SpaceX Payload User’s Guides
SpaceX provides “User’s Guides” (Payload User’s Guides, or PUGs) for payloads going on Falcon 9, Falcon Heavy, or taking advantage of its Rideshare program. They’re all free to download from SpaceX. These are fairly comprehensive documents, including mission planning timelines and different environments: thermal, shock/vibe, pressure, etc., along with necessary mechanical and electrical interface specs. For our purposes, the section within “Environments” on “Electromagnetic” can be useful beyond only specific payload missions.
The purpose of this section is to let the user know what electromagnetic environments it might be exposed to, and also how it must limit its emissions in order to protect the RF and avionics systems of the launch vehicle. The limits are, on the whole, more lenient than the default limits found in MIL-STD-461, both for emissions and susceptibility, and can be very useful for tailoring EMC requirements and testing.
What I find particularly helpful is the set of limits in the image below. This is an envelope of the worst-case EM radiation environment between both the Eastern and Western launch ranges where SpaceX operates. (Presumably when Starship gets its own User’s Guide, the environment for the Texas base will be included as well.) This is incredibly helpful for planning what levels a piece of equipment should be robust enough to handle during all phases of operations leading up to launch: shipping, ground handling and checkouts, stacked and awaiting launch, as well as launch itself. This helps inform EMC radiated susceptibility test levels with a lot more granularity than the 20 V/m level set by MIL-STD-461, and is information that used to be hard to find.
