Yes, if you drop an old-style 1911 on its muzzle from a sufficient height with a round chambered, it will fire. However, it will do this whether or not the safety is on or the slide is locked, so I don't think that is the case. By the way, this was the reason Colt added the firing pin safety to the 1911A1 design (series 80s guns).
Originally Posted by ScottChapin
There may have been concerns about the slide being pushed back out-of-battery just far enough to prevent firing, perhaps during holstering or CQB/mounted operations. The slide locking function WOULD prevent that type of stoppage, which can sometimes be very difficult to detect ahead of time.
"Placement is power" -- seen in an article by Stephen A. Camp
(RIP, Mr. Camp; you will be remembered, and missed)