The Development of Air Power

By the end of the Second World War, the air was the key battleground of modern warfare; with control of the air, one could move small detachments of troops to deep behind enemy lines, gather valuable reconnaissance and, of course, bomb one’s enemies into submission/total annihilation. But the air was also the newest theatre of war, meaning that there was enormous potential for improvement in this field. With the destructive capabilities of air power, it quickly became obvious that whoever was able to best enhance their flight strength would have the upper hand in the wars of the latter half of the twentieth century, and as the Cold War began hotting up (no pun intended) engineers across the world began turning their hands to problems of air warfare.

Take, for example, the question of speed; fighter pilots had long known that the faster plane in a dogfight had a significant advantage over his opponent, since he was able to manoeuvre quickly, chase his opponents if they ran for home and escape combat more easily. It also helped him cover more ground when chasing after slower, more sluggish bombers. However, the technology of the time favoured internal combustion engines powering propeller-driven aircraft, which limited both the range and speed of aircraft at the time. Weirdly, however, the solution to this particular problem had been invented 15 years earlier, after a young RAF pilot called Frank Whittle patented his design for a jet engine. However, when he submitted this idea to the RAF they referred him to engineer A. A. Griffith, whose study of turbines and compressors had lead to Whittle’s design. The reason Griffith hadn’t invented the jet engine himself was thanks to his fixed belief that jet engines would be too inefficient to act as practical engines on their own, and thought they would be better suited to powering propellers. He turned down Whittle’s engine design, which used the forward thrust of the engine itself, rather than a propeller, for power, as impractical, and so the Air Ministry didn’t fund research into the concept. Some now think that, had the jet engine been taken seriously by the British, the Second World War might have been over by 1940, but as it was Whittle spent the next ten years trying to finance his research and development privately, whilst fitting it around his RAF commitments. It wasn’t until 1945, by which time the desperation of war had lead to governments latching to every idea there was, that the first jet-powered aircraft got off the ground; and it was made by a team of Germans, Whittle’s patent having been allowed to expire a decade earlier.

Still, the German jet fighter was not exactly a practical beast (its engine needed to be disassembled after every use), and by then the war was almost lost anyway. Once the Allies got really into their jet aircraft development after the war, they looked set to start reaching the kind of fantastic speeds that would surely herald the new age of air power. But there was a problem; the sound barrier. During the war, a number of planes had tried to break the magical speed limit of 768 mph, aka the speed of sound (or Mach 1, as it is known today), but none had succeeded; partly this was due to the sheer engine power required (propellers get very inefficient when one approaching the speed of sound, and propeller tips can actually exceed the speed of sound as they spin), but the main reason for failure lay in the plane breaking up. In particular, there was a recurring problems of the wings tearing themselves off as they approached the required speed. It was subsequently realised that as one approached the sound barrier, you began to catch up with the wave of sound travelling in front of you; when you got too close to this, the air being pushed in front of the aircraft began to interact with this sound wave, causing shockwaves and extreme turbulence. This shockwave is what generates the sound of a sonic boom, and also the sound of a cracking whip. Some propeller driver WW2 fighters were able to achieve ‘transonic’ (very-close-to-Mach-1) speeds in dives, but these shockwaves generally rendered the plane uncontrollable and they invariably crashed; this effect was known as ‘transonic buffeting’. A few pilots during the war claimed to have successfully broken the sound barrier in dives and lived to tell the tale, but these claims are highly disputed. During the late 40s and early 50s, a careful analysis of transonic buffeting and similar effects yielded valuable information about the aerodynamics of attempting to break the sound barrier, and yielded several pieces of valuable data. One of the most significant, and most oft-quoted, developments concerned the shape of the wings; whilst  it was discovered that the frontal shape and thickness of the wings could be seriously prohibitive to supersonic flight, it was also realised that when in supersonic flight the shockwave generated was cone shaped. Not only that, but behind the shockwave air flowed at subsonic speeds and a wing behaved as normal; the solution, therefore, was to ‘sweep back’ the shape of the wings to form a triangle shape, so that they always lay ‘inside’ the cone-shaped shockwave. If they didn’t, the wing travelling through supersonic air would be constantly being battered by shockwaves, which would massively increase drag and potentially take the wings off the plane. In reality, it’s quite impractical to have the entire wing lying in the subsonic region (not least because a very swept-back wing tends to behave badly and not generate much lift when in subsonic flight), but the sweep of a wing is still a crucial factor in designing an aircraft depending on what speeds you want it to travel at. In the Lockheed SR-71A Blackbird, the fastest manned aircraft ever made (it could hit Mach 3.3), the problem was partially solved by having wings located right at the back of the aircraft to avoid the shockwave cone. Most modern jet fighters can hit Mach 2.

At first, aircraft designed to break the sound barrier were rocket powered; the USA’s resident speed merchant Chuck Yeager was the first man to officially and veritably top 768mph in the record-breaking rocket plane Bell X-1, although Yeager’s co-tester is thought to have beaten him to the achievement by 30 minutes piloting an XP-86 Sabre. But, before long, supersonic technology was beginning to make itself felt in the more conventional spheres of warfare; second generation jet fighters were, with the help of high-powered jet engines, the first to engage in supersonic combat during the 50s, and as both aircraft and weapons technology advanced the traditional roles of fighter and bomber started to come into question. And the result of that little upheaval will be explored next time…

War in Three Dimensions

Warfare has changed a lot in the last century. Horses have become redundant, guns become reliable, machine guns become light enough to carry and bombs have become powerful enough to totally annihilate a small country if the guy with the button so chooses. But perhaps more significant than just the way hardware has changed is the way that warfare has changed itself; tactics and military structure have changed beyond all recognition compared to the pre-war era, and we must now fight wars whilst surrounded by a political landscape, at least in the west, that does not approve of open conflict. However, next year marks the 100th anniversary of a military innovation that not only represented massive hardware upgrade at the time, but that has changed almost beyond recognition in the century since then and has fundamentally changed the way we fight wars; the use of aeroplanes in warfare.

The skies have always been a platform to be exploited by the cunning military strategist; balloons were frequently used for messaging long before they were able to carry humans and be used for reconnaissance during the early 20th century, and for many years the only way of reliably sending a complicated message over any significant distance was via homing pigeon. It was, therefore, only natural that the Wright brothers had barely touched down after their first flight in ‘Flyer I’ when the first suggestions of a military application to such a technology were being made. However, early attempts at powered flight could not sustain it for very long, and even subsequent improvements failed to produce anything capable of carrying a machine gun. By the First World War, aircraft had become advanced enough to make controlled, sustained, two-person flight at an appreciable height a reality, and both the Army and Navy were quick to incorporate air divisions into their structures (these divisions in the British Armed Forces were the Royal Flying Corps and the Royal Naval Air Service respectively). However, these air forces were initially only used for reconnaissance purposes and ‘spotting’ for artillery to help them get their eye in; the atmosphere was quite peaceful so far above the battlefield, and pilots and observers of opposing aircraft would frequently wave to one another during the early years of the war. As time passed and the conflict grew ever-bloodier, these exchanges became less friendly; before long observers would carry supplies of bricks into the air with them and attempt to throw them at enemy aircraft, and the Germans even went so far as to develop steel darts that could reportedly split a man in two; whilst almost impossible to aim in a dogfight, these darts were incredibly dangerous for those on the ground. By 1916 aircraft had grown advanced enough to carry bombs, enabling a (slightly) more precise method of destroying enemy targets than artillery, and before long both sides could equip these bombers with turret-mounted machine guns that the observers could fire on other aircraft with; given that the aircraft of the day were basically wire and wood cages covered in fabric, these guns could cause vast amounts of damage and the men within the planes had practically zero protection (and no parachutes either, since the British top brass believed this might encourage cowardice). To further protect their bombers, both sides began to develop fighter aircraft as well; smaller, usually single-man, planes with fixed machine guns operated by the pilot (and which used a clever bit of circuitry to fire through the propeller; earlier attempts at doing this without blowing the propeller to pieces had simply consisted of putting armour plating on the back of the propeller, which not infrequently caused bullets to bounce back and hit the pilot). It wasn’t long before these fighters were given more varied orders, ranging from trench strafing to offensive patrols (where they would actively go and look for other aircraft to attack). Perhaps the most dangerous of these objectives was balloon strafing; observation balloons were valuable pieces of reconnaissance equipment, and bringing them down generally required a pilot to navigate the large escort of fighters that accompanied them. Towards the end of the war, the forces began to realise just how central to their tactics air warfare had become, and in 1918 the RFC and RNAS were combined to form the Royal Air Force, the first independent air force in the world. The RAF celebrated its inception three weeks later when German air ace Manfred von Richthofen (aka The Red Baron), who had 80 confirmed victories despite frequently flying against superior numbers or hardware, was shot down (although von Richthofen was flying close to the ground at the time in pursuit of an aircraft, and an analysis of the shot that killed him suggests that he was killed by a ground-based AA gunner rather than the Canadian fighter pilot credited with downing him. Exactly who fired the fatal shot remains a mystery.)

By the time the Second World War rolled around things had changed somewhat; in place of wire-and-fabric biplanes, sleeker metal monoplanes were in use, with more powerful and efficient engines making air combat faster affair. Air raids themselves could be conducted over far greater distances since more fuel could be carried, and this proved well suited to the style of warfare that the war generated; rather than the largely unmoving battle lines of the First World War, the early years of WW2 consisted of countrywide occupation in Europe, whilst the battlegrounds of North Africa and Soviet Russia were dominated by tank warfare and moved far too fluidly for frontline air bases to be safe. Indeed, air power featured prominently in neither of these land campaigns; but on the continent, air warfare reigned supreme. As the German forces dominated mainland Europe, they launched wave after wave of long distance bombing campaigns at Britain in an effort to gain air superiority and cripple the Allies’ ability to fight back when they attempted to cross the channel and invade. However, the British had, unbeknownst to the Germans, perfected their radar technology, and were thus able to use their relatively meagre force of fighters to greatest effect to combat the German bombing assault. This, combined with some very good planes and flying on behalf of the British and an inability to choose the right targets to bomb on behalf of the Germans, allowed the Battle of Britain to swing in favour of the Allies and turned the tide of the war in Europe. In the later years of the war, the Allies turned the tables on a German military crippled by the Russian campaign after the loss at Stalingrad and began their own orchestrated bombing campaign. With the increase in anti-aircraft technology since the First World War, bombers were forced to fly higher than ever before, making it far harder to hit their targets; thus, both sides developed the tactic of ‘carpet bombing’, whereby they would simply load up as big a plane as they could with as many bombs as it could carry and drop them all over an area in the hope of at least one of the bombs hitting the intended target. This imprecise tactic was only moderately successful when it came to destruction of key military targets, and was responsible for the vast scale of the damage to cities both sides caused in their bombing campaigns. In the war in the Pacific, where space on aircraft carriers was at a premium and Lancaster Bombers would have been impractical, they kept with the tactic of using dive bombers, but such attacks were very risky and there was still no guarantee of a successful hit. By the end of the war, air power was rising to prominence as possibly the most crucial theatre of combat, but we were reaching the limits of what our hardware was capable of; our propellor-driven, straight wing fighter aircraft seemed incapable of breaking the sound barrier, and our bombing attacks couldn’t safely hit any target less than a mile wide. Something was clearly going to have to change; and next time, I’ll investigate what did.

How Quantum Physics Explains Action Films

One of the key ideas used by cosmologists (yes, physics again, sorry) to explain away questions asked by annoying philosophical types is known as the anthropic principle. This has two forms (strong and weak) but the idea remains the same for both; that the reason for a situation being as it is is because, if it wasn’t, we wouldn’t be around to ask that question. For example, one might ask (as Stephen Hawking did in ‘A Brief History of Time’) why the universe is around 10 billion years old, a decidedly awkward question if ever there was one. The anthropic principle provides the simplest answer, stating that since organic life is such a complicated business and that the early universe was such a chaotic, unfriendly place, it is only after this vast amount of time that life forms capable of asking this question have been able to develop.

This answer of ‘because we’re here’ is a wonderfully useful one, albeit one that should be used with caution to avoid not answering valid question, and can be applied to problems that do not concern themselves directly with physics. One example concerns the origin of the human race, as we are all thought to stem from just a few hundred individuals who lived in East Africa’s Rift valley several million years ago. At that time our knowledge of weapons, fighting and general survival was relatively scant, and coming face to face with any large predator would have been a fairly assured death sentence; the prehistoric equivalent of a smart pride of lions, or even some particularly adverse weather one year, could have wiped out a significant proportion of the human race as it stood at that time in just a few months. Despite the advantages of adaptability and brainpower that we have shown since, the odds of natural selection were still stacked against us; why did we arise to become the dominant multicellular life form on this planet?

This question can be answered by listing all the natural advantages we possess as a species and how they enabled us to continue ‘evolving’ far beyond the mere natural order of things; but such an answer still can’t quite account for the large dose of luck that comes into the bargain. The anthropic principle can, however, account for this; the human race was able to overcome the odds because if we hadn’t, then we wouldn’t be around to ask the question. Isn’t logic wonderful?

In fact, one we start to think about our lives and questions of our existence in terms of the anthropic principle, we realise that our existence as individuals is dependent on an awful lot of historical events having happened the way they did. For example, if the Nazis had triumphed during WWII, then perhaps one or more of my grandparents could have been killed, separated from their spouse, or in some way prevented from raising the family that would include my parents. Even tinier events could have impacted the chance of me turning out as me; perhaps a stray photon bouncing off an atom in the atmosphere in a slightly different way could have struck a DNA molecule, causing it to deform the sperm that would otherwise have given me half my genes and meaning it never even made it to the egg that offered up the other half. This is chaos theory in action, but it illustrates a point; for the universe to have ended up the way it has depends on history having played out exactly as it has done.

The classic example of this in quantum physics is the famous ‘Schrodinger’s Cat’ experiment, in which a theoretical cat was put into a box with a special quantum device that had a 50/50 chance of either doing nothing or releasing a toxic gas that would kill the cat. Schrodinger’s point was that, when the cat is put into the box, two universes emerge; one in which the cat is dead, and one in which it is alive. Until we open the box, we cannot known which of these universes we are in, so the cat must be thought of as simultaneously alive and dead.

However, another thought experiment known as the ‘quantum suicide’ experiment takes the cat’s point of view; imagine that the cat is an experimenter, and that he is working alone. Imagine you are that experimenter, and that you had stayed in the box for five iterations of the 50/50 life/death random event. In 31 out of 32 possible futures, you would have been gassed, for at least once the device would have selected the ‘death’ option; but in just one of these 32 alternative futures, you would still be alive. Moreover, if you had since got out of the box and published your results, the existence of those results is solely dependent on you being that lucky one out of 32.

Or, to put it another way, consider a generic action hero, in the classic scene where he runs through the battlefield gunning down enemies whilst other, lesser soldiers fall about him from bullets and explosions. The enemy fire countless shots at him, but try as they might they can never kill him. They try, but he survives and the film reaches its triumphant conclusion.

Now, assuming that these enemies are not deliberately trying to miss him and can at least vaguely use their weapons, if our action hero tried to pull that ‘running through a hail of bullets’ stunt then 999 times out of a thousand he’d be killed. However, if he was killed then the film would not be able to reach its conclusion, since he would be unable to save the heroine/defeat the baddie/deliver a cliched one-liner, and as such the story would be incomplete.  And, with such a crappy story, there’s no way that a film would get made about it; therefore, the action hero must always be one of the lucky ones.

This idea of always triumphing over the odds, of surviving no matter what because, if you didn’t, you wouldn’t be around to tell the tale or even be conscious of the tale, is known as quantum immortality. And whilst it doesn’t mean you’re going to be safe jumping off buildings any time soon, it does at least give yo a way to bore the pants off the next person who claims that action movies are WAAYYYY too unrealistic.

Oh, the weather outside is frightful…

At the time of writing, it is snowing outside (which should give some of you an idea as to the length of backlog I keep). All I see is some varying shade of white or grey, as the snow lies several inches deep in patches- and is still falling. Even the road is barely visible between its white dusting. All is calm, all is quiet, all sound deadened in that weird way snow does.

This has, understandably, somewhat altered my plans over the weekend. With all rugby-related activities off for the immediate future and a large repository of awesome awaiting in the hills near my home, I have spent around four hours over the last two days rolling around in, sliding over, throwing and falling into heaps of snow whilst wrapped in twice the layers of clothing I customarily wear; and loving every minute of it. Monday has come inconveniently early for me. I am a big child.

Of course, snow is not all great news. When the snow first fell I was stuck away from home and offered to give a friend a lift back to his; after I’d dropped him off I became caught in the worst traffic jam I have ever experienced, and took a total of three and a half hours to get to my house, eight miles from my point of departure. This is just one part of the minor infrastructure  meltdown that occurs whenever snow ends up where it’s unexpected; across Britain (where, incidentally, this decade has seen more serious snowfalls than the last half-century) roads have been clogged, schools have closed, airports have had to cancel flights and shops have shut. After a few days most people have basically got used to it and some aspects of life are starting to return to normal, but the smaller roads are still treacherous and flights continue to be cancelled across the country.

This of course inspires the usual parlance of “we are all a bunch of useless wusses, why is the country grinding to a halt, in Canada/Sweden/Switzerland/the mountain passes of Tibet they can deal with this pitiful dusting in their sleep”. This is generally an opinion put forward by a) raging pessimists who hate everything and b) people who are angry at having been stuck in traffic or similar for an extended period, and is somewhat stupid. In countries where snow is regular/predictable/all the year round, people have all the equipment (winter tyres, snow chains, snowploughs etc.) to make sure they can cope when the inevitable bad weather rolls in. In Britain however, snow is so irregular and unpredictable that to own all this expensive equipment is simply not financially viable to keep all year round, much less remember how to equip and use. If we just take the economic standpoint, despite the chaos it causes, we are better off in the long run having a few days every year or three of total mayhem than an expensive state of perpetual readiness that we really don’t need.

The fact that this sentiment exists, however, is indicative of the strange love/hate relationship we have with snow. On the one hand, we idolise it; we holiday across continents to spend weeks slithering around over a predictable supply of it, hail snowy landscapes as some of the most breathtakingly beautiful our planet has to offer, and every year as December rolls around we in the Northern hemisphere are greeted to endless images of snow in adverts, TV and everything else even remotely associated with Christmas. In this context, it is seen as a kind of wistful image; a wish for the snow’s beauty and the kind of landscape to make a crackling fire and time spent with the family seem even more attractive and like the perfect family Christmas that we all seem to aim for during the festive period. Snow is something to be lusted after, something we are willing to pay an awful lot for, and that has some kind of mystical quality to it.

But then we consider the inverse; what happens when it arrives. Across the country, news bulletins offer us stern warnings of icy roads, treacherous conditions, the occasional serious incident (this year four people were killed in a hiking incident during the worst part of the cold weather) and, of course, the thousands of parents facing childcare problems as little Timmy’s school has shut and he wants to go play in the snow. When it comes around, the number of people who say they hate snow grows rapidly; it traps us in traffic, riles our tempers, messes with our schedules. The snow itself, so pristine when it first falls on fresh, cold ground, rapidly becomes compressed down to slippery, dirty ice, before turning into a messy slush. For many, there is no option but to wrap up warm, stay indoors and curse the day God invented the ‘cold rain’ (as a mate recently described it).

To an extent, this is an age thing; when young, we yearn for the snow that is so often promised but never comes, and without the responsibilities of adulthood we are fully equipped to make the most of it when it comes round. To an adult, being unable to get to work is frustrating and inconvenient; but a closed school is a child’s paradise, and offers an excuse to spend the entire day messing around doing as you please. And not only that, but the weather has also provided the best playground imaginable; not only is snow soft and relatively harmless, but it can be easily compacted into a harder, more solid form, allowing it to form snowballs, snowmen and even makeshift igloos. Even better than that, snow is mighty slippery stuff, allowing us to go flying down hills far faster than we could hope to even sprint, whilst still being soft enough to break our fall and clean enough that we don’t have to worry about ruining clothes, adding sledding to the ‘snow play’ repertoire.

Perhaps children are simply those best equipped to enjoy the snow; they don’t have to worry about the roads or work, and have none of the adult responsibilities that so weigh our older selves down. Or maybe they just have the correct mindset to deal with it, because in all honesty, snow is really good fun; a form of entertainment that is great precisely because it comes around so rarely, and provides so many opportunities. Maybe I’m just a big kid, but to me snow is a chance to forget a few of my responsibilities for a while, and just have fun bouncing off the trees. To return to the mind of a child one again, but with the adult body that allows me to get the absolute most out of it.