With a flail, they didn’t need to be cleared later!
You’d think...
But flails were dropped post WW2 because they are (a) slow and (b) you can’t fire the main armament whilst you’re using them. The are also loud. Anyone who’s been in a maggot at night on Soltau etc will know that although you can hear that tanks are moving around, it’s not easy to pinpoint exactly where they are. BFO AT mines detonating will be a bit of a giveaway...
Also, if you read some of the stories in ‘Churchill’s Secret Weapons’ you’ll see that flails weren’t 100% reliable. This is because they form a cylinder of force as they rotate. Great on a football pitch (or a runway!) but they will skip over any irregularities. Mines in a hole or behind a rock can be missed. Flails also LOVE barbed wire. To be fair, in Normandy this still gave you better odds then leopard crawling up a beach with a bayonet.
Furthermore the advent of double-impulse fuzes (originally intended to defeat rollers) such as the British No 5 Fuze, and blast resistant mines (such as the VS50 and the PMN2 AP mines, and their AT equivalents) reduces the effectiveness of flails to about 50%, as I can personally attest to after operational trials in a number of countries. They also have a bad habit of throwing out these still-live mines into previously cleared area.
From a purely military perspective, mine ploughs* are still the best option for rapid breaching.
Flails do have a place, but it’s mainly for proving an area where mines aren’t...
* Americans please note correct spelling
