Text Edit rtf. Document suddenly disappeared from desktop after opening it! A very important (30+ hrs. of work) Text Edit rtf. Document suddenly disappeared from desktop after opening it!

I have been working on a translation with a tight deadline; non-stop working for 5 days all day, everyday.
I boarded a plane today, and before take-off, I took my computer out to continue working on the document. 

The document/file was saved on my desktop. I open it, and scroll through it. Then I open another file, and another photograph file (all were saved on the Desktop)... All of a sudden, my translation 16 page document FILE IS GONE. 
Literally gone and disappeared like it never existed! The document was gone, the icon on the desktop was gone... everything!
I tried checking in Trash, nothing. I checked "Open Recent" in Text Edit, and older documents were there, but no sign of my translation document. 
I searched my entire computer. Nothing. It's like as if it never existed and this is tearing me apart. 

I can't write to my job commission that, "hey my computer had a technical glitch and my file disappeared"... and this job is very important to me, as it will pay some important bills and I am really devastated about this setback and all the hard work I poured into this translation and now its just simply gone?? How on earth can this be?!! I really truly and deeply appreciate anyone who can help me out... thanks so much.
Local Time Machine snapshot
If you enabled Time Machine and didn't disable local snapshots in the past (but can't back up your files at the moment because the backup volume is at home/elsewhere) you should be able to find the file in the local Time Machine snapshot.

Open Time Machine
In the &quot;Star Wars&quot; display navigate to your desktop folder
White/purple ticks at the right side indicate local snapshots/snapshots on the Time Machine backup volume
Use the white ticks to search for your lost document

Containers
A second place to find the file - independent of any backups - may be:
/Users/your_user_name/Library/Containers/com.apple.TextEdit/Data/Library/Autosave Information/