Recent content by dtango

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    Power available vs Power required ?

    Hmm, you're missing some info. What's the maximum level airspeed you want the plane to fly at altitude? Parasite drag increases with the square of velocity which means power required increases the faster you go. 2ndly if this is a prop aircraft propeller efficiency also varies with velocity...
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    Explaining Pleasezzzz: A Guide

    Baaah, what's so scary about boundary layers? :devil: *cough* *cough* Good point however! :smile:
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    Calculating Propeller Thrust Using Given Data

    For your given situation you can use the following relationships to solve for thrust. http://www.mh-aerotools.de/airfoils/propuls3.htm
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    Biplane vs Monoplane: Which has Greater Drag & Why?

    I don't know of an easy way of evaluating that not requiring some fancy maths or wind-tunnel tests to know for sure. In general though, purely spherical objects tend to be pretty draggy. http://thetongsweb.net/images/Cd_v_NR.jpg image source...
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    Explaining Pleasezzzz: A Guide

    Hehe, I liked your response. To the OP, what boneh3ad is saying is that the main constraint for bernoulli is the flow is inviscid. To account for viscosity things get more complicated such as using N/S equations to deal with what occurs in viscous flows. For an application of this, look...
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    Why air is compressed in Gas turbine engine ?

    1) Turbojets produce more thrust at high mach numbers 2) Turbojets have a higher thrust-to-weight ratio compared to turbofans These two factors lend to design choices when you want a missile to get to the target as fast as possible. The trade off is range where turbofans give you higher...
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    Explain the pressure terms in Bernoullis Equation

    StartlerBoy, you're trying to hard :wink:. Boneh3ad and I obviously think the same. We've both answered your question about the change in static pressure by using the kinetic molecular model to describe what's going on at a molecular level which applies for fluids (liquids and gases). I...
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    Explain the pressure terms in Bernoullis Equation

    It's means the same thing in H20 or a gas, momentum change as a result of the random motion of the molecules whether gas or water. Static pressure is the measure of force from the random motion of the molecules. When the fluid is in motion, there is order introduced because of the direction...
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    Prithvi-II fails to take off in user trial

    You're probably right about that. Probably didn't want to lose their telemetry gear :).
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    Prithvi-II fails to take off in user trial

    Hmmm, that's sort of odd in my opinion...seeing that Prithvi II is a freakin' ballistic nuclear missile. That nose-cone thingy would be the nuclear warhead. :confused:
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    Is a Marginally Stable Airplane Safe?

    Of course you have! :smile: You just didn't know it. I'm sure you were taught about CG movement for an airplane and the need to be sure how far aft the CG may move- for instance as you add passengers and bags for a GA airplane. CG moving aft of the neutral point means bad juju!
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    Caspian Sea Monster vs Conventional Airlift

    mugaliens - on a tangent, wow sorry you were friends with some of those onboard the B-52 that crashed at Fairchild. I've read "Darker Shades of Blue". The crash was made that much more senseless and tragic. I can't imagine how hard it was for Col Robert Wolff's family he waited for him on the...
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    Flying Wing Aircraft: Hand Launch Climb Necessity?

    Wow! Spectacular flying of those gliders especially in the 2nd video! Thanks for sharing. There must be some serious ridge lift on the side of cliff there where they are flying to be able to gain as much altitude and energy to perform the maneuvers they do.
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    Biplane vs Monoplane: Which has Greater Drag & Why?

    Your welcome! You should review it anyway though in case you want to elaborate. I left out all the juicy stuff in my foggy cliff notes version after I glanced at it yesterday!
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    Caspian Sea Monster vs Conventional Airlift

    I've always thought that Russian WIG craft was pretty cool. However one of the downsides to the practicality of such craft is you need a pretty flat stable surface for them to work well. Imagine that thing trying to cross the North Atlantic in a storm with 30-50 ft swells...
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