At this time, "it is not known when or if we'll be able to get the site back online." That, according to the owner of www.historycommons.org. It's a technical issue. In the meantime, you can still use the site, and here are the obsessive compulsive ways I have figured out how to do so...

First, go to www.archive.org. In the "Wayback Machine" type in www.historycommons.org

Then it will bring up a "calendar" of dates the site was "memorized" in the "Wayback Machine."

Scrolling to February 2018, and clicking on that gives a link to this version of the site...

https://web.archive.org/web/20180224034530/http://historycommons.org/

The problem is, you can not use "Search" on that site. So, what I've been doing is I click on "Timelines" at the top left of the screen, and then I click on the "Complete 9/11 Timeline," and that brings you here...

https://web.archive.org/web/20180127011151/http://www.historycommons.org/project.jsp?project=911_project

Since I am EXTREMELY familiar with the timeline, this may be a little easier for me, BUT... what I do is I click on "View all events for this timeline (7194)." That takes you to here...

https://web.archive.org/web/20171019210857/http://www.historycommons.org/timeline.jsp?timeline=complete_911_timeline

At the top, you will notice numbers linking to individual pages of the timeline. If you scroll over them, they give you the timeframe for what you're looking for, if you know that kind of thing. Once you find the entry you're looking for, scroll down to the bottom of the entry and look at "Entity Tags," and select the name of the person you are looking for. That will bring you back MOST EVERY entry having to do with that individual.

OR...

You can go back to the main "Complete 9/11 Timeline" page, and click on any of the "Timelines filtered by category" links.

Don't forget that for individual entries you have links to, you can also use the "Wayback Machine" at www.archive.org for those as well.

Hopefully this will help you in the meantime. HOPEFULLY the site will be fixed. I'm hearing that the content of the site MIGHT be recoverable. Keep your fingers crossed. I know I am.