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  1. AeroGavin

    Transition Reynold's Number Range

    Thanks for the info! I'm assuming that this is a clean aircraft (no landing gear, pylons, et cetera). However, due to the fact that Re is below critical Re (<500,000) for the wings and above critical Re for the fuselage, I seem to be getting higher profile drag contributions from the wings...
  2. AeroGavin

    Helicopter Performance (4k/95)

    Let me restate my comments on the temperature. The 95 degF is the temperature at sea-level. In your calculation for air density at altitude, you will need to either determine the temeperature at 4,000 ft or use an equation that accounts for the temperature fall with altitude. Sorry about...
  3. AeroGavin

    Transition Reynold's Number Range

    If you calculate the Reynold's number of the fuselage to be about 10^6 and the wings to be about 3e5 of a high-speed, small-scale aircraft, is it possible to have a higher profile drag on the wings than the fuselage? I'm not sure if being on opposite sides of the critical Reynold's number would...
  4. AeroGavin

    Helicopter Performance (4k/95)

    "It surely will not be 95 deg. F at 4,000 ft. pressure altitude." Actually, it can be 95 degF at 4,000 ft above sea-level. Think about Denver, CO. If you're on the ground, your altitude is around 5,000 ft above sea-level. The Army High/Hot conditions are talking about altitude above...
  5. AeroGavin

    Transition Reynold's Number Range

    If you calculate the Reynold's number of the fuselage to be about 10^6 and the wings to be about 3e5 of a high-speed, small-scale aircraft, is it possible to have a higher profile drag on the wings than the fuselage? I'd appreciate any help on the subject, and would love to get references with...
  6. AeroGavin

    Helicopter Performance (4k/95)

    To meet the Army High-Hot standard (4,000 ft, 95 degF) you have to prove that you can hover out-of-ground-effect (OGE). For Army standards you also must have a 500 ft/min rate of climb capability. For hand calculations follow this format: 1. Get Power available @ altitude a...

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