The Borneo Treescape
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Whilst watching a programme on television recently about the Pinan tribesmen of Sarawak in what is now part of Malaysia, I wondered at the changes that have taken place since my enforced visits in 1962 and 1964 during the so called 'Confrontation' with Indonesia (1962-1966). Then it was mostly unbroken jungle in which our troops were engaged in warfare with Indonesian forces on an almost 1000-mile border from the state of Sabah in the northeast of the island through to the southwestern end of Sarawak that divides North Borneo with the State of Kalimantan belonging to Indonesia a great task for our limited strength of ground forces. A Victoria Cross (one of the eleven to be won since 1945) being awarded to Lance Corporal Rambahadur Limbu 2nd/10th Gurkha Rifles who retired recently as Captain Rambahadur Limbu, VC, MVO. |
Trees in Malaysia grow to a height of 200 feet ,the jungle canopy being very dense, and when flying over it at that time presented an unbroken carpet of verdant green. There was only two ways to travel the country, either by air to one of the few landing strips or by boat and hovercraft on one of the numerous rivers that also gave cover to the pirates that operated from them and for which even today the area is notorious. Pirate hunting in the South China Sea is another Far East Air Force story involving RAF Seletar's Marine Craft Unit and RAF Changi's Shackletons of 205 Squadron. That is another tale for another day.
The problem for aircrews having to bale out of stricken aircraft was that if they landed in the jungle canopy safely they dehydrated and died or disengaged their parachute harness and fell to their death 200 feet below on the jungle floor. Search and rescue could not be affected by helicopter because of the risk to the helicopter and crews. Downed crews could only be taken out from clearings that had been made to take patrols in and out of the area. The Parachute Regiments and RAF Regiment had an abseiling device to assist their decent from trees, etc. but it was far too large for aircrew use.
The then A.O.C. FEAF Air Commodore Greenham directed that the General Engineering Flight of 390 Maintenance Unit at RAF Seletar, Singapore, would design and develop a device small enough for aircrews to wear at all times hence allowing them safe descent to earth (to be known as a 'Treescape'). Squadron Leader Pricket of 390MU produced an initial design for development and manufacture by the technicians of the engineering workshops.
Newly promoted to Senior Technician when the project ground to a halt, I was detailed to take over the devices future development. The thinking, I believe, was that should the finger of responsibility be pointed because of the hither too slow progress, I was young enough to survive the rocket from on high making those more senior than myself 'Teflon-coated' as usual.
The design was good and operated on the capstan principle with the capstan being offset at an angle of 5 degrees between two light alloy plates. Using nylon cord it wrapped three times around the capstan and then ran between a scalloped plate and trapped by an eccentric cam (see diagram). When the trigger operating the cam was depressed overcoming the spring pressure it allowed the cord to pass between the cam and back plate lowering the crewman from the trees. Should the person using the device lose consciousness during use thereby releasing pressure on the handle their movement would cease until they recovered, so acted as a dead mans handle. A clip was provided at the lower end of the device to attach it to the Mae West lifejacket. The end of the rope protruding from the top of the Treescape was to be tied securely to the parachute harness before releasing one's self from the parachute then descending the 200-foot rope contained in a pack on the flying suit overall.
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On joining the project I
found the first finished prototype completed but almost inoperable except
for use by the heaviest of persons and then it jammed. On close examining
the device I discovered that one of the problems to my practical eye was
that the pivot hole in the cam was in the wrong position and was not releasing
the cam sufficiently from the scalloped back plate to allow the passage
of the cord freely. On paper the device should have worked perfectly. Corporal
Willie Wilson was the machining specialist working with me who also agreed
with my observations and so he provided a replacement cam incorporating
the suggested modifications.
We then set up a test to
prove it and it worked easily and smoothly.
For testing the now operable Treescape we put a giraffe ladder up to the workshop roof and tied the top end of the rope to the roof trusses with the other to a strop around the tester's chest. After Willie and myself had tried it we were followed by Squadron Leader Pricket and then the O.C., 390 M.U., Wing Commander Dainty, the four of us giving a good range of weights and heights as a test. The project was back on course. Other modifications were incorporated to reduce the overall size and eliminate any sharp edges and protrusions before passing it on to the School of Jungle Warfare for testing. The School was across the straights in the State of Jahore (they were very busy at the time, so I was assured, training the American Army and Marines the art of jungle fighting ready for Viet Nam, a fact that was never advertised).
The next step was to design the machining and welding jigs and fixtures ready for production. Meanwhile the blacksmiths produced the springs and the flying clothing section produced the packet to hold the cord with the device and decide the best place to fit it to the flying suit overall to avoid clashing with other equipment worn or carried. The cord diameter initially was in question, as we understood that knotting the cord could reduce the strength of it by as much as 50%. Sunlight's ultraviolet rays would also reduce the cord strength significantly and so tests were carried out in our laboratories to find the correct cord needed. We were correct in our assumption but the cord diameter used in the design was perfect for the task. After the go ahead from the trials we set up procedures for inspection, testing and the issuing of test certificates as we were allowed on 390 M.U. to manufacture and test lifting tackle, etc.
The workshops were soon in full production to supply all squadrons with our device starting, I think, with the Javelins of 64 Fighter Squadron. They were based at RAF Tengh although they were operating out of Pulau Labuan, an island just of the coast of North Borneo, where a certain Flight Lieutenant Larry Chamberline, now deceased, an old friend wore such a device as we manufactured. Fortunately for him but unfortunately for me he did not need to use it although we did lose aircraft, crews and passengers during the campaign for a number of reasons. A variety of aircraft were lost including the infamous Belvedere helicopters of 66 Squadron from Seletar.
Two problems developed; the first during testing when a spring broke and ripped my finger open from the knuckle to the tip like a 'Walls' pork sausage but a better grade of steel soon solved that problem. The second was a pilot who was too light in weight to operate the Treescape device being under 7 stones (I understand he was advised to eat more and drink less Tiger beer being as it is a good a laxative).
The Treescape, Larry told me, is still in use by our aviating personnel in the areas it was designed and made for by the technicians of 390 M.U,. RAF Seletar, Singapore, all those years ago although much modified of course. Many years later I was given an old copy of Air Clues containing a report of the project. Should anyone have a copy of that report I would love a photocopy of it as mine was lost or purloined in one of our frequent staff room moves that were common in the college in which I taught. George
Reeve
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