"Jay Smith" wrote in message news
I do not recall what the limitations are, so I was hoping there was a
website where they could be found. I know there are some oil canning
issues in flight with the door(s) removed on some aircraft.

The limitations are whatever the authority you have to remove the door is.
As pointed out, it must be supported by the original operating limitations, or
through an STC or special approval.

The fact that certain jump zones operate illegally is not surprising...a crash here
in 1975 was attributed to bogus W&B info from unauthorized skydiving mods
to a Queen Air including seat and door removal.