Which document control system supports immutable records and revision control for aerospace maintenance files?

A document management / PLM system with audit trails and versioning is typically required for aerospace maintenance files.

If you mean a specific system that supports immutable records and revision control, look for one that provides:

• Write-once / immutable storage for finalized records
• Full revision history with check-in/check-out
• Audit trails showing who changed what and when
• Electronic signatures and approval workflows
• Retention and compliance controls for aviation records

Common enterprise systems used in regulated aerospace environments include:

• MasterControl
• OpenText Extended ECM
• Veeva Vault (more life sciences, but similar compliance model)
• DocuWare / M-Files with proper governance setup
• Aerospace-focused PLM/DM platforms such as Siemens Teamcenter or PTC Windchill

If you want, I can help identify the best-fit system for FAA/EASA maintenance record compliance or compare a few options.