Canadian pipe mine
Encyclopedia
The Canadian pipe mine, also known as the McNaughton tube, was a type of landmine deployed in Britain during the invasion crisis of 1940-1941
. It comprised a horizontally bored
pipe packed with explosives, and once in place this could be used to instantly ruin a road
or runway
thereby denying its use by an enemy.
under the command of Lieutenant-General Andrew McNaughton
arrived in England in December 1939. They were not initially sent to France with the British Expeditionary Force
(BEF) and therefore were not caught up in the escape from Dunkirk, although they were very briefly deployed to Brest
in north-western France. On their return the No 1 Tunnelling Company, Royal Canadian Engineers were employed in the preparation of field fortifications along the south coast of England. In this company were a number of men from British Columbia
, the rugged and mountainous, westernmost province of Canada. Many of these men were highly skilled in the use of diamond-tipped bits for drilling into hard rock.
Somebody realised that the lightweight drilling rigs and pipe pushing machines could easily be adapted to the soft soils and sedimentary rocks of southern England and that the rigs themselves could easily be transported on the back of a truck or a road grader fitted with a steel platform. Soon, such rigs were being used to drill into the approaches to bridges or embankments, the pipe being left in the ground and filled with explosives ready for instantaneous demolition
.
This idea was further developed to make an invisible anti-tank obstacle. The drills and pipe punching machines were used to bury a series of 3 inches (7.6 cm) diameter pipes, each at a shallow angle to a maximum depth of about 8 feet (2.4 m). Each pipe was about 55 feet (16.8 m) long and they were placed at intervals of 25 feet (7.6 m) in an overlapping pattern. The pipes were packed with explosives which when detonated would produce a very effective anti-tank obstacle about 28 feet (8.5 m) wide and 8 feet (2.4 m) deep with loose soil at the bottom.
Conventional anti-tank obstacles were very obvious from the air. These pipe mines had the advantage of being virtually invisible from the air and so could be used when the enemy had been coaxed into a seemingly weak point in the defences. Furthermore, the mines could be set in place without interference to the normal use of the land and so they were deployed under roads and railways that might need to be blocked in an instant, and runways that may need to be denied to the enemy at short notice.
Originally known as the Canadian Pipe Mine, it was later named the McNaughton Tube Tank Obstacle in honour of the commander of the Canadian Corps, Lieutenant-General Andrew McNaughton.
On 9 August 1940, "McNaughton’s secret A/T obstacle" was demonstrated to General Brooke and met with enthusiastic approval. By October 1940, the skills of the Canadian engineers were in demand and consideration was being given to training further British units to install the devices. In due course, 179 Special Tunnelling Company of the Royal Engineers was formed. About 40000 feet (12.2 km) of the obstacle were installed – requiring some 90 tonnes of explosives.
explosives would remain potent for several years, by the spring of 1941 it was evident that the explosives in some of the tubes had been affected by water and its power had deteriorated significantly. A brass spearhead on a long rod was provided for withdrawing the explosives from the tubes, but in some cases the explosive had deteriorated into a porridge-like mush. Second Lieutenant Cameron, who as a civilian was a very experienced oil drilling engineer, suggested washing out the explosives with water delivered by a narrow diameter tube pushed down the main pipe. The mush, along with globules of nitro-glycerine was caught in hessian sacks and disposed of. The original pipes were then re-charged with more stable explosives.
Soon after the end of the war, almost all the Canadian pipe mine installations were removed. However, a small number were missed and rediscovered many years later when it was necessary to deal with them with great care. This happened in April 2006 when 20 unexploded pipe mines were discovered under a runway at a former Royal Navy
air base, HMS Daedalus
, Lee-on-Solent, Hampshire
. 60 feet long, they were left over from an original 265, packed with a total of 2,400 lb of explosive. Their removal, thought to be the largest of its kind in peacetime Britain, led to the evacuation of some 900 homes staggered over a 5 week period. The mines were destroyed by controlled explosion.
British anti-invasion preparations of World War II
British anti-invasion preparations of the Second World War entailed a large-scale division of military and civilian mobilisation in response to the threat of invasion by German armed forces in 1940 and 1941. The British army needed to recover from the defeat of the British Expeditionary Force in...
. It comprised a horizontally bored
Directional drilling
Directional drilling is the practice of drilling non-vertical wells. It can be broken down into three main groups: Oilfield Directional Drilling, Utility Installation Directional Drilling Directional drilling (or slant drilling) is the practice of drilling non-vertical wells. It can be broken down...
pipe packed with explosives, and once in place this could be used to instantly ruin a road
Road
A road is a thoroughfare, route, or way on land between two places, which typically has been paved or otherwise improved to allow travel by some conveyance, including a horse, cart, or motor vehicle. Roads consist of one, or sometimes two, roadways each with one or more lanes and also any...
or runway
Runway
According to ICAO a runway is a "defined rectangular area on a land aerodrome prepared for the landing and take-off of aircraft." Runways may be a man-made surface or a natural surface .- Orientation and dimensions :Runways are named by a number between 01 and 36, which is generally one tenth...
thereby denying its use by an enemy.
Development
The Canadian 1st Division1st Canadian Infantry Division
The 1st Canadian Infantry Division was a formation mobilized on 1 September 1939 for service in the Second World War. The division was also reactivated twice during the Cold War....
under the command of Lieutenant-General Andrew McNaughton
Andrew McNaughton
General Andrew George Latta McNaughton, CH, CB, CMG, DSO, CD, PC was a Canadian army officer, politician and diplomat.- Early life :...
arrived in England in December 1939. They were not initially sent to France with the British Expeditionary Force
British Expeditionary Force (World War II)
The British Expeditionary Force was the British force in Europe from 1939–1940 during the Second World War. Commanded by General Lord Gort, the BEF constituted one-tenth of the defending Allied force....
(BEF) and therefore were not caught up in the escape from Dunkirk, although they were very briefly deployed to Brest
Brest, France
Brest is a city in the Finistère department in Brittany in northwestern France. Located in a sheltered position not far from the western tip of the Breton peninsula, and the western extremity of metropolitan France, Brest is an important harbour and the second French military port after Toulon...
in north-western France. On their return the No 1 Tunnelling Company, Royal Canadian Engineers were employed in the preparation of field fortifications along the south coast of England. In this company were a number of men from British Columbia
British Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...
, the rugged and mountainous, westernmost province of Canada. Many of these men were highly skilled in the use of diamond-tipped bits for drilling into hard rock.
Somebody realised that the lightweight drilling rigs and pipe pushing machines could easily be adapted to the soft soils and sedimentary rocks of southern England and that the rigs themselves could easily be transported on the back of a truck or a road grader fitted with a steel platform. Soon, such rigs were being used to drill into the approaches to bridges or embankments, the pipe being left in the ground and filled with explosives ready for instantaneous demolition
Demolition belt
In military terminology, a demolition belt is a selected land area sown with explosive charges, mines, and other available obstacles to deny use of the land to enemy operations, and as a protection to friendly troops.There are two types of demolition belt:...
.
This idea was further developed to make an invisible anti-tank obstacle. The drills and pipe punching machines were used to bury a series of 3 inches (7.6 cm) diameter pipes, each at a shallow angle to a maximum depth of about 8 feet (2.4 m). Each pipe was about 55 feet (16.8 m) long and they were placed at intervals of 25 feet (7.6 m) in an overlapping pattern. The pipes were packed with explosives which when detonated would produce a very effective anti-tank obstacle about 28 feet (8.5 m) wide and 8 feet (2.4 m) deep with loose soil at the bottom.
Tactical use
A secret report emphasised the value of this obstacle:Conventional anti-tank obstacles were very obvious from the air. These pipe mines had the advantage of being virtually invisible from the air and so could be used when the enemy had been coaxed into a seemingly weak point in the defences. Furthermore, the mines could be set in place without interference to the normal use of the land and so they were deployed under roads and railways that might need to be blocked in an instant, and runways that may need to be denied to the enemy at short notice.
Originally known as the Canadian Pipe Mine, it was later named the McNaughton Tube Tank Obstacle in honour of the commander of the Canadian Corps, Lieutenant-General Andrew McNaughton.
On 9 August 1940, "McNaughton’s secret A/T obstacle" was demonstrated to General Brooke and met with enthusiastic approval. By October 1940, the skills of the Canadian engineers were in demand and consideration was being given to training further British units to install the devices. In due course, 179 Special Tunnelling Company of the Royal Engineers was formed. About 40000 feet (12.2 km) of the obstacle were installed – requiring some 90 tonnes of explosives.
Problems
However, all was not well with the McNaughton tubes. Although it had been thought that the blasting gelatineGelignite
Gelignite, also known as blasting gelatin or simply jelly, is an explosive material consisting of collodion-cotton dissolved in either nitroglycerine or nitroglycol and mixed with wood pulp and saltpetre .It was invented in 1875 by Alfred Nobel, who had earlier invented dynamite...
explosives would remain potent for several years, by the spring of 1941 it was evident that the explosives in some of the tubes had been affected by water and its power had deteriorated significantly. A brass spearhead on a long rod was provided for withdrawing the explosives from the tubes, but in some cases the explosive had deteriorated into a porridge-like mush. Second Lieutenant Cameron, who as a civilian was a very experienced oil drilling engineer, suggested washing out the explosives with water delivered by a narrow diameter tube pushed down the main pipe. The mush, along with globules of nitro-glycerine was caught in hessian sacks and disposed of. The original pipes were then re-charged with more stable explosives.
Soon after the end of the war, almost all the Canadian pipe mine installations were removed. However, a small number were missed and rediscovered many years later when it was necessary to deal with them with great care. This happened in April 2006 when 20 unexploded pipe mines were discovered under a runway at a former Royal Navy
Royal Navy
The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...
air base, HMS Daedalus
HMS Daedalus
Royal Naval Air Station Lee-on-Solent was one of the primary shore airfields of the Fleet Air Arm. First established as a seaplane base in 1917 during the First World War, it later became the main training establishment and administrative centre of the Fleet Air Arm...
, Lee-on-Solent, Hampshire
Hampshire
Hampshire is a county on the southern coast of England in the United Kingdom. The county town of Hampshire is Winchester, a historic cathedral city that was once the capital of England. Hampshire is notable for housing the original birthplaces of the Royal Navy, British Army, and Royal Air Force...
. 60 feet long, they were left over from an original 265, packed with a total of 2,400 lb of explosive. Their removal, thought to be the largest of its kind in peacetime Britain, led to the evacuation of some 900 homes staggered over a 5 week period. The mines were destroyed by controlled explosion.
See also
- British anti-invasion preparations of World War IIBritish anti-invasion preparations of World War IIBritish anti-invasion preparations of the Second World War entailed a large-scale division of military and civilian mobilisation in response to the threat of invasion by German armed forces in 1940 and 1941. The British army needed to recover from the defeat of the British Expeditionary Force in...
- British hardened field defences of World War IIBritish hardened field defences of World War IIBritish hardened field defences of World War II were small fortified structures constructed as a part of British anti-invasion preparations. They were popularly known as pillboxes by reference to their shape.-Design and development:...
- CamoufletCamoufletA camouflet, in military science, is an artificial cavern created by an explosion. If the explosion reaches the surface then it is called a crater....