The First Effective Mine Detector

Land mines have been round in a single kind or one other for greater than a thousand years. By now, you’d suppose a easy and protected means of finding and eradicating the gadgets would’ve been engineered. But that’s not the case. In reality, up till World War II, the commonest methodology for locating the explosives was to prod the bottom with a pointed stick or bayonet. The hockey-puck-size gadgets had been buried about 15 centimeters beneath the bottom. When somebody stepped on the bottom above or close to the mine, their weight triggered a strain sensor and brought about the system to blow up. So mine clearing was almost as harmful as simply strolling via a minefield unawares.

During World War II, land mines had been extensively utilized by each Axis and Allied forces and had been answerable for the deaths of 375,000 troopers, in keeping with the Warfare History Network.

In 1941 Józef Stanislaw Kosacki, a Polish alerts officer who had escaped to the United Kingdom, developed the primary moveable system to successfully detect a land mine with out inadvertently triggering it. It proved to be twice as quick as earlier mine-detection strategies, and was quickly in huge use by the British and their allies.

The Engineer Behind the Portable Mine Detector

Before inventing his mine detector, Kosacki labored as an engineer and had developed instruments to detect explosives for the Polish Armed Forces.

After receiving a bachelor’s diploma in electrical engineering from the Warsaw University of Technology in 1933, Kosacki accomplished his year-long necessary service with the military. He then joined the National Telecommunications Institute in Warsaw as a supervisor. Then, as now, the company led the nation’s R&D in telecommunications and knowledge applied sciences. In 1937 Kosacki was commissioned by the Polish Ministry of National Defence to develop a machine that would detect unexploded grenades and shells. He accomplished his machine, but it surely was by no means used within the subject.

Polish engineer Józef Kosacki’s moveable land-mine detector saved hundreds of troopers’ lives in World War II. Military Historical Office

When Germany invaded Poland in September 1939, Kosacki returned to lively obligation. Because of his background in electrical engineering, he was positioned in a particular communications unit that was answerable for the maintenance of the Warszawa II radio station. But that obligation lasted solely till the radio towers had been destroyed by the German Army a month after the invasion.

With Warsaw underneath German occupation, Kosacki and his unit had been captured and brought to an internment camp in Hungary. In December 1939, he escaped and finally discovered his solution to the United Kingdom. There he joined different Polish troopers within the 1st Polish Army Corps, stationed in St. Andrews, Scotland. He educated troopers in using wi-fi telegraphy to ship messages in Morse code.

Then tragedy struck.

Tragedy Inspired Engineering Ingenuity

The invention of the moveable mine detector happened after a horrible accident on the seashores of Dundee, Scotland. In 1940, the British Army, fearing a German invasion, buried hundreds of land mines alongside the coast. But they didn’t notify their allies. Soldiers from the Polish tenth Armored Cavalry Brigade on a routine patrol of the seaside had been killed or injured when the land mines exploded.

This occasion prompted the British Army to launch a contest to develop an efficient land-mine detector. Each entrant needed to cross a easy check: Detect a handful of cash scattered on the seaside.

Kosacki and his assistant spent three months refining Kosacki’s earlier grenade detector. During the competitors, their new detector situated the entire cash, beating the opposite six gadgets entered.

There’s some murkiness concerning the detector’s actual circuitry, as befits a expertise developed underneath wartime safety, however our greatest understanding is that this: The device consisted of a bamboo pole with an oval-shaped picket panel at one finish that held two coils—one transmitting and one receiving, in keeping with a 2015 article in Aerospace Research in Bulgaria. The soldier held the detector by the pole and handed the picket panel over the bottom. A picket backpack encased a battery unit, an acoustic-frequency oscillator, and an amplifier. The transmitting coil was linked to the oscillator, which generated present at an acoustic frequency, writes Mike Croll in his e book The History of Landmines. The receiving coil was linked to the amplifier, which was then linked to a pair of headphones.

The detector weighed lower than 14 kilograms and operated very like the metallic detectors utilized by beachcombers immediately. Michał Bojara/National Museum of Technology in Warsaw

When the panel got here near a metallic object, the induction steadiness between the 2 coils was disturbed. Via the amplifier, the receiving coil despatched an audio sign to the headphones, notifying the soldier of a possible land mine. The gear weighed slightly below 14 kilograms and could possibly be operated by one soldier, in keeping with Croll.

Kosacki didn’t patent his expertise and as an alternative gave the British Army entry to the system’s schematics. The solely recognition he obtained on the time was a letter from King George VI thanking him for his service.

Detectors had been rapidly manufactured and shipped to North Africa, the place German commander Erwin Rommel had ordered his troops to construct a defensive community of land mines and barbed wire that he known as the Devil’s Gardens. The minefields stretched from the Mediterranean in northern Egypt to the Qattara Depression in western Egypt and contained an estimated 16 million mines over 2,900 sq. kilometers.

Kosacki’s detectors had been first used within the Second Battle of El Alamein, in Egypt, in October and November of 1942. British troopers used the system to scour the minefield for explosives. Scorpion tanks adopted the troopers; heavy chains mounted on the entrance flailed the bottom and exploded the mines because the tank moved ahead. Kosacki’s mine detector doubled the pace at which such closely mined areas could possibly be cleared, from 100 to 200 sq. meters an hour. By the top of the conflict, his invention had saved hundreds of lives.

Kosacki’s land-mine detector was first utilized in Egypt, to assist clear a large minefield laid by the Germans. The primary expertise continued for use till 1991.National Army Museum

The primary design with minor modifications continued for use by Canada, the United Kingdom, and the United States till the top of the First Gulf War in 1991. By then, engineers had developed extra delicate moveable detectors, in addition to remote-controlled mine-clearing techniques.

Kosacki wasn’t publicly acknowledged for his work till after World War II, to stop retribution towards his household in German-occupied Poland. When Kosacki returned to Poland after the conflict, he started educating electrical engineering on the National Centre for Nuclear Research, in Otwock-Świerk. He was additionally a professor at what’s now the Military University of Technology in Warsaw. He died in 1990. The prototype of Kosacki’s detector proven at prime is housed on the museum of the Military Institute of Engineering Technology, in Wroclaw, Poland.

Land Mines Are Still a Worldwide Problem

Land-mine detection has nonetheless not been perfected, and the explosive gadgets are nonetheless an enormous downside worldwide. On common, one particular person is killed or injured by land mines and different explosive ordnance each hour, in keeping with UNICEF. Today, it’s estimated that 60 international locations are nonetheless contaminated by mines and unexploded ordnance.

Although moveable mine detectors proceed for use, drones have grow to be one other detection methodology. For instance, they’ve been utilized in Ukraine by a number of humanitarian nonprofits, together with the Norwegian People’s Aid and the HALO Trust.

Nonprofit APOPO is taking a distinct strategy: coaching rats to smell out explosives. The APOPO HeroRATs, as they’re known as, solely detect the scent of explosives and ignore scrap metallic, in keeping with the group. A single HeroRAT can search an space the dimensions of a tennis court docket in half-hour, as an alternative of the 4 days it might take a human to take action.

Part of a persevering with sequence taking a look at historic artifacts that embrace the boundless potential of expertise.

An abridged model of this text seems within the January 2025 print situation as “The First Land-Mine Detector That Actually Worked.”