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5

Jendrassik's own patent from 1939 does not go in-depth into the alloys. However, for the turbine blade legs he mentions "austenitic [stainless] steel" as preferable (see PDF page 3). From that era, a Swiss patent from 1937 on the materials of gas turbine parts also discusses austenitic steel, in particular (translated from German): Alloy of an austenitic ...


-1

What is the time frame ? Vitalium ( cobalt + chromium + Mo ) was one of the first turbine blade materials. Otherwise 50 % iron is not unusual ; for example the Incoloy group. But most of the high temperature materials have nickel as the major element . And contain Cr, Mo, Co , W , etc , and 1 to 20% iron. A temperature of 550 C / 1022 F is certainly not ...


5

Two worlds There are two elements constraining propeller use: The thrust we can get from a free propeller is lower than from a ducted fan at the same airspeed. Propeller efficiency quickly decreases with Mach number. Propeller performance vs speed. Source For these reasons fans are the natural choice for large and fast aircraft, and propellers for slower ...


0

Ice on airplanes causes two main problems. It adds weight and drag. It changes the shape of the aerodynamic surfaces. Problem 1 is fairly obvious. How serious a problem it is depends on the airplane and how fully loaded it is. If it is a problem, then ice needs to be removed from any or all surfaces to reduce the problem to an acceptable level. If the ...


28

The props are done before starting because you need to make sure the blades and spinners are fully cleaned off while they are stationary. Otherwise, they'd vibrate like hell when starting and shed bits of ice all over. Also, if you just sprayed the props while running the engines would ingest a lot of glycol, which, if it doesn't make the engine flame out, ...


5

Ice flying off the propellers can damage something, or someone. Also unbalances the propeller assembly overall, leading to vibrations. Little bit of ice left on the fuselage is not bad, only causes some extra drag until it sublimates off, and of course a little extra weight. Ice Will impact the lift created by the wings, that is very bad, unless the ice is ...


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