This is from their “About” page:
We serve the public interest in providing educational resources freely in the fields of scientific inquiry. Principia Scientific International CIC is about transparency and truth; the only publishing international science association shunning political advocacy and defending the traditional scientific method, as extolled by Karl Popper.
The essence of genuine scientific inquiry shall exemplify the sui generis, or the abiding maxim that goodness is indefinable and exists in science only insofar as the pursuit of truth ought to be our abiding goal.
Our members feel a moral duty to preserve the traditional methods of open scientific inquiry free from persecution, ridicule and censure.
While they only have one article directly relating to 9/11, they have dozens of articles of interest to our community.