Ploughshare Innovations recently licensed door-breaching grenade technology developed by a Dstl scientist to explosives specialist company Energetics Technology. Berenice Healey explores how it aims to improve explosive method of entry operations without compromising on safety.

The design enables the blast to be highly targeted, meaning less explosive is needed, reducing stand-off distance and lowering the risk to the breaching team and anyone behind the door due to reduced fragmentation. It works by deforming doors – even the strongest including multi-lock steel doors – weakening the hinges to enable access by the breaching team.

The technology is based around 40mm grenades, which are deployed in several roles as marking rounds and offensive rounds and has been seen as a potentially useful tool to be able to deploy a door breaching capability.

ETL managing director Dr Peter Jemmett explains: “This allows the user to engage a potentially hostile environment from a safe distance and allows other users who may be close to remain safe until they can fully understand what's behind the door – what threat is present – and then they'll take appropriate action.”

Previous 40mm door breaching systems have ranged from small, simple payloads that will, if targeted correctly, cause localised damage to locks and hinges. At the other extreme, large payloads take the door off its hinges but can also destroy the surrounding wall.

“The downside of that is simply blowing a hole in the door doesn't achieve what you need, tactically,” Jemmett says. “You need that door to be a fully-opened aperture so that you can get your troops inside.”

Thornhill came up with the design when he was evaluating door breaching products for Dstl. He discovered that current designs tend to make holes in the door rather than open it and often take multiple attempts to breach it. They were largely adapted from products that are supposed to go through things rather than open doors and therefore have some design issues.

The new design features a block of explosive in the middle, with an initiation system or a detonator at the back and a gap at the front end. This offers a standoff distance between your explosive charge, and the target, which, in combination with the geometry of the explosive charge, gives a unique effect.

“It sounds very obvious, but when explosives are placed up against something, they tend to break it very easily,” explains Jemmett. “The further that explosive is away from that target, you change the mechanism of delivering energy into that target. Rather than shattering it into pieces and blowing the hole, by increasing the standoff and controlling the shape of how the gases are formed and the pressure waves generated, you can cleverly apply very high-pressure waves in a very controlled manner.”

The next stage is taking the innovation and developing it into a commercially viable product.

Ploughshare Innovations commercial director and VP business development Gordon Scott explains: “Having sketched out an idea on a piece of paper, the patent attorney went away to see whether we thought it was novel and protectable in that manner, and Thornhill went away to develop his ideas and got funding from Dstl to do some modelling and check users would be interested in this principle.

“Ploughshare was tasked at that point to investigate whether there was a wider market and a commercial need. The three parties all came back with positives; there was novelty in the invention, the original simulations were promising, and there was positive feedback from the user community.”

Having identified an MOD need and a commercial market for the product, the team carried out further trials and Dstl received funding from the MOD’s chief scientific adviser to do static trials then live-fires. The technology patent has been granted in the UK and is pending in other territories.

Scott adds: “ETL took the licence early this year after about two or three years of work, taking it through the patenting route and development trials. It has now started to turn what is a reasonably high technical readiness level prototype into a product that you can sell in volume. Hopefully, the MOD and other UK users will buy some; it’s also is available to Europe, Australia and New Zealand.”

ETL launched the breaching technology through a sister company at the Special Forces show in France in June. The company is now in the process of finalising the design and purchasing materials to produce a batch to supply the market for the next 12 months, despite Brexit and Covid affecting the lead time.

“We already have a contract to supply a UK customer with this for their initial evaluations that we're expecting that to be completed in September or October,” says Jemmett.

“We'll take the feedback, and it will lead to the next iteration of product design. It will take three to four months for these various users to assess against their particular operating procedures and threats. That's when we go from initial evaluation quantities to accepted in service and routine procurements.”

// Main image: The innovative door-breaching grenade detonates at a safe distance to blow a door off its hinges. Credit: MOD/Ploughshare, crown copyright.