As noted by the 767 driver posting above, the normal hydraulic gear extension system has a backup, "gravity", which occasionally experienced pilots may attempt to assist with maneuvers increasing "G" forces 9especially in smaller, lighter birds used in General Aviation, shaking the gear out of the wells, as it were...

The interesting (and little noted) dramatic visual graphic of the videos is that the a/c essentially "landed' on its engines and pylons with little contact between the fuselage and the runway, demonstrating both purposeful design and extremely strong structural components. To those of us around/in a/c for many decades, the entire incident demonstrates the technical "know how" of the folks who designed and built the a/c, and the steady hand and skills of the guy (or maybe woman) in the left seat, which "says a lot for LOT".

There was a time when pilots were quick to say that any landing after which all the SOBs ("Souls on Board") could walk away was a good one.