Neilster
Posts: 2890
Joined: 10/27/2003 From: Hobart, Tasmania, Australia Status: offline
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quote:
ORIGINAL: Froonp quote:
My alternative-history Luftwaffe, in which a radical canard-pusher He 112 is built in preference to the Me 109 in many variants, looks like it's coming together Are you saying that this canard winged pusher plane is a He 112 ???? I beg to differ, the He 112 is not that plane. A He 112 is this (see illo) But what is that plane ? I know what the historical He 112 is. It's actually an oddball favourite of mine. This aircraft is one I designed for fun; the He 112 Kobra. My illustrations represent a He 112E fighter variant; in service in my alternative-history 1939 . Earlier models had more canopy framing, among other differences. The Kobra is actually a bit of a tribute to the historical He 112 because I think that aircraft was a little unlucky to lose out to the Me 109 in their fly-off. What got me thinking was that the DeHavilland Mosquito was a radical design in that, aside from being mainly constructed from wood, it eschewed turrets and relied on speed and manoeuvrability for defence. This flew in the face of conventional wisdom but proved to be a master stroke. In this case, basically all the designer’s assumptions turn out to be correct. Compare this to those made by the designers of the Boulton Paul Defiant or those massive French monstrosities of the mid 30s that were neither fighter nor bomber. Their assumptions turned out to be wrong, although in fairness, it wasn’t obvious at the time of their design. Now, although the best fighters of the mid 30s were developed into very capable aircraft, they suffered from poor range, bad ground handling (due to terrible forward vision from the cockpit on the ground, among other things), poor cockpit vision, vulnerability and compromised armament layouts (with limited space for ammunition and/or weapon firing rates limited by prop synchronisation). Before the Japanese began designing the Kyushu Shinden (Magnificent Lightning) in 1943, they realized that they would need to produce an exceptional aircraft to counter Allied numerical superiority. After analysing all possible configurations and keeping in mind the failings of current fighters, they decided on a canard-pusher as the best one. My idea was, “What if, someone designing a fighter in the mid 30s, someone had ‘done a mosquito’ and just happened to make radical design decisions that turned out to be correct?” The subsequent fighter would have been available in numbers by SEP/OCT 39 (to use a WiFism) and made a decisive difference. Since radical thinking was most common in Germany at that time and they get first crack at victory, in my alternative history, Heinkel designs such a He 112 and wins the fly-off against the Me 109. The canard-pusher layout has some disadvantages. I'll deal with them first. 1. It requires some kind of ejection seat or a system to detach the prop. Obviously, no-one was too keen to bail out of an aircraft with a big thrashing prop behind them. Ejection seats were in development anyway and a primitive one would have been easily doable with a determined effort in the mid 30s. The early ones were pretty low tech. 2. Having the prop at the back makes for a long undercarriage. I minimized the length of the main gear legs by using a Vought Corsair style gull-wing layout. A long nose undercarriage is required too but this is fairly light and rotates through 90 degrees as it retracts to lie under the nose armament. The P-47 Thunderbolt hydraulically compressed it's undercarriage to fit it into the wings, so that trick is available too. I haven't done a detailed undercarriage design yet. It has many advantages however. 1. You get a tricycle undercarriage. Ground handling from tail-dragging aircraft was so bad that tricycle undercarriages were being introduced on fighters by the late 30s anyway, as seen on the P-39. They also allow long loads like torpedoes to be carried easily. I designed the Kobra to give the pilot a good all-round view as this proved absolutely vital in combat. An accident of design enabled me to give the seat an F-16 style backward lean. This would be more comfortable on longer missions and facilitates “checking your six”. One of the major failings of WW2 era fighters was pilot comfort. Sitting behind a deafening engine in un-ergonomic discomfort for long periods was a nightmare. With its engine at the rear, the Kobra should be much quieter for the pilot. 2. Aerodynamic efficiency: Unlike a tail-dragger, both wing and foreplane provide lift. This means the wing can be made smaller, which reduces weight, which means the wing can be smaller, and so on. Canards generally also have nice stalling characteristics, being very forgiving. The fighters of WW2 often had vicious traits that killed many unwary pilots. A tail first design seems to generate space efficiencies too. I estimate that the Kobra will be able to carry much more internal fuel than an Me 109. No guns in the wings mean they could be used for fuel, especially on the recon variant. The wing and centreline are plumbed for drop tanks, enabling long range if required. 3. Generally, conventional fighters of the late 30s had, in the space behind the cockpit, very little except oxygen bottles and radios. In fighter vs fighter combat one was typically attacked from behind and these items were both very vulnerable and dangerous things to have hit. Not only that but before much armour was added, the pilot and any under-seat fuel tanks were extremely vulnerable. My rear-engined layout uses its huge metal mass to protect the main fuel tank, the radiator, the radios, the oxygen bottles and with the help of sloped armour above it and an armoured seat, the pilot from rear attack. Big 1930s/40s reciprocating engines were very tough. It was their radiators (unless air cooled) that were vulnerable. The Kobra’s prop spinner is armoured and the prop would probably be toughened up as well but props were rarely hit anyway. I incorporate some armour in the rear fuselage to help protect it too. Incidentally, although I would like to have chosen an air-cooled engine for their radically superior battle damage resistance, the Germans didn’t have a powerful enough one available in the mid 30s, so I went with the historical DB 600 series as used in the Me 109. 4. A canard-pusher configuration enables the armament to be concentrated in the nose. This has the advantage of concentrating firepower, providing more space for ammunition and allowing very long barrels that increase muzzle velocity and accuracy. A ground attack/tankbuster version could have a single, fairly rapid firing armour piercing/ high explosive cannon in the nose. Imagine what havoc such an aircraft with say, a 25mm gun, could have caused in 1939/1940. After dropping any bombs it would be almost as fast as the fighter version (allowing for a bit of extra drag from the gun and bomb racks) and just as manoeuvrable (perhaps more so at low level if it had clipped wings) so it would be hard to intercept. It would be a potent bomber destroyer too. Later on, as tanks get tougher, something like the historical 37mm anti-tank gun carried by the Stuka could be fitted. 5. In fact, a canard-pusher layout means that many variants could easily be created. Apart from fighters and the ground attack aircraft described, I can think of high altitude recon (long span wings, pressurised cockpit, wet wings, turbo-supercharger, nose camera), low altitude recon (more armour, clipped wings, nose camera) Carrier strike-fighter (naval equipment, stronger undercarriage, small torpedo capability, rockets) and two-seater trainer. The Luftwaffe could scrap a bunch of projects and concentrate on building as many Kobras as possible. One of the best aspects of a rear engine is that when turbojets are developed, it would be relatively easy to replace the piston engine with one without major redesign (He 212?). The ventral air intake that normally feeds the radiator, oil cooler and supercharger can become the jet intake. There’s plenty of room for a centrifugal turbojet or perhaps two axial ones. This should drastically reduce development problems as the rest of the aircraft would be basically unchanged. This was one of the reasons the Japanese chose this configuration. They planned a turbojet powered Shinden, designated the J7W2. Luft '46/Luftwaffe paper-planes are very popular and I enjoy studying them but in reality they would have been hacked out of the sky by swarms of P-80 Shooting Stars, Gloster Meteors and DeHavilland Vampires with highly trained pilots at the controls. My idea is for a kind of Luft '39 with variants of my He 112 Kobra replacing not just the Me 109 but the Ju 87 and some of the medium bombers as well. They were somewhat marginal anyway and the production capacity they required would be better used churning out heaps of fighter-bomber and ground attack He 112s. The Ju 88 would stay for carrying heavier bombs and missions requiring multiple crewmembers. The FW 190 was so good that it might be worth building anyway. Pilots used to a tricycle undercarriage probably wouldn’t enjoy going back to a tail-dragger though. Thanks Patrice for enabling me to explain my design. I had the huge advantage of knowing in advance what worked and what didn’t but it was still fun working out all the details. I've done some much more detailed drawings on paper but I'm still working on them. I’m also going to do a website with illustrations of the various versions, using historical unit markings and paint jobs. I’d like to do a virtual 3D model too but I don’t have the software or the skill. Cheers, Neilster Edit: to remove an error and a crappy plan view. It was my first draft and very rough.
< Message edited by Neilster -- 6/15/2007 3:29:01 AM >
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