The size of the DKIST (formerly ATST) Enclosure, similar to the 8-10 meters class telescopes such as VLT or GTC,
together with the strict and demanding requirement of using the azimuth and shutter movement for accurate positioning
of the entrance aperture stop while tracking, makes it probably the most complex enclosure built up to date. Thus,
managing the system validation becomes a challenging task, in which the singularity of this system has to be considered
by applying customized tools and processes in addition to the usual procedures. This paper describes the managing
process followed towards DKIST Enclosure validation, focused on ensuring final on-site assembly and performance.
During the design phase, the system verification was carried out by means of modeling tools and detailed simulations
and calculations. Furthermore, an overall BIM (Building Information Model) was built to integrate all the design work
and detect potential problems since the design phase; it was used to check interfaces between subsystems, verify
accessibility for maintenance and study the construction process.
The Factory Assembly and Testing phase (FA&T) test campaign, recently finished, has been oriented towards the final
system validation, by testing: 1) the overall system integration; 2) the performance; 3) the simulation of the final on-site
The importance of guaranteeing a correct on-site assembly has driven also the decision towards the installation of a
modular prefabricated cladding, which reduces the risk inherent to the site remoteness and the on-site installation of the
outer water-cooled skin. The validation process also included early prototyping and testing of critical subsystems.
That being said, all this helps reducing the risk significantly during the final on-site assembly and commissioning
through the replication of already validated procedures.