How did the Allies win WW2 in the air? This is a question which I've often pondered, and for some years I have been firmly convinced that luck played the greatest part. In technology terms, the decade prior to the the outbreak of hostilities between Germany and Poland on 1st September, 1939, was possibly the most significant in the twentieth century. The basic development of the jet engine, in both it's axial-flow and centrifugal forms in Great Britain and Germany, the impulse duct and the bi-fuel rocket ensured that new generations of aircraft would have the necessary advanced power plants. The almost simultaneous deployment of first generation radar equipment also seemed to point the way for a potent defensive system on both sides of the English Channel.
However, did the development and use of aerial weapons, airframes and much more importantly, aviation strategy and tactics keep up with the flow of technological inventions? Below find something to stimulate discussion and open the doors to the magical phrase 'what if?!'.
Let's take a brief look at the major Allied and Axis powers - ignoring date of entry into the conflict.
Great Britain and the Commonwealth
Plus: Massive experience in both air-cooled (Bristol) and liquid-cooled (Rolls-Royce) aero-engines. Excellent aerodynamics (see Schneider Trophy). World's first radar-controlled integrated air defence system (Chain Home and Chain Home Low).
Minus: Antiquated air fighting concepts (Fighting Area Attacks, 'V' fighter formations); bizarre fighter designs (turret fighters, Defiant and Roc, with no fixed-gun forward armament) in-fighting at the very top (virtually the whole Air Ministry vs Dowding). Poor bomber tactics (early daylight raids by Hampdens and Wellingtons with huge losses). Locked into use of WW1-calibre ammunition (and in some cases, guns), leading to poorly-armed bombers and fighters. Concept of 'the bomber will always get through' - former prime Minister Stanley Baldwin. Inability to recognise obsolescence (Fairey Battle, Bristol Blenheim). Sad neglect of naval aviation in general.
Plus: Massive investment in aero-industry due to secret planning for the conflict under a single leader. Brilliant designers and inventors (Willy Messerschmitt, Ernst Heinkel and others). First class aerodynamic research (see Me262). New stategy for the use of tactical air power (Blitzkrieg). Aircraft, manpower and tactics tried out in the Spanish Civil War. Excellent use of propaganda (He 100 dis-information campaign. Superb gun design (some German aircraft cannon designs are still in production TODAY). Superb radio and radar aids ('Y' system; Naxos). First use of jet and rocket aircraft; excellent air-to-air rockets.
Minus: Severe fragmentation of research effort (due to Reichluftfahrtministerium); political 'favouritism' at a high level (the He280 non-production fiasco). Emphasis on tactical aircraft production, e.g. Ju88 and He111 boosted, 'Ural' strategic bomber project cancelled. Awful leadership at the highest level, (Goering, Udet). Little aircrew rest; e.g. fighter pilots were sent to an active squadron and kept 'at the Front' until killed or promoted to a staff job.
Plus: Visionary aircraft (Bloch MB-155, Arsenal-Delanne 10);
proud heritage of WW1 units. Regular use of cannon in both fighters and bombers.
Minus: Appalling labour problems in a fragmented, semi-nationalised industry; slow modernization plans leading to massive US orders (NA DB-7, Curtiss Hawk 75); poor air force tactical organization.
Plus: Fascist state with high value placed on aviation propaganda (Balbo flights, etc.); excellent aerodynamics (see Schneider Trophy)
Minus: Low overall investment; low-power from engines; 'quirky' projects (see Caproni-Campini; 'oxygen' bomb) poor organisation. Wedded to biplane fighters (CR 42) and open cockpits (Fiat G50).
Plus: Massive industrial and manpower capacity; fine training organisation; first 400mph fighter (F4U Corsair); excellent research facilities.
Minus: Internal wrangling on tactics (bombardment vs pursuit vs tactical) Army vs Navy; overproduction of inappropriate designs (P-39, P-40); lack of good photorecon aircraft, and initially, radar. Brewster Aircraft!
Plus: Space! (to retreat into, to build factories in); heavy support from other Allies (ALSIB route, Murmansk convoys, etc); testing of aircraft/concepts in the Spanish Civil War; innovative use of the air-to-air and air-to-ground rocket; superb aircraft guns and cannon.
Minus: Antiquated designs initially; officer corps decimated by Stalin; taken by surprise by Germany's initial attack; predictable tactics; lack of radar.
Plus: Expansionist state supports war - extensive use of airpower in China from 1931; aerobatic designs such as the Mitsubishi Zero; fine naval aviation; fanatical self-sacrifice by aircrew.
Minus: Lightweight construction and lack of crew protection make for easy 'kills'; low-power cannon and low firepower in general; lack of radar; low industrial base; fanatical self-sacrifice by aircrew (!!)
Having set the scene, let's examine some outline case studies regarding Allied aviation in WW2.
The Fairey Battle fiasco.
During the late 1930's, it was fasionable for air arms to own large fleets of what were known as 'light bombers'. Typically carrying around 1,000lbs of bombs and with a crew of 2/3, these machines were usually underpowered and slow, and it was assumed that they would be defended by their own fighters. In the Battle of France, May/June 1940, Fairey Battles were exposed as death traps. Underarmed, they were shot down in droves, a whole squadron being destroyed during attacks on the bridges at Sedan. Despite this, Battles were kept in production, fortunately as training aircraft, although there were better aircraft available for the Commonwealth Air TRaining Scheme. The real irony of the situation is that the Hawker Henley was designed to the same specification, and this machine, which used the outer wing panels of the Hurricane and a the Rolls-Royce Merlin was much finer aerodynamically (c. 250mph). With a little development, the Henley could have become an excellent ground attack machine (or even a night-fighter/intruder), and could have taken advantage of all subsequent Merlin developments. Instead the few Henleys were relegated to target towing. A suggested solution would have been to have Fairey build the Henley!
Defiant, but that's all.
Strange ideas abound in aviation; the turret fighter was one of them. The Boulton Paul Defiant was an early turret specialist and the official specification which gave rise to the Defiant insisted that the sole armament of 4 x .303 machine guns be concentrated in a BP power-operated turret behind the pilot. The Defiant bore a slight resemblance to the Hurricane, and had used this to gain a signal victory over the Luftwaffe during the Dunkirk evacuation.
Sadly, this lack of forward firing armament lead to massive losses during the Battle of Britain. Later use of the Defiant included target tug and night fighter (virtually by default). This is one concept which should have been left on the drawing board.
With the availability of the British-built version of the 20mm Hispano cannon, some thought was given to a fighter to carry four of these guns to destroy raiding bombers. Eventually, the Hurricane was modified to carry the cannon, but another solution was the Whirlwind. First flown in 1938 and as fast as the early Spitfire, with it's cannon concentrated in the nose this twin-engined fighter had an Achilles heel - it's Rolls-Royce Peregine engines. Normally, Rolls-Royce engines meant good news for the designer, but this highly stressed development of the successful Kestrel engine was a really bad idea. On one of their first raids RAF Whirlwinds escorted Blenheims on a daylight raid over Germany - two were lost due to engine failure! Solution? Easy, re-stress/balance the airframe for the the incomparable Merlin and you have a world-beater.
Escort fighters? No thanks!
Regretably, some strategic decisions lead to really bad situations for the aircrew. Early on, it was decided by the Air Staff that RAF bombers could penetrate enemy airspace by reliance on mutually-supporting machinegun fire. This tactic was tried in early raids against Wilhelmshafen and Schilling Roads. Sadly, all that the defending Luftwaffe Me109's and 110's did was stand off beyond machinegun range and use 20mm cannon-fire to destroy most of the bombers.
Later, after the switch to night bombing, senior RAF opinion was that only short range interceptors were needed, hence the lack of underwing drop tanks for the Spitfire. A trial towards the end of the war using a Spitfire XIV fitted with an overload rear-fuselage tank, showed that by accepting slight longditudinal instability at the start of the sortie, a simulated escort to Berlin was possible. Unfortunately, the post-war market for long-range fighters was mostly left to secondhand Mustangs!
Machine guns or cannon?
Prior to WW2, the RAF possessed huge stocks of WW1 rifle-calibre machinegun ammunition (as well as using WW1 era Lewis guns in certain aircraft). Selection of a replacement for the other standard aircraft weapon, the Vickers .303 gun, emphasised the need to use up these stocks. Eventually, a Colt-Browning US design was modified to fire the rimmed GB cartridge, and eight of these guns were installed in the Spitfire and Hurricane fighters as well as in many turrets in heavy bombers.
Technical assessment showed that four of the larger Browning .5 caliber gun would have given far greater range, weight of shot as well as the ability to fire such rounds as API (armourpiercing/incediary). When weight of shot problems lead to many Luftwaffe aircraft surviving attacks during the Battle of Britain, it was realised that the only alternative was the 20mm cannon, which was undergoing installation and reliability problems.
The crime of Shrage Musik
During the second half of the war, RAF Bomber Command crews reported seeing many 'scarecrow shells' over Germany, AA shells where said to simulate the sight of an exploding four-engined bomber and designed to damage morale. Sadly, in many cases these were actual 'kills' by Luftwaffe nightfighters many using twin 20mm cannon installed at acute angle behind the pilot, and designed to fire upwards into the belly of the bomber. In was not for many months that evidence of these deadly attacks was accepted.
Initially, both the Halifax and Lancaster were designed with under-fuselage gun-mountings, but these were removed due to sighting problems. Some Lancasters were equipped in the field late in the war with a single, .5 calibre Browning operated in a simple mounting aft of the bombdoors, and manned by an extra crewman. It was almost criminal to allow so many casualties from Shrage Musik attacks.
The Martin Baker MB5
The Martin-Baker company developed a series of fighters, culminating with the MB5, which first flew in May, 1944. Possessed of outstanding performance (460mph at 20,000ft) and beautiful handling characteristics, the MB5 was praised, officially, by the Armament and Experimental Establishment. Everyone who flew the aircraft raved about it, and the MB5 would have seen service had an early decision been given. Failing that, it would have served the RAF and other air arms well in the post-war period. It is a mystery why this magnificent aircraft was not allowed to be manufactured.
The above studies only sample some aspects of the air war during the period 1939-1945. Doubtless, many others could be cited, but there is enough here to start the ball rolling!