The Cuzaux effect. Cazaux. Whatever

A most interesting query and ensuing discussion over on the H-War mailing list, about the so-called "Cuzaux effect", which I haven't heard of before:

In short, [the Cuzaux effect] is the side ways deviation of
a projectile trajectory when fired from a weapon in motion. In the late 1930's, according to the article, it was discovered that this effect became so strong when a the bomber achieved the speed of 320 km/t and over, that its defensive armaments would have great difficulties when trying to hit an attacking fighter which came in with an angle larger than 30 degrees to the bomber's own course. This was supposed to be one of the major blows to the so-called bomber-paradigm, formulated among others by British politician Stanley Baldwin in his words the bomber will always get through (1932). According to this, the speed, climbing rate and operational ceiling of bomber relative to fighter preformance were developing in favor of the former. Combined with heavy defensive weaponry, the bomber would be virtually invulnerable to fighter attack. In the Spanish civil war, it was discovered that even slower but more maneuverable biplanes were able to down faster bombers, and even fighters.

The above was written by Frode Lindgjerdet, who is writing a thesis on airpower theory in Norway in the interwar period, and came across the Cuzaux effect in an article from 1939 (no reference given).

Erik Lund provided the most informative reply: it's probably spurious (it has to do with conservation of angular momentum, and the gyroscope equations -- that takes me back!). Though I'm not sure about his remark that 'it certainly did not refute the bomber orthodoxy, since it is a myth'. Myths can be influential too, so I don't think it necessarily follows that the putative Cuzaux effect could not have ended the belief that the bomber will always get through. It may have done, for some people, whether erroneously or not, or at least caused them to reconsider the bomber paradigm (the dominance of which anyway can be overstated; see, eg, John Ferris, "Fighter defence before Fighter Command: the rise of strategic air defence in Great Britain, 1917-1934", Journal of Military History 63 (1999), 845-84). It may not have filtered down to the public, though -- a keyword search of The Times yields no hits for "Cuzaux". Something to file away for future reference.

Update: the perils of liveblogging a mailing list. Firstly, it looks like the correct spelling is Cazaux, as there is a French military test airfield with that name, as Jonathan Beard pointed out (there are hits for this spelling in The Times now, though none relating to any Cazaux effect). And two posters (Ed Rudnicki and Will O'Neill) have pretty convincingly argued that the effect was not in fact mythical, but was already known of (it was called "jump", at least by the Americans) and could be corrected for to a large extent by the more sophisticated gunsights.

Update 2: Further informative posts from Will O'Neill and Erik Lund.

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5 thoughts on “The Cuzaux effect. Cazaux. Whatever

  1. In the Anglosphere, a crucial point about aerial gunnery was that the ranges involved were systematically overestimated for years. RAF fighter tactics were based on an expected range of 400 yards and this was worked into the codified set of Fighting Area Attacks, a sort of drillbook approach to air combat. Attack No.1 had a section of fighters follow their leader in line astern up to a bomber, and take it in turns to shoot before breaking off in a 120 degree turn.

    (Think: similar to the coordinated break that you see in every movie involving fighters, where the aircraft turn away showing their bellies to the camera.) In practice this was unworkable - it didn't help that the break involved presenting a very large target with little relative momentum to any air gunner on the target for several seconds, either.

    In the test of action, RAF Fighter Command rapidly junked it and appropriated the German schwarm/rotte formations and greater independence of action. This was all based on the principle that engagement was likely at much shorter ranges and hence that a stable gun platform was less important. Further, most squadrons had re-zeroed their guns from the officially prescribed 400 yard harmonisation to 250 yards by the end of the Dunkirk campaign (although the bureaucracy took a while longer to soak this up)

  2. Brett Holman

    Post author

    Thanks, Alex. I always find it difficult to understand why it was so hard to evolve more sensible tactics in peacetime. Obviously there's nothing like a real war to hurry things up, but surely there was a lot that could be learnt from exercises, gun cameras and aerial targets.

  3. Partly because the Germans had a live try-out in Spain, which is where the schwarm/finger-4 was invented.

    In one of the standard BoB works, there's a nice anecdote about some bureaucratic imbecile who turned up at Hornchurch in late August, 1940 to demand why Al Deere's squadron didn't have their guns harmonised as laid down in the book.

  4. Brett Holman

    Post author

    Granted, but what I mean is, even in the absence of operational experience, why couldn't operational research methods have been used by the RAF to weed out the less sensible tactics? I would have thought that exercises would have shown that, for example, the wingmen in a vic were expending far too much effort keeping in formation, and not enough watching out for the enemy.

  5. That depends on the assumptions that go into setting up the exercise - if the "opposing" fighters are using the same tactics, the results will be of little use.

    One reason it survived, I think, was the utility of all that formation flying as training.

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