If they somehow managed to eject off the jet, and after landing, the knife helped them to cut the ropes since it’s the comparatively faster process then getting out of the parachute in order to save the life from the enemies. If the jet crashed for any reason, the pilot would use the gravity knife to cut aluminum to escape from the wreck. This knife was first used in the world war by the parachutists and the fighter jet pilots. The button releases the blade and it comes out of the shell. To open the blade, you only need to point the knife downward, the gravity works the rest.
In Fallschirmjägermesser, the side blade is originally fitted with a smooth wooden scale. The blade is sharp which cuts out hard ropes or aluminum with just a stroke. The Best gravity knife contains the sliding blade which is fitted with smooth scales. Its main purpose was to cut the ropes of the stuck parachutists in case of tangled ropes in trees of parallel circumstances. It was first provided to German soldiers and parachutists. The Fallschirmjägermesser was the first gravity knife invented in 1937. This makes it the best knife that is widely used in the military. The gravity best knife has an edge over other knives that it has the ability to release the blade from both sides, open and closed position. The only thing you need to do is just press the trigger or a fulcrum liver and the knife will come out itself without pulling the knife out manually. This gravity knife makes their work easier since it pops out without any effort. This Knife is used by the parachutists to cut off their parachute or ropes if, due to any circumstances, they are stuck somewhere.