Miles Moffat of Christchurch has been perfecting the design and now has a website http://www.lan-cor.com/ for it featuring a short video. Marketed under the Lan-cor name (an abbreviation of land-anchor), it works on the screw principle. Leonardo da Vinci would be proud of it.

We ran some tests in a variety of terrain.

The first was in hard dry ground with embedded stones below the surface. The second in soft moist soil next to a bog, the third on a shingle beach and the last on a sandy one. The load was a laden Terrano sporting a 10,000 lb electric winch.

The Lan-cor anchor is sectional, there’s the main auger part (that looks like the tip of a huge PK screw) with a square driving shank then an extendable shaft that clips to it. The shaft can be lengthened as the anchor buries itself.

Spring clips similar to those used in extendable tent poles fitted inside the shaft sections make this easy, fast and secure.

A two-section pipe handle is inserted through loops at the top end to turn the shaft. Just above the auger a permanent sleeve is free to rotate on the shaft with a short piece of wire rope fitted to it via a thimble. A thimble is also fitted to the other end of the wire for attachment to a winch.

The whole Lan-cor anchor system fits to a neat strong carry bag with logo on the side and sturdy handles.

It weighs in at about 9 kg, which is light for a ground anchor, making it very suitable for small vehicles that may be compromised by heavy gear or have limited room. Most other ground anchors of the plate and pin or spade type are much heavier and take more room. Having the bag makes for clean and easy handling.

In operation the Lan-cor is assembled in short mode, spiked into the ground leaning away from the load and then screwed down until it stops. As it buries it takes the end of the wire down with it via the rotating collar.

Once the going gets tough the winch is attached and powered, gently at first. If the anchor moves then back the winch off and screw it further down as the soil will be loosened.

Repeat this until it holds, fitting the shaft extension if necessary. As winch load progresses the wire gets pulled down into the terrain to pull in a more direct line. The load on the anchor is taken sideways, not axially. This is its "secret".

Our first test was in hard ground with hidden rocks that impeded the anchor somewhat. It took three attempts to get it to set firmly.

The main reason for this appeared to be that a rock directly in the winch line and close to the anchor could prevent the cable cutting down into the soil for a straight line pull so would act as a fulcrum that converted a proportion of the load to a vertical load.

This would attempt to lift the anchor back up through its entry hole.

Once set, however, it held well and the Terrano was successfully winched up the bank.

The winch was working quite hard for this even with a double purchase so the anchor held a good load as the vehicle was nosed up a steep bank as if being hauled from a creek.

The bank was not smooth so the wheels had to also ride over lumps on the ascent. Grabbing a spade and cutting a narrow slot to help the cable cut downward helped. Let’s face it – how often do we need to set an anchor in hard ground?

In softer terrain this was not a problem as the wire could more easily follow the auger and then slice down as the load was applied. Even if the anchor moved on first application a few more turns of the handle took the anchor down far enough to hold.

The Terrano winched itself through a bog with one pair of wheels down to the chassis and pushing a fair chunk of mud with no movement from the anchor.

For our next test we moved from the hills and farmland to a shingle beach. There we backed the vehicle over the crest and down toward the waves, the sort of situation people get into quite regularly and one very difficult to recover from when alone.

One can often get off such a beach at low tide by building speed on the lower, harder area and using momentum to reach the crest. Without that momentum there’s no way of escaping the beach and tide except by winch or a tow (that may require more than one vehicle).

On the steepest part of the hill the Terrano was wheelspun down until quite stuck. The anchor was easily screwed into the shingle 20 or 30 metres down the landward side and allowed a single pull on the winch to haul the vehicle up and over the bank.

A similar result was achieved on our last, sandy beach, test.

Our test truck was nosed up a sandy rise, anchored at the rear to another truck and its wheels spun into the sand then the anchor truck removed.

The Lan-cor was installed into the backside of a sand ridge. It wound down quickly and easily to full depth with the handle extension fitted and it held like a rock. It hardly moved as the load went on, even with the Terrano’s brakes applied.

Miles pointed out they’d previously done a test in slightly coarser sand and the anchor recovered a pair of VX Landcruisers simultaneously. This is on video.

All recoveries were with the vehicle transmission in neutral. After each test the anchor was easily recovered though speed varied with the type of ground.

It was fastest to dig from the sand with a spade, it unscrewed OK from the shingle and the soft soil. It was a bit harder to remove from the dry hard clay as the wire rope was well buried and snagged on rocks.

It was not difficult though, just took a little digging and much waggling of the shaft. Possibly not fast enough for a winch challenge but fine for normal recoveries.

We did not get to test it in the hard-packed shingle and stones of Canterbury riverbeds, though it should be fine in the pea-gravel areas.

It seems to be a useful type of ground anchor. It’s not quite a cure-all as there will be some situations where it may not work, though some ingenuity could help there, such as burying a chunk of timber above the auger to spread the load.

Usual recovery techniques of digging and jacking to reduce loads will help in any situation.

I see the Lan-cor’s advantages as being versatile, compact, light and easy to use.

It is well made and finished in a high visibility yellow.

The Lan-cor anchor is at present only available through the website lan-cor.com at $360 incl gst, plus freight from Christchurch