Andy Smith
MIne-action specialist
Machines in HD, part 1


What follows is the PowerPoint presentation named "Mechanical assistance", formatted as a scrolling webpage.

Humanitarian Demining

Part 10: Machines in HD, section 1

Mechanical assistance




The most common mechanical assistance in Humanitarian Demining is the ubiquitous 4x4 truck - from basic ex-army Landrovers to fully equipped Landcruisers. They are not just transportation. The picture above shows one being used as a display board for Mine Risk Education posters. While being the most favoured vehicle for ex-pat travel, they are also often converted to serve as site ambulances.

Despite the IMAS requirements, ambulances vary from unconverted Landrovers and open trucks to purpose adapted vehicle. The makeshift approach of some groups is probably because accidents are so rare that they resent investing in dedicated vehicles. Occasionally, helicopters may also be used for MEDEVAC but this usually only occurs where there is a helicopter facility provided by a UN MAC. In Cambodia, CMAC have found it cost effective to contract a helicopter service rather than provide an ambulance for every site.

Depending on the number of personnel involved, the actual deminers may deploy in 4x4s. When teams are large, they may deploy in trucks of buses.

This picture shows the demining group MCPA deploying in buses in Afghanistan.

And this shows an NPA team preparing to leave for work in Angola.

In a very few cases, the deminers may be transported in MPVs (Mine Protected Vehicles) - but usually only when the MPV has another use in the mined area. Recent events in Afghanistan and Iraq have led to a demand for many more MPVs, primarily because the clearance personnel may be seen as a legitimate target by some of the combatants. This is not normal in HD.

These pictures show the Zimbabwe army deploying in an MPV - but they were working in an AP mine area and used the vehicle because it was one of the few that was running rather than for protection. Developed during the Rhodesian war for independence by the defenders, notice the vehicle's "V" shaped sides and the absence of mudguards. These features are discussed later under Part 3, Armouring.

Although it is not normal in HD for the deminers to be deliberately targeted, mine accidents with 4x4s do occur.

A Nissan after hitting an AT mine at slow speed (in reverse while parking) in Angola.

A Toyota after clipping an AT mine with a rear wheel in Afghanistan.

Another Toyota, this time in Angola. The vehicle was fitted with "after-market" armour floor blankets - that were entirely ineffective. (You are looking at a crushed doorway.)

A Landrover in Eritrea… the AT mine burst it open. (The wheel at the rear is actually attached to the back door.)

And a HMVEE in Afghanistan.

These pictures show that there are explosive risks involved in merely getting to work…. But there are many more normal Road-Traffic-Accidents involving deminers than explosive events. In many countries there is a good argument for using MPVs whenever possible, but only because the occupants would be safer in a conventional traffic accident as well. While they are expensive, reconditioned MPVs probably cost less than you expect, but the running costs can be very high.


Clearing undergrowth

The most common reason for a deminers death while engaged in mine-clearance (as opposed to stockpile destruction and handling ordnance) is while cutting undergrowth in areas where there are bounding fragmentation mines. This is not only because of the threat from tripwires, but also the threat from tilt-sensitive fuzes standing up amid the undergrowth.

This picture shows the fuze of a PROM-1

The most common form of mechanical assistance to the actual deminer is the clearing of undergrowth in advance of their work. This may be done with "cutters", "mulchers" or "flails" attached to large or small machines. The main difference is that "cutters" and mulchers are not designed to impact the ground. Most flails are designed to strike the ground, and some cannot be deployed without doing so because the flail-head overruns unless there are impacts to slow it down.

The first use of a dedicated machine made for HD vegetation cutting was in 1995/6 in Cambodia when the HALO Trust used a Russian tractor with a "hedge-cutter" on a boom arm. One side of the tractor was armoured and the machine cut a swathe alongside a safe area. The cutting head was supported on "sacrificial" wooden skids and when I met them, the skids had not yet needed to be replaced. The cutter had knocked the fuzes from fragmentation mines and the skids had not detonated surface pressure mines. The disadvantage of the tractor was that the deminers could not work in a conventional manner by cutting well-spaced lanes out from the safe lane. None-the-less, the machine could deploy itself over bad roads and was the first of several low-cost versions. It was well used.

The second known use of a dedicated machine involved the NGO MgM in Angola who mounted a "brush-cutter" on a boom arm attached to an MPV.

Using off-the-shelf parts and a recovered MPV (from the days of South Africa's involvement in the conflict), the idea was sound.

Even so, it has the same limitation as the HALO tractor because it can only clear a swathe in front of the deminers although that swathe is deeper. The MPVs used by this group have conventional tyres and wheels, so cannot be driven over a suspect area even when only small antipersonnel blast mines are anticipated. The cost of one of these vehicles new means that they have not been sold as vegetation clearers to any commercial companies - which implies that they are not commercially cost-effective.

The above is a DOK-ING rotary cutter that has been widely used in the Balkans. Several other variants are commercially available, many with optional other implements on the hydraulic arm.

The PRO MAC BDM48, for example, is also used to engage the ground.


Flailing undergrowth

Flails that were designed to engage the ground and try to detonate mines can sometimes be used without striking the ground - and can make effective vegetation cutters. However, their very high cost does not make them attractive. The largest commercial demining group in Africa found it cheaper to make its own flail than to import one from elsewhere.

Their "improvised" flail has been used throughout Africa and the Balkans.

Remotely-controlled and mine protected mini-flails have become popular because they are cheaper to buy and run, and can be more versatile in the field. Although usually designed to strike the ground and detonate pressure devices, their inability to do this thoroughly has led to many groups using them primarily in a vegetation clearance role.

A few cannot survive detonating a large AP blast mine. This negates the advantage of remote control because if the machine cannot enter a suspect area, it may as well be manually controlled.

This is one such machine, and despite having been "hyped" around the world, it has not sold to commercial groups - perhaps because the price tag approaches a quarter of a million dollars, but mainly because it cannot enter a suspect area with confidence that it can return after running over a small blast mine.


This is the first mini-flail - which was developed for the US military - with a well known face posing for scale.

Here is the same machine. This flail is very small, but its Milspec meant that it was underpowered and had very limited utility. Unfortunately, its full potential was not realised via a process of sensible refinement. Behind it you can see the CECOM NVESD mini-deminer, which is little more than a platform for developing remote controls. Its design is impractical and unreliable. Given that there was never a stated need for such an expensive toy, it is no surprise that they do not sell to commercial demining groups. Their flail could have been different, but they missed an opportunity and it was not taken seriously enough by US bureaucrats.

Instead the US decided to support a UK built mini-flail first known as the "Beaver" but then renamed the "Tempest". It had already been funded by UK charities and the British government, then got a further injection of support from the US taxpayer.

Here is a Tempest I encountered in Bosnia in 1999. with a narrow wheelbase and heavy armour, it was prone to falling over on anything but flat ground. It also did not have the power to work on any incline. The "after-thought" armouring on the sides made the engine hard to cool - and one overheated so badly that it caught fire and burned-out in Bosnia.

Without addressing the fundamental problems with the design, the developers fitted fire-extinguishers and an alarm that sounded when it overheated.

Here is a Tempest I encountered in Mozambique in 2002. In the Autumn and in a relatively cool area of flat pasture, it could only work for a few hours in the morning - and even then the overheating alarm went off regularly. Too heavy and with fundamental design errors, it was limited to cutting grass beside roads. This is probably why commercial groups are reluctant to invest the $90 - 150k needed to own one, with the cost of a low-loader with crane to transport it. Those I have seen working have been "donated" be those who funded the development - keen to make themselves look effective. A few NGOs have "bought" them - and the very latest version is reported to have overcome some of the serious problems in earlier models. I have not seen this for myself.

Better attempts were made in the USA and in Switzerland with the Hurricane (not for sale) and the Digger D1 or Digger D-2 (pictured in Sudan)

The Bozena (below) made a "name" for itself - (its use to strike the ground before manual clearance in Lebanon was cited as the cause of several accidents when damaged mines became more sensitive) - while other manufacturers adopted their name from others....

The "Diana"....


The most successful mini-flail range to date did not get any government support for its development. It is the Dok-Ing flails made in Croatia.

Various models have sold to several commercial, NGO and military groups. When used just for cutting the undergrowth, it can save considerable time and remove any tripwire threat. Further, its use against the shallow AP mine threat in Croatia is claimed to have been very effective. The MV-4 model shown above is reported to have been the most successful. Unfortunately the manufacturers "oversell" its performance on their website - and present it as a "clearance" tool. It is in fact an area-preparation tool. See the SOPS for its use.

The MV-4 at work in Sri Lanka, where it can tackle heavy undergrowth as well as make breaches through the AP mine belts.

Tree cutting

The need to cut trees was identified - and various approaches tried. In fact, it is rarely necessary or desirable to cut mature trees which always have some value to the local population (for wood if not for fruit-crops).

The "Tree-shear" developed for forestry was adapted by Hydrema for a demining NGO with R&D money.

The picture above was taken while it was being demonstrated for me. In fact, it was little used because its use added another action to the demining task with little benefit, and (once again) it could not drive onto an uncleared area. Even with a long reach, its utility was very limited and I know of no demining groups that have purchased one commercially.

This huge Hitachi machine was billed as being capable of chewing through the biggest trees - and also having a blast-proof cutting head. When it was donated to Afghanistan, it was soon broken and it was found that it had been constructed using materials that could not be readily repaired in-country. The cutting head canot survive an AT blast without severe damage, of course.

Similar machines have been donated to Cambodia.....

Where the mess they leave after cutting can make their use more trouble than its worth.

High purchase and maintenance cost, coupled with their size limiting access, has made these machines not cost-effective for purchase, although they may be attractive for occasional hire.


Clearing rubble

Around damaged buildings, mines and ordnance may be buried deeply in collapsed rubble. The Afghans were the first to deploy armoured back-hoe machines to lift and spread the rubble for manual deminers to go through.

Also useful for clearing ditches and irrigation canals, the system has the advantage of using a commercially available machine that is usually well supported for spares and not loaded with huge development costs.

Armoured back-hoes have been used in many countries, and most recently (2005) by SARVATRA and NPA in Sri Lanka with a vegetation ripper and rake attachment to prepare the ground for manual deminers.

Using converted plant machinery, costs have been kept to below US$25k, which makes these machines look very attractive.

One other way to cut undergrowth and keep costs low is to use hand-held machines. These can only be safely deployed where there is confidence that tripwires and protruding fuzes present no threat - but this is increasingly the case as mined areas age, tripwires disintegrate and fuzes atrophy.

This petrol driven "Weed-whacker" is being used in Cambodia.

This similar cutter is used by SARVATRA in Sri Lanka. The reach is limited, but low-cost and ease of use can give it significant advantages.

Carrying detector arrays

Machines have been used to carry detector arrays for some time - with their success largely being limited to working on roads and looking for large targets (metal-cased AT mines). The advantage of using a machine is covering a wide area quickly, but the speed makes the detection and pinpointing of small items impractical. On roads, the normal debris of human passage means that there is often a lot of small metal anyway, and in some cases it is decided that this can be safely ignored.

The first machine developed to carry mine-detector pans along roads was the Rhodesian Pookie. Used within days of the mines being laid, and driven by people who often spotted the ground disturbance visually before passing over it, the Pookie had considerable success. Its limitations were an inability to find plastic-cased mines that had been concealed for any time, an inability to locate anti-personnel mines, and some difficulty negotiating inclines in wet conditions.

The KIMS system using a large Ebinger array on the front of an MPV is a modern replacement. With sophisticated GPS recording systems, large areas can be scanned far more quickly than by hand. Of course, the reliability is limited to the skill of the operator, and all signals still have to be investigated by manual deminers.

This system has now been modified and renamed the WADS and was scheduled for use in Angola during road clearance during 2005 (it was never properly deployed).

Some machines are developed specifically to carry other detector heads, or adapted for the purpose.

This ARTS machine is meant to carry a range of attachments, including a broad detector array (I do not know of any real deployment of this machine).

This "Chubby" copies the Pookie layout and carries the detector pans between the wheel-sets. What it has in common with many other detector carriers is that the base vehicle is an MPV - raising the question of why it should need to be protected against mine-blast if it can genuinely detect mines in real time? And if it cannot detect them until after it has passed them, perhaps some thought should be given to using wheels that would not be disabled by the smallest AP mine blast?

The answer in some cases is that the machine needs to be an MPV because it must pass over the mines before detecting them - like this CASSPIR that is used to drag a VAMIIDS detection system. The CASSPIR can have steel wheels or solid tyres fitted before it starts work (phenumatic tyres are just used for transit on roads), but most carriers do not have an option of AP mine proof wheels or tracks.

Carrying water

Hard ground slows deminers down, and there is some evidence that it can make accidental initiations more likely, so it is fairly common to use water to soften the work area. Sometimes the water is pumped around the site from perimeter tanks using long hoses and expensive pumps given by donors. Usually it is taken to the site in a tanker and carried to the lanes by hand because the tanker is too big to drive along the safe-lanes that give access to a work area.

This low-tech solution has a steel tank and pump that can load and dispense water efficiently. Its footprint is considerably narrower than a two metre wide safe lane, so it can get around the worksite without risk. Surprisingly, it even has a reverse gear. Made in Sri Lanka in 2005 by SARVATRA (supported by NPA), it's price using new off-the-shelf parts was less than US$3.5k.


You may have noticed that the great success stories in mechanical assistance have been achieved without outside finance. The best MPVs are developed from combat vehicles already in existence (pioneered in Southern Africa). The best mini-flail was developed to meet a local need before looking for an international market - and its tracks are capable of withstanding AP blast mine detonations (from those mines found in Croatia), allowing it to cut undergrowth over a wide area in front of the deminers. The cheapest ground preparation tool was made by SARVATRA (an Indian NGO) using converted plant machinery in Sri Lanka. In general, research and development efforts that receive government funding tend to be obliged to stay on a fixed development path even when it later becomes obvious that the path leads in the wrong direction. Some of the machines featured above have been sent to demining groups around the world - but at the donor's expense. Very few approach commercial viability. Often they are entirely ill conceived but sometimes they are just too big. The only time that large machines can really achieve cost-effectiveness is when they are pooled within one company and hired out as a resource to a number of demining groups active in the same region - and even then, a large size and weight can really inhibit access to sites.

Despite many calls over the years for a genuinely small vegetation-clearance machine (a "bush-whacker" on steroids), all of the so called "small" machines that are currently available weigh more than 3000 kg - and the current market price for them starts at around $90k. They are too heavy and too expensive, especially when the cost of their transporters are added to the original cost. Poor design often also means that running and maintenance costs are prohibitively high.

What is needed is a radio-controlled "micro" machine - capable of being transported in the load-bay of a pickup truck so that no new transporters have to be bought. The machine should be low-cost, able to survive AP mine detonations (which can be achieved by venting and informed materials selection rather than by adding much armour-plate) and must be field serviceable.

One such machine has been waiting for funding support for several years (the prototype "proof of concept" looks very promising), but small machines with small aspirations do not seem to appeal to the R&D donors.

The "Locust" awaiting some capital investment in Florida, USA. (The top armour has been removed along with the "Hess-pylon" [Roger Hess concept] vegetation cutters.) Yes, I was involved in the design - and I would dearly like to see it finished and tested.