CHAPTER 15 HALO BOX OR BLOWING UP BRIDGES AND THINGS BUGS BUNNY STYLE

A post script to last week's chapter: A trusty correspondent, (John Peirson)  informs me that, Robert Warren-Codrington was also known as "The Hitch-Hiker."  Apparently the name Fingers was already taken, and Bob still had his hiking thumb! I have to say Bob was an extremely tough and hardy man - he became so adept at managing his remaining digits, that he could still handle his weapon, and eventually nagged me into allowing him to parachute again. Keep the extra info coming people, I enjoy hearing from you, and will add your anecdotes as I receive them.

In the old Bugs Bunny cartoons, Willey Coyote always tried to blow things up, misjudged the fuse time, and ended up on the wrong side of the explosion.

The PTS was responsible for dropping, not only humans, but also supplies and, in order to do so, we also played around with fuses and explosives. Luckily, we never blew ourselves up.

The SAS parachute deployments into the Tete province of Mozambique had a dramatic and deadly impact on the routes taken by opposition groups into the North Eastern part of Rhodesia. The concept of dropping a Pathfinder team to look for a DZ to take a static line follow-up drop worked well, and the roads and paths leading to the Rhodesian border became very dangerous for the enemy to traverse. The number of incidents in the North Eastern border area reduced dramatically. And so too did the number of operational parachute drops.

But at the PTS we still carried out continuation training with the SAS, and it became evident we would have to find a way of dropping much heavier HALO loads; supplies of explosives and their bits and pieces, landmines, fuel, canned water, extra rations. Basically, things which were too heavy, or too scary for the troops to cart down with them.

The staff of the Parachute Training School who helped to develop the Free Fall or HALO box L to R Sgt Kevin Milligan,Sgt Iain Bowen, Sqn.Ldr. Derek de Kock (The Boss.) Sgt Mike Wiltshire, Sgt Ralph (The Rat) Moore, Flt/Sgt John Boynton School Warrant Officer, Flt/Sgt Dennis (Charlie) Buchan, Flt/Lt Frank Hales Training Officer/ Chief Instructor. Lower Down Sgt Bar Bear Mascot. These PJI's became the senior staff of a much larger Parachute Training School a short time later when it was decided to parachute train almost the entire Regular Rhodesian Army. All the members of staff shown here with the exception of Derek de Kock and Mike Wiltshire were ex Army and Mike had joined after being a London Bus Driver. 

We opted to stick with the well-tested KISS method. Keep It Simple, Stupid. We had six problems to solve:

1.  Get a box or suitable container we’d use in the future.

2. Decide what we could put into it.

3. Decide how much it should weigh, remembering it had to be easily moved into the open door of the Dakota by two PJI dispatchers.

4.Pick a parachute  that could take the boxes and handle the strain of a terminal velocity opening shock.

5.Finally, get hold of an automatic opening device which we could throw away after use as, deep in hostile territory, we would be lucky to get any of our equipment back.

 6. It should cost next to nothing.

 Major Tom Gentleman of # 3 Air Supply platoon helped in providing an air supply box and harness, as well as the necessary information about its weight limits.  #.3 Air Supply Platoon thought 350lbs(160kg) was a useful weight, and could be tipped out of the Dakota parachute door without too much trouble, provided one did not have to shove it around inside the cabin too much. Most importantly, these boxes cost next to nothing, and Air Supply had stacks of them.

They were approximately 1200mm high and 800mm square when opened out and could even be fitted with a crush pad on the bottom, if they needed to carry delicate stuff. The harness wrapped around the box was made of flax webbing with a breaking strain in excess of 1000kgs, and it had suitable steel D rings for attaching the parachute.

Four problems solved -  by simply talking to #3 Air Supply platoon. The next issue was to get hold of a suitable parachute. There were a reasonable number of 24-foot diameter reserve parachutes which had reached their use-by dates, and there were also a large number of emergency aircrew parachutes past expiry. All these parachutes were of the 24-foot diameter flat canopy type and were supposedly capable of withstanding terminal openings with  loads in excess of 450lb(205kg).The parachutes used by No.3 Air Supply Platoon were mainly of a supply dropping type; always deployed with a static line, and always in the canopy-first mode.This method was used so the aircraft could do supply drops from a very low altitude and reduce the opening shock factor, but at terminal velocity they had to be strong because the opening shock was high.

Unfortunately, we no longer had the option of dropping supplies from low altitude.

Shortly before we started to develop the HALO box, it was discovered that the terrorist groups had obtained SAM 7, or Strela, hand-held anti-aircraft

missiles. These were heat-seeking devices and would probably go for aircraft engines. One thing was certain: the old Dakota could not outfly them. But the missiles did have an Achilles heel. They were unlikely to get above 12,000ft AGL. Thereafter, all HALO drops in hostile country would be from 15,000ft or higher if at all possible. All supplies would also be dropped from great heights if the aim was to remain clandestine.

So the issue remained. How could we get the parachute to open at the correct height. Having tipped it out of the Dakota at, say, 10,000 feet AGL, we might need it to deploy at 1500 feet AGL. We needed an automatic opening device – one that could be set to go off at 1500 feet AGL at any place we chose.

At this time we’d obtained various automatic opening devices, but none of them had the capability of  being set to go off at different altitudes. They were meant for the civilian sky divers, who would usually land on the airfield they took off from. The only other automatic opening devices were fitted to ejection seats, and those would not be made available to people silly enough to jump from a serviceable aircraft.

In the PTS, if there was a problem it could usually be solved in the crew room. All the PJIs were encouraged to come up with outlandish ideas – nothing was too outrageous to mention. Flt Lt Frank Hales happened to be in this room, idly listening as someone expounded a plan to use a timer and an explosive charge to blow the parachute open, when a different idea struck. In the school, we had available to us a reasonable quantity of explosives, cortex, safety fuse, detonators and – most importantly – electric fuse igniters. Frank grabbed a reserve parachute and sent one of the UT/PJIs down to Safety Equipment Section to get a few yards of 50lb and 150lb breaking strain ties, used for packing static line parachutes, and a big needle from the parachute repair shop.

He slowly pulled the ripcord out of the reserve. Normally when this was done, the elastic bands on the reserve would pull the cover open and expose the spring loaded pilot chute, which would pull the 24-foot canopy out. This time, however, he undid the elastic opening bands and, keeping the cover in position, replaced the ripcord with a piece of 50lb nylon string. Then, using the needle, he poked a hole through a short piece of safety fuse and threaded the string through that as well. He tied the string up and, bingo – there was a parachute held closed by a piece of string which would hopefully be severed when the safety fuse burned through it. The opening elastic bands were reconnected and all was ready for the first trial. As soon as the fuse burned through the 50lb thread the parachute burst open perfectly, and there was  no doubt  we had solved the problem, a bit like a Bugs Bunny cartoon, but it worked.

The next step with the HALO box was to find out how long it would take to plummet  to 1500 feet, test the burn rate on a piece of safety fuse, cut it to the correct length, fit it to a parachute, and drop the box.

The PJIs were sent off in various directions to get boxes, parachutes, and stuff to fill the boxes to the required weight. I went to OC flying to keep him in the picture, and to request the loan of a helicopter from No.7 Sqn for a couple of hours. The idea was to take a truckload of about eight boxes out to one of our favourite testing spots in the nearby Seki tribal area, a sparsely populated place with a large, flat, and almost treeless area.

The Alouette III chopper was one of the few helicopters which could climb to 10,000 feet ASL with a load of 350lbs and a man to toss it over the side. As soon as it was pushed out, the pilot would tell us over the radio, I would start the stop watch, and when the first box hit the ground, stop it. By comparing that time with the burn time on a piece of fuse, we could calculate the time for the parachute to open seven seconds before it hit the ground.

Very scientific and near fool proof.  Or so we thought. Like all clever chaps who play with fuses, we used a back-up – there were two fuses piercing the string holding the parachute closed, and two electric fuse igniters.

The box was loaded onto the chopper which climbed to execute what we thought would be a perfect HALO drop. The chopper flew in and I started the stop watch. But the box slammed into the ground sans parachute. Back to the drawing board.

The safety fuse was re-tested and found to be satisfactory. Safety fuse does not need a source of oxygen to burn, as it generates its own supply chemically, and is even capable of burning underwater. What could be the problem?

It eventually dawned on us that when we flew higher there was less air pressure, and therefore the fuse would burn slower. The box had taken 30 seconds to fall the 5000 feet from its drop height. We had cut the fuse to burn for 23 seconds, yet it still hit the ground. We cut the fuse to 18 seconds and repeated the drop. This time it worked. The parachute deployed at about 1000 feet AGL and landed softly. The idea was good, it worked, and it cost next to nothing.

The next phase of this experiment was to throw the box out of a Dakota flying at an operational height, and have the PJIs follow it down. This would help calculate the correct fuse burn time to use on operations. After that, we could invite the SAS to come out and play with us, and seek their advice on any modifications.

On the first jump I followed the box. It tumbled and slid all over the place, and it was necessary to track away from it for a good distance. It did however remain below me for the entire time. The last thing we wanted was to overtake the box on the way down, and find ourselves directly under a 350lb missile. Or, for that matter, to be directly above it and have its parachute deploy early. Neither was conducive to a long life.

Being on the ground during these experiments was also dangerous, as we could not guarantee the dispatcher would be accurate. It was easy to miss the actual target by 1000 yards or so, and it often seemed as if the box was coming straight at you and you did not know whether to run, or dive under the truck.  Fortunately, the powers that be in Air Force Headquarters did not know what we were doing and left us alone as long as we did not do too much damage or kill anybody.

We had to stop the box wandering all over the place during the freefall phase of its drop and came up with a plan to have a pilot chute from a reserve parachute, which was spring loaded and easily folded and tied to the harness. When the box was pushed out of the aircraft, a static line would break the string and the pilot chute would deploy and hold the box steady. It also meant there was less chance of a parachute getting fouled by a tumbling box.

The fuse idea worked well, with only one restriction: the drop height needed to be 15,000 feet AGL. Always. Calculating the burn time of the fuse as it passed through different altitudes was too unreliable – and we wanted to keep well out of range of the Strela/SAM 7 missiles.

On one of the early operations using the HALO box, the SAS stick were not jumping in to look for a follow-up DZ, but rather to do something nasty to a bridge in the Tete area of Mozambique. This drop was to take place towards last light. We were told to drop the box, “As close as possible; on the bridge if you can get it. We don’t want to carry that stuff too far.” The box was packed with various types of explosives, tinned water, and other useful items, to a weight of 350lbs by the No.3 Air supply platoon.

I rigged the parachute, carefully tested the safety fuse for burn time, and fitted the electric fuse igniters. The two pilots were briefed in the usual fashion, shown the initial target points and told we needed to be at 15,000 feet AGL over the target - a narrow concrete structure spanning the river.

Before take-off we’d done the usual preparations; obtained the best possible Met forecast for the drop, and selected the exact point for the dispatch. As we drew closer I could see the spot and called the troops down to the door to point it out to them. We pushed the highly explosive box into the door and hooked up the static line for the pilot chute. After a few final instructions, the pilots flew over the exact point, I lit the fuses with a six-volt lantern battery, and Mike Wiltshire and I shoved the box out, which was immediately followed by the stick.

We carried on in the same direction for about ten minutes, awaiting the call from the stick to tell us they were OK. The all-important call came soon enough. "Congratulations! The box landed on the bridge." I was extremely pleased with myself and the pilots, and entertained thoughts about turning the Dakota into a bomber.

But one should not jest about such things. We were eventually asked to throw bombs out of the back of the jolly old Dakota, as a diversionary tactic to draw attention away from parachute deployments.

A few days later, PTS was tasked to carry out another HALO box drop, a little further into the Tete province of Mozambique. This time we were told to drop the box close to a small outcrop of rocks in the middle of a large open space. The same Mazoe River junction was used as the IP again, and once more we ran in at 15,000

feet. The dispatch point was easily seen from our spot in the sky, and the drop was exactly as planned.

 For the second time in a row I managed to hit bullseye. The box parachute was draped over the biggest rock of the outcrop. I really thought I had this HALO box dropping business all wrapped up. A short-lived opinion. I was brought back to Earth with a jerk when I missed the next drop by nearly three nautical miles.

We made HALO box drops on at least sixteen different occasions using the fuse and string method without a single failure. We tried many automatic opening devices but they were either unsatisfactory or were unavailable because of sanctions.

 Eventually, we managed to obtain a Russian-designed automatic opener called the KAP 3. It was ideally suited to our needs   because it was robust, easy to set, difficult to break and could be set to work at any altitude regardless of take-off height. It was designed to operate the main parachute or any parachute with a ripcord and could be fitted to the HALO box with ease, thus giving us far greater flexibility with regards to drop heights. Add to this, we were able to get a large number, they worked 100 per cent of the time, and could easily be serviced and checked by the instrument section at New Sarum. These openers were copied by a South African manufacturer specifically for our needs.

Another item HALO dropped using both the fuse and the KAP3 methods was the 44 gallon fuel drums of Jet A1. These were used by the Alouette III helicopters of No.7 Sqn if they were on a recovery mission beyond their range. The big problem we found with these fuel drums was that the two ends would bulge and start to leak around the seam. Not an ideal situation if the chopper boys were relying on the fuel inside to get them home.

 The bulging effect on the drum was caused by the opening shock of the canopy-first deployment of the 24 foot parachute, combined with the hydraulic effect of the fuel inside the drum moving about. To overcome the hydraulic effect we filled the drums to the absolute brim and screwed the bung down tight to ensure there was no air space. We also had two pieces of 25mm thick plywood cut to fit inside the top and bottom rims, with a small space cut out for the bung at the top. These

two pieces of plywood were kept in position with steel strapping. A webbing harness was attached around the drum and a 24 foot parachute was fitted to the harness, complete with KAP 3. A.O.D.

When it was tipped out of the door it fell in a horizontal position, at very nearly the same rate as the human body. A small radio beacon could be fitted to the drum so it could be located in the wilderness. Before we fitted the plywood ends, a mist of fuel would emit from both ends after the parachute deployment blew the lids open. Later, I wondered if this could be a weapon of some kind, but never proceeded with that line of thought. Which is probably a very good thing - cartoonish experiments can go too far.