Winds of Destruction: The Autobiography of a Rhodesian Combat Pilot
Page 67
Having lost all of their ‘air ambush’ equipment during their very first day in the country, the CTs must have lost confidence in the system because I cannot recall another incident of this type inside Rhodesia. Occasionally they were employed in Mozambique. Long before this incident, I had read of an antiaircraft system, which Mao Tse Tung developed and named ‘ground cannon’. Later I will discuss my own tests of this crazy, crude and effective system.
Down in the southeast, on 27 August, a Grey’s Scouts callsign on horseback was following tracks of a large group heading straight for the Mozambican border. Tol Janeke called upon the Chiredzi Fireforce to join up with his Repulse Fireforce and placed the joint force close to the area of anticipated action.
Tol amalgamated forces whenever he judged it necessary, which is why in my opinion he was a particularly successful field commander. Every officer had been taught the ‘Ten Principles of War’; one of which is the all-important need for concentration of forces. Few heeded this in the great spread of activities where too few aircraft were called upon to meet too many needs. Tol not only practised this principle, he ensured that the concentrated force was correctly placed for immediate use.
In this particular case, two K-Cars, six G-Cars and two Lynx moved to c/s 24B, who reported that he was two hours behind the CTs. Flight Lieutenant Ginger Baldwin, flying lead K-Car, was surprised by the speed at which c/s 24B was covering ground on horseback. He knew the Fireforce troops could not possibly keep up with them and, since there was no fuel close at hand, decided to land the helicopters and await developments. The two Lynx loitered over the helicopters and maintained communications with 24B.
The horses were watered at a pan where c/s 24B reported twenty-nine CTs had been at water’s edge about one hour earlier. Noting how far this pan was from a game fence that lay beyond, Ginger decided to deploy two stop groups to the fence on the line of movement. This had only just been done when 24B called contact. The Fireforce was over the CTs shortly afterwards and learned that one of 24B’s men had been killed during the engagement.
Ginger described the ground over which most of the aircraft took on groups of bomb-shelling CTs as “... so flat and vegetation so uniform that it was impossible to pinpoint a specific point.”
Tol’s comments on the ASR were:
(1) The FAF 9 Lynx, K-Car and G-cars were positioned with the FAF 7 Fireforce when the follow-up started. This resulted in a combined effort of 2 Lynx, 2 K-Cars and 6 G-Cars being brought to bear when contact was made.
(2) The final count was 40 killed and 13 wounded captured, 8 with weapons. Intelligence has confirmed that 10 ters were escorting 97 recruits to Mozambique for a week of training before returning to Rhodesia with weapons. This contact will no doubt discourage recruits from willingly joining the ters.
(3) It would have been almost impossible to tell who was a terrorist and who a recruit once contact had been made, particularly as the MIU rifleman was killed in the initial engagement.
From our point of view, any man who would be returning to the country trained and armed within a few days, was a CT already.
Chapter
8
Project Alpha
FOR MANY YEARS I HAD questioned the effectiveness of conventional bombs and rockets. Earliest doubts about the efficiency of cylindrical-shaped bombs and warheads were confirmed when I studied their effects at the conclusion of the big Air Force Weapons Display at Kutanga Range twelve years earlier, back in 1964.
Senior officers had laughed off these concerns because they had used the weapons during WWII and had nothing but praise for their efficiency. In fact one very senior WWII officer asked, “What gives a young puppy like you the right to question proven weapons?”
Whilst agreeing that they were well suited to many of the situations for which they had been designed, I was unable to convince my seniors that these same weapons were totally unsuited to counter-insurgency bush warfare. During my FAC work with jets, I watched many strikes but these only reinforced my lack of faith in both imported and homemade bombs.
For over eighteen months Canberras had been limited to using 250-pound, 500-pound and 1,000-pound bombs, none of which was effective and they all involved unacceptably high expenditure of valuable foreign currency. Everything pointed to a need for a drastic change to provide Canberras a safe and effective anti-personnel strike capability.
Although work had continued in an ongoing effort to sort out the 28-pound fragmentation bomb problem that led to the destruction of a Canberra, this weapon system could only be employed with any degree of accuracy inside the Strela missile and anti-aircraft gun envelopes. This in itself was unacceptable, but the thin line of widely spread, puny detonations running through any target was also unacceptable. What we needed was an anti-personnel weapons system that would give a Canberra clout to match its load carrying potential. For safety reasons alone, such a system had to allow Canberras to fly over the most hostile of targets below 500 feet at speeds exceeding 280 knots. If this attack profile could be achieved, it would render Strela harmless and would also substantially reduce threats from manually operated guns.
I was certain we needed a system based on large numbers of small bomblets that could be induced to spread laterally in a wide carpet over an effective strike length of at least 800 metres. Each bomblet would have to retard very rapidly to be well behind the aircraft at the moment of detonation. And, of paramount importance, each detonation had to occur above ground to ensure that shrapnel reached an enemy hiding in ground recesses and trenches.
Having read about the USAAF’s use of solid steel ball bearings to flatten sizeable sections of jungle in Vietnam, I became interested in the idea of producing spherical bomblets. High-speed, low-level deliveries of enormous quantities of three-inch steel balls released from Phantom jets had been used to clear thick jungle vegetation. What really caught my eye in the USAAF article was the fact that balls spread themselves laterally during their short flight to ground.
One foundry in Salisbury and another in Bulawayo produced thousands of round balls for me. Because I was in a hurry and needed to keep costs down, the lead balls they manufactured were crudely made. The bag and string system I employed to release clusters of two-inch and three-inch lead balls from a Canberra, flying at 300 knots at 500 feet, was just as crude. No wonder the Canberra crews were not at all impressed with ‘PB playing high-speed marbles’ but I needed, and got, answers from the drop tests. Firstly, it was clear that turbulence from leading balls forced those following in their wake to move sideways. Instead of striking ground in a straight thin line, a random scattering of both two-inch and three-inch lead balls occurred along the attack-line; some as far as forty metres either side of centre. Secondly, the balls left long grooves in the Kutanga Range sandveld but every one of them lifted back into flight and thirdly, the balls retained lethal velocity way beyond first contact with ground.
Squadron Leader Ken Gibson.
I was encouraged by these results and was considering where to go from there when providence took a hand. Senior Staff Officer Air Armaments, Squadron Leader Ron Dyer, was my right-hand man in all air weapons projects. Immediately after our crude tests he brought his predecessor, retired Squadron Leader Ken Gibson, to see me in my office Ken was then working for the engineering firm that manufactured our locally designed bombs and Frantans. Because he knew something of what Ron Dyer and I were doing, Ken had come to Air HQ to give us wonderful news.
An engineer who had recently joined the company was studying the 28-pound fragmentation bomb problems with the managing director of the company who had designed the system in the first place. The specific problem they were studying concerned safety of nose fuses which, though designed to activate bombs just above ground level, had been responsible for the premature detonation that killed two officers and destroyed a Canberra.
Ken told us that when the new engineer learned of the importance of airburst, he said it might be easier and safer to produce round bo
mbs that would find ground level for themselves. The ground impact would initiate a delay fuse as the bomb bounced back into flight to detonation at a chosen height, just as we had been considering. Ken Gibson could not have brought better news and I set off immediately with Ron to visit the company.
For convenience the managing director of the company, whom I had know for some years, will be referred to as Denzil and the man with the new ideas, Bev. We were introduced to Bev whom I took to immediately. We had a long discussion during which he said the bouncing-bomb idea was no more than that—just an idea. I told him why I favoured this approach and why I had been testing spheres to facilitate low, safe and accurate delivery with maximum lateral distribution. Since Bev had no experience with bombs or bombing and did not know any of the inherent dangers involved, he needed to learn about the operational requirements for the Canberra, as I saw them. I told him of my experiences and the reasons I wanted to move away from conventional bombs.
Explanation was given as to why cylindrical bombs suffered too many weaknesses in bush warfare situations. The primary weakness of cylindrical bombs and warheads is that, when they burst, shrapnel is driven out at ninety degrees to their longitudinal axis. To be wholly efficient against enemy personnel, a cylindrical bomb needs to be about six feet above ground and vertically oriented at the moment of detonation, but even when dropping bombs from very high levels the vertical attitude cannot be achieved and accuracy is poor.
If the same detonation occurs when the bomb is horizontal, it is at its least efficient angle because only a narrow band of shrapnel strikes ground at ninety degrees to the bomb’s longitudinal axis. The remaining 95% of the ground around the bomb is unaffected; yet paradoxically this is the situation that occurs when bombs are dropped at low level to ensure high accuracy.
Being streamlined, bombs descend directly under the delivering aircraft until they have fallen some 2,000 feet clear. Thereafter drag and the progressive nose-down pitch cause bombs to slowly trail behind the bomber. But a safe separation height can never be less than 2,000 feet to avoid damage, and even destruction, from large weapons detonating directly below the delivering aircraft.
This photograph shows a total of seventeen 500-pound bombs dropped by three Canberras. Note the huge gaps of ‘safe ground’ between the strikes.
In our case this meant that, for accuracy to be assured, the Canberras would have to pass over target in perfect range of missiles and guns. The alternative was to bomb from great height and accept both loss of accuracy and the fact that cloud could limit windows of opportunity for strikes. Neither of these situations was acceptable. Another unacceptable issue, no matter the bombing height, was that large gaps in a string of bombs left too much ground uncovered.
An inherent problem with conventional bomb design is the need for tail cones and stabiliser fins that are costly and occupy potentially useful space in a bomb bay. Spherical bombs are quite different. They do not poses wasteful appendages, nor do they suffer orientation problems. A spherical bomb bursting above ground will consistently deliver shrapnel through 360 degrees in all directions but always lose half into the air.
Delivered in clusters, spherical bomblets moving through air at high speed create high-turbulence wakes that induces lateral movement to following bomblets. Moreover, high drag on every bomblet causes rapid deceleration from the moment of release. Another important advantage is the natural tendency of round bombs striking the ground at shallow angles to skip back into flight, making airburst possible. Admiral Nelson used this principle to good effect against enemy ships by skipping round cannon shell off water to improve the chance of gaining waterline damage.
Having understood these explanations, Denzil and Bev were eager to assist us develop a spherical cluster-bomb system for Canberras because it was agreed that such a system was within the technical competence and capacity of the company. Denzil kindly undertook the initial research work at his company’s expense and I opened a project file marked ‘Project Alpha’. Projects that followed were Projects Bravo, Charlie, Delta, etc.
Bev considered it necessary to use a central spherical bombcore fashioned from 8mm steel plate to house the explosive charge and a multi-directional delay-fuse. This fuse would initiate a pyrotechnic delaytrain and without regard to the orientation of a bomblet when it struck ground. The central core was to be encased within a larger 3mm steel sphere with many super-rubber balls tightly packed between the inner and outer casing.
The purpose of super-rubber balls was to allow the inner core to compress them on impact with ground, thereby creating a latent energy source that would enhance a round bomblet’s natural tendency to bounce into flight. At the time we did not see that the rubber interface would be giving bomblets vitally important secondary characteristics. One was an inherent ability to absorb sharp shock loads on the fuse if a bomblet was inadvertently dropped onto concrete during handling and loading.
A variety of tests were conducted to prove prototype bomblets’ ability to recover off ground even when dropped vertically from a helicopter at great height. When we were certain we had a worthwhile project on our hands, I went to the Air Force Commander’s office late one afternoon with an eight-inch bomblet in my hands.
Having explained the design, I held the ball at waist height and asked Air Marshal McLaren to watch how the bomb recovered into the air after impacting the ground, whereupon I released the ball onto his office carpet. His reaction to the metallic clang was not what I expected and I do not think he even noticed the bounce. “Get that confounded object out of this office. You have six weeks in which to produce your system for full load strikes by four Canberras.” I was astounded by such a quick decision and said, “Sir, there is no money budgeted to meet your instruction!”
Mick McLaren was known for his ability to come to quick decisions. His reply was typical. “You concern yourself with technical matters and I will take care of the money. I am counting on you for success. You have six weeks to do the job, so get cracking!”
Schematic diagram of the Alpha bomb.
Air Marshal McLaren was the first Air Force Commander not to have serviced in WWll, so he had a flexible attitude towards weapons in general. He had studied every ASR and had called for detailed post-operational studies of Canberra bombing effects following a number of strikes in a variety of bush conditions. I was not involved in any of these studies but had read every report. None that he received gave the Commander any reason to be satisfied with cylindrical bomb efficiency. Without him actually admitting it, he agreed with what I had been saying for many months and obviously liked the spherical bomblet concept as the means by which to make his Canberra fleet effective. I suspect that Group Captain Norman Walsh may have had a hand in influencing the Commander’s opinion on the need for a cluster-bomb system.
I made a telephone call to Denzil and told him we had ‘green light’ on the Alpha Project and that Ron and I would be around to see him immediately. Denzil and Bev were waiting for us in the company boardroom together with the company’s accountant and a third engineer. Our excitement was somewhat tempered by the realisation that a project of this nature, if undertaken in the USA, would require many millions of dollars, involve many engineers and would take no less than five years to complete.
With only six weeks to finalise research and development and produce four complete carriage and release systems along with hundreds of bomblets, it was obvious we had to make final but correct decisions right away. Denzil did some preliminary calculations that made it clear that cutting of metal had to start next day. In turn this meant we had to finalise the specific dimensions of both inner and outer casings at this very meeting so that preparation for half-sphere presses could be initiated that night.
Canberra bomb-bay drawings were spread out on the boardroom table to confirm preliminary designs generated during our earlier work. I had to specify the number of bomblets in a single load so that Denzil and Bev could calculate final bomblet dimensions. For convenience
we had already started referring to the bomblets as Alpha bombs (Project Alpha) and I gave the operational requirement as 400 Alpha bombs to be released from eight independent containers, which we named ‘hoppers’.
The engineers quickly sketched profiles of four units comprising two hoppers each to establish the internal volume of each hopper. Having done this, they established that the external diameter of each Alpha bomb would be 155mm. From this the size of the rubber balls and inner bomb core were also determined.
The very next day preparations were in hand to press the metal blanks into half spheres. By Day Three the welding of half-spheres for inner cores and outer casings was already under way. The first hundred outer casings were taken off-line and filled with concrete for initial proving trials.
At New Sarum Warrant Officer John Cubbitt had his Drawing Office staff busy finalising the hoppers design and within two days Station Workshops were fabricating prototypes for preliminary drop trials of the concrete-flled Alpha bomblets. The concrete units approximated very closely to the calculated final weight of explosive ones.
At my insistence flight trials commenced with the fitment of a camera into a Canberra bomb bay to record the release characteristics of the old 28-pound bombs from the ‘bomb box’ unit. The bombs we used were practice units that had the same shape and ballistic characteristics as live ones. Two full-load tests of ninety-six bombs each were made. In addition to the bomb-bay camera, each drop trial was filmed from a formating Vampire.