yeovil at waR

Flame Fougasse

Weapons of the Home Guard


The most well-known flame weapon devised by the Petroleum Warfare Department (PWD) was the flame fougasse, used and operated by the Home Guard. Originally, a fougasse was a hole in the ground filled with gunpowder and covered with rocks as projectiles, dating back to at least the 16th century. The PWD's modern version comprised up to four camouflaged 40-gallon oil drums dug into the roadside, preferably where vehicles would naturally slow down such as a bend or incline.

In its early incarnations the drums were filled with a 25% petrol and 75% gas oil mixture that would produce a flame 10 feet wide by 30 yards long (3m x 27m) similar to that in the photograph below. The drums were laid on their sides and were usually used in fours, two either side of a road, that would be ignited simultaneously. The fuel mix was later changed to a 40% petrol and 60% gas oil mixture known as 40/60 or 'Standard' mixture. The final development of fuel, known as 5B, was an adhesive gel of tar, lime and petrol that was intended to adhere to a tank and continue burning, thereby cutting off the oxygen supply to both engine and crew.

The flame fougasse, in its early days, had a an 8oz Ammonal charge electrically fired by a No 27 detonator, to blow the front of the drum off and ignite the mixture, and a 5lb charge of gunpowder at the rear of the drum, fired by a No 14 Service Fuse, to propel the burning mixture across the road. This was later changed to just an Ammonal charge at the rear.

Across the country it is estimated that some 50,000 flame fougasse barrels in some 7,000 installations were prepared although none were ever set off in anger. Dozens of flame fougasse sites are known in Somerset.

Adapted from my e-book "A Photographic Guide to the Taunton Stop Line"




The caption to this photograph read "Members of the Yeovil Home Guard burying explosives in the earth bank at Newton Road". In fact they were more likely to be constructing a favourite covert weapon of the Home Guard - a flame fougasse.


A PWD demonstration of a flame fougasse, 1940. At centre is the explosion of the oil drums and to the left is the 30 yard wall of flame that would be projected across the road.