5 ms·
What about the Tu-95? It's famously loud due to (says Wikipedia) supersonic propeller tips. Do you know why they're still effective?
by ahh 4y ago
What about the Tu-95? It's famously loud due to (says Wikipedia) supersonic propeller tips. Do you know why they're still effective?
- adolph 4y agoThe Tu-95’s props are paired for counter-rotational torque balance. The second prop does not add additional thrust.
- ahh 4y agoThe supersonic speed was the question, not the contrarotation.
- adolph 4y agoWell, samstave's original question was one of adding power with an inline stack. As I understood it, that isn't the purpose for he Tu-95's pair of props since they share a power source. The below explanation [0] has some interesting analysis based on Russian language documentation about how torque is divided between the prop pairs. Additionally the paper linked from the Wikipedia contra-rotating prop page "Analysis of a contra-rotating propeller driven transport aircraft" [1] has a great section on fuel savings, which probably has contributed to the Tu-95's success. Thus, the front prop gets almost 20% more torque than the rear prop. 0. https://aviation.stackexchange.com/questions/74787/why-dont-nk-12-powered-contra-rotating-propellers-turn-in-equal-rpm https://aviation.stackexchange.com/questions/74787/why-dont-... 1. https://www.rcgroups.com/forums/showatt.php?attachmentid=2815700 https://www.rcgroups.com/forums/showatt.php?attachmentid=281...
- samstave 4y agoThank you all TIL so much.
- samstave 4y agoI am convinced that if you were to dimple the propeller (tips) such as a golf ball is pitted, you would reduce this effect. Further, if you wer to dimple/convex in an alternating pattern the leading edge of any aero ... efficiencies would increase. Micro-dimples are better. Understand the eddys, as Da vinci would say....
- MichaelCollins 4y agoI believe they're sacrificing efficiency for performance.