The Messerschmitt Me 163
The Komet, from Messerschmitt was a last ditch resort by the Luftwaffe to defend German airspace from the massive formations of American and British bombers dropping millions of pounds of explosive onto German factories and cities. Perceived as a weapon that used (at the time) the most advanced jet technology around: rocket propulsion. Chemists in the Reich’s top laboratories discovered that combusting hydrazine when in contact with pure oxygen resulted in a powerful explosion that when directed, say out of a nozzle on a rocket, provided massive amounts of thrust. In addition, hydrazine was relatively quick to produce in Germany’s now weak and slow production industry, so access to readily available fuel partially eliminated quite a few problems.
Design
The fighter itself was designed by Alexander Lippisch, one of the most forward looking aeronautical engineers of his era, and featured a delta wing design, with all other control surfaces such as the elevator incorporated into the main wing. It was extremely small as well, being just large enough to feature an efficiently small cockpit and fuel, along with two mk 108 cannons in the 30 mm caliber, a compact version of the far superior mk 103 cannon also produced by Rheinmetall-Borsig.
Delta Wings: Not Your Typical WW2 Design
The most important feature of the design was the rounded delta wing, although a passed-over design today, with the tools and for the types of aerial battles fought then it reflects an interesting merger of slow speed performance as well as, well, structural tolerance at it’s speed limits (800–940 km/h). The rounded ends and general non-linearity of the leading and trailing edge as seen here performed a similar task as those of the British Spitfire: they allowed for the plane to climb more steadily at quite insane angles of attack, even compared to today’s fighters. To understand why it was extremely necessary to round the delta wing, the principle of boundary-layer airflow should be studied. Put simply, it is the behavior in which a fluid steam interacts with airfoils. As the Germans did not have access to modern wind tunnels or other tools besides the basic Navier-Stokes equations, (see my whole geek-out on N-S eq’s here) Alexander Lippisch and his team didn’t incorporate laminar structure for their wings. However, the partially solved the problem with errant and turbulent flow by incorporating a raised spar along the chord of each wing, which divides the airflow into two relatively similar streams that, if referring to The Navier-Stokes, should reduce the overall turbulence by a factor of two! Now, the more astute readers would notice that the turbulence of a small, thin and (relative to the rest of the aircraft) large area wing should have no problem dealing with turbulence as the vorticity of the stream would only become severe after it left the wing, thus only causing problems for planes right behind it. That is partially true, but it is important to remember that at high Reynolds numbers, where turbulence upon contact with the leading edge results in shaking that can be solved with a well placed and sturdy elevator, that this is a delta wing design! Once the airflow around the wing begins to seperate and buffet the main wing, there are no second chances! Makes a little sense, right? As a whole, the design is surprisingly efficient for the resources available at the time, and its purpose as an interceptor that had to respond to threats and be at combat altitude in under ten minutes. As a whole, many people agree that the 163 is one of the most interesting and well designed rush jobs in the world!
