.

[vp.]

Informations for futur AMS upgrade EVA.
https://indico.cern.ch/event/1542546/attachments/3064290/5420478/20250509_AMS_CorradoGargiulo.pdf

For what it's worth, Eric Berger has mentioned in the comments of an Ars Technica article that he's heard from sources that the Layer-0 upgrade has been the victim of budget cuts.

What are the sources?

[russianhalo117]

Informations for futur AMS upgrade EVA.
https://indico.cern.ch/event/1542546/attachments/3064290/5420478/20250509_AMS_CorradoGargiulo.pdf

For what it's worth, Eric Berger has mentioned in the comments of an Ars Technica article that he's heard from sources that the Layer-0 upgrade has been the victim of budget cuts.

What are the sources?

2026 White House budget.
Not sure if it survived in the Minibus bill. Would have been likely under the undefined Physics of the Cosmos Programme category which was nixed entirely. Work was still underway in Q4. The hardware is built and the US is primarily funding the AMS-02.2 project upgrades launch and installation via NG-24 (Layer-1 Radiators) and SpX-34 (Layer-0 Tracker and PDS Radiator). All primary operations are via the control center at CERN. JSC and other global control centers have contingeny payload control rooms for ISS payloads which can be handed over to as needed once a crew arrives. Only the MSFC POC and CERN CC have permanent staff.

[vp.]

So, the next 5 EVAs should therefore be:

EVA94: completion of Modkit-7 prep iRosa 2A installation
EVA95: camera port 3 + Harmony front port reflector + fluid system on S6 and S4 truss
EVA96: Modkit-8 iRosa prep 3B
EVA97: Install iRosa 2A on the P4 truss segment
EVA98: Install iRosa 3B on the S6 truss segment

All these EVAs will be performed by Increment 74

And after ?