what is a gravity knife

A gravity knife is a knife with a blade contained in its handle, and which opens its blade by the force of gravity. As the gravity knife requires gravity or rotary motion to propel the blade out of the handle, it differs fundamentally from the switchblade knife , which opens its spring-loaded blade automatically at the press of a button, switch, or fulcrum lever. The main purpose of this opening method is that it allows opening and closing with one hand., in situations where the other hand is busy. Thus, they have historically been issued to skydivers for cutting trapped lines, such as lines tangled in trees, an important potential use of the gravity knife.

The gravity knife uses a button, trigger, or fulcrum lever to release the blade from both the open and closed positions, and can use either a side-folding or telescopic (outward-facing, or OTF) blade. While most military gravity knives use a locking blade design, other types may not lock mechanically, but rely on friction to wedge the rear section of the blade against the inside of the handle. Factory-made gravity knives have various types of buttons, triggers, and fulcrum levers, which are typically used to release the blade from both the open and closed positions.

Design and operation

Flieger – Kappmesser / Luftwaffe (LGK) gravity knife

One of the most recognizable gravity knives is the World War II -era Flieger-Kappmesser ( literally: “flyer cutting knife”), which uses a four-inch (100 mm) powered telescopic locking (OTF) blade. by gravity. First produced in 1937, the often called Fallschirmjägermesser was initially issued to German paratroopers and flight crews, primarily for the purpose of cutting a trapped paratrooper off his rig should he land with an entangled parachute or become entangled in trees. or in the water. with the lines of the mortise. The spike was used to untie knots while packing parachutes. Luftwaffe aircrew members used the knife to remove their harnesses or cut through the aircraft’s aluminum hull after a crash landing. Although not intended for use as a combat knife in the first place, the LGK was introduced to the 1st Skijäger Division and SS units on the Eastern Front to be used primarily as a close combat weapon beginning in 1944.

The Flieger-Kappmesser uses a sliding blade within a metal grip frame, which was originally fitted with smooth wooden scales. The blade itself is a relatively blunt spear point , and the profile is flat and tapers to a utility edge. To open the blade, the user points the knife downward while lifting the fulcrum-style operating lever, allowing gravity to draw the blade to its full extension. Releasing the lever locks the blade in position. The LGK can also be opened by turning the blade release lever while moving the wrist holding the knife, causing the blade to extend. The LGK was also fitted with a folding marlinspike or punch . Primarily intended for untangling rope knots, it was also used as a prying tool or to fix stuck weapons. The tip does not lock when opened and was never intended to be used as a combat weapon.

There are two main types of wartime Flieger -Kappmesser with a total of 10 known variations. The Type I LGK (three manufacturers, five WWII variations) has wooden scales (handle), was made between 1937 and 1943, and unlike successive models has no “take-down” capability. The LGK Type II (two makers, five WWII variations) is the same knife, but with takedown features, and was produced from 1943 to 1945 and then again from ca. 1950 to 1965.

After the end of World War II, the newly organized West German Bundeswehr placed new orders with German cutlery manufacturers for a post-war version of the Kappmesser to be issued to Army airborne forces and tank crews. The Luftwaffe ofWest Germany abandoned the gravity knife concept entirely and bought entirely different salvage knives, including a deck line cutter. The Type III “trapdoor” initial gravity knife, manufactured between 1955 and 1961 did not prove to be very reliable and so the original WWII Type II design was reintroduced until finally superseded by the earliest knives. type IV in approx. 1968. The Type IV LGK is very similar to the WWII production Type II takedown knife, but features plastic polymer instead of wood flakes and was manufactured by WMF, OFW and Eickhorn from 1972-1984.

They were handed over to the soldiers of the Bundeswehrto 2017. West Germany’s third post-war model is the LGK Type V, initially named AES79 and still produced under the designation LL80 (1979–present) by Eickhorn today. The LL80 is smaller, has fewer parts, and is more cost-effective to produce than the earlier Flieger-Kappmesser . It was purchased by the Swiss Air Force and issued to their Dassault Mirage pilots in 1983. These knives are marked AES83 and bear the aircraft number on the metal head.

On the other side of the Iron Curtain , in the German Democratic Republic , World War II Gravity Knives were reconditioned and reissued to paratroopers and pilots until existing stocks were depleted. In the early 1960s, two companies produced an East German version of Type I knives. They were then used until the early 1970s.

ibberson gravity knife

After numbers of Flieger-Kappmesser Type I were captured by British forces , the British government approached George Ibberson & Co. of Sheffield , England, a manufacturer of knives and cutlery, and requested production of a British version of the gravity knife. German Luftwaffe for special operations. Executive (SOE) and other clandestine warfare units. Under the initial wartime contract, George Ibberson & Co. manufactured 500 gravity knives for issue to SOE and other special forces. These Sheffield gravity knives had smooth wood or textured plastic scales, but were otherwise identical in features and operation to the Flieger-Kappmesser.Type I, with a gravity-deployed locking blade and a collapsible spike or pick. In the hands of British SOE agents, the Sheffield gravity knife was considered a secondary combat weapon. In addition to the knife blade, SOE melee instructors found the collapsible rigging spike useful for silently killing sentries by opening the carotid artery in the neck.

Fake Gravity’ and Non-Gravity Knives

Some folding or telescoping knives that can open their blades by the force of inertia or gravity were not designed or advertised by the manufacturer to do so. Knives that lock their blades open, but do not have any closed position locking devices, are called “false” gravity blades.

Illustration shows the internals of a 1960s Japanese import ‘fake’ gravity knife. Other knives may be considered ‘fake’ gravity knives, including certain back-lock and liner-lock folding knives that do not lock a blade in the open and closed positions.

After the passage of the Switchblade Knife Act in the US in 1958, it was discovered that some American companies were importing folding stiletto knives without spring mechanisms that did not have a pronounced blade heel (inner surface) on the area pivot which allowed the 11 and 13 inch blade models to open easily. Modern (post-1965) folding stilettos imported or distributed in the US now have blade studs that are intentionally pointed and against the locking mechanism, preventing inertial opening.

Other blades commonly confused with gravity knives include the automatic OTF knife , the switchblade and butterfly knife (or balisong), the slide knife , penny knife , and even occasionally common folding hunting knives such as the buck. 110 Folding Hunter.