For years the answer to "how does the schedule get into RMS?" was one word: SDEF. That is no longer the whole answer, and it changes which export problems you actually have to solve.
What RMS imports now
RMS, the Resident Management System that the Corps of Engineers uses to administer construction contracts, publishes release notes for every patch. Three of them changed the schedule import:
- Patch 444, October 2023. The schedule module, until then called "NAS (SDEF)", was renamed "Network Analysis Schedule (NAS)", and described as "Import P6 XML or SDEF Schedule. Users can import both XML files and SDEF files."
- Patch 555, July 2025. RMS opens native P6
.xerfiles. - Patch 588, January 2026. The screen reads "Import/Export → NAS (SDEF/XML/XER)", and the patch fixes an issue with uploading an XER for the first time.
So in 2026 the import screen lists three formats: SDEF, P6 XML and XER.
What the specification says
The August 2026 edition of UFGS 01 32 01.00 10, the Corps' Project Schedule section, reflects the change. Paragraph 3.11 asks for the schedule data to be uploaded to the "Construction Contract System of Record", and the weekly update to be the progressed "SDEF (or equivalent)" file. It no longer insists on SDEF as the only vehicle.
The SDEF code structure has not gone away. Paragraph 3.3.7 still makes it mandatory:
Use the activity coding structure defined in the Standard Data Exchange Format (SDEF) in ER 1-1-11. This exact structure is mandatory.
So the activity codes the SDEF format defines, including Workers per Day, Responsible Party, Area of Work, Modification Number, Bid Item, Phase of Work, Category of Work and Feature of Work, are required in your schedule whichever file carries it.
What this means for the problems you fix
Some well-known SDEF problems come only from the format's fixed columns:
- descriptions cut to 30 characters,
- calendar names cut to one character,
- a single constraint slot per activity.
If you upload P6 XML or XER, those cuts do not happen. Other requirements come from the specification itself and apply to any file:
- activity IDs of 10 characters or fewer (paragraph 3.12.i),
- the SDEF activity codes and their values (paragraph 3.3.7),
- the P6 settings in paragraph 3.12, such as retained logic and project-level calendars.
It is worth knowing which is which. Shortening every description to 30 characters is wasted work if your contract accepts XER. Missing activity codes are a finding whatever you upload.
What to do
- Ask your Resident Office which file your contract expects. Practice can vary from office to office, and the answer decides which of the format problems apply to you.
- Fix the specification problems regardless: IDs, activity codes and the P6 settings in 3.12.
- If you do upload SDEF, read the converter's log after every export. It lists what was cut or changed.
This article summarises published RMS release notes and specification text. It is not an engineering opinion. Your contract's own specification, and your Contracting Officer, govern what you submit.