hard stop

• hard-stop

hard stop (plural hard stops)

1. A mechanical device that limits the travel of a mechanism.
2. A definite time when someone must end a task; a non-negotiable deadline.

   I have a hard stop at 4 pm, so please try to cover everything in the meeting before then.

3. A tactic used by armed police to stop a vehicle believed to contain dangerous criminals.
4. Synonym of full stop

• Roskam's Airplane War Stories: An Account of the Professional Life and Work By Jan Roskam p.235 Google Books: http://books.google.com/books?id=rBksUk40jlEC&pg=PA235&lpg=PA235&dq=%22flight+control%22+%22hard+stop%22&source=bl&ots=oMdW932TpF&sig=A2Egw9_kq91foLx5QAxzPQgv70s&hl=en&ei=hrpKTuT6E8fn0QGd7YzsBw&sa=X&oi=book_result&ct=result&resnum=2&sqi=2&ved=0CBwQ6AEwAQ#v=onepage&q=%22flight%20control%22%20%22hard%20stop%22&f=false
• BBC News: How do the police carry out a 'hard stop'? https://www.bbc.co.uk/news/av/uk-25373505

• hardtops, potshard