Tech hat on - the BIOS version dates to 8 April 2010 so somebody was maintaining it. I assume the battery has been replaced periodically but, possibly due to COVID, not recently enough.
Geek hat on - the museum is awesome. Totally different feel versus the Air and Space Museum downtown. A must see.
At the moment you need to reserve a free ticket (to control crowds). As COVID restrictions are lifted, aside from the exhibits, there is the previously mentioned observation tower and an IMAX theater..
BTW, as far as the jet engines, like the planes, they are fully restored and are displayed separately so they can be fully viewed.