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  • Aryajet
    replied
    Originally posted by Versus View Post
    Yep, that's the plan. An RC build from scratch. However, I've checked the prices yesterday, some things went up and some are not available (pending for tax and custom fees or are simply out of stock) so I don't know how long it will take me to build the thing. I was thinking to go with small steps and gradually progress towards more complex stuff, so the first airplane would be a glider (sailplane), small, hand launched with no control (free flyer as we call it here), than the bigger sailplane,controlled sailplane, powered sailplane and than the RC airplane. Constrains are many, knowledge and budget being at the top and than materials and machinery/tools being secondary. But I am learning everyday and I am determined to overcome them and get the design airborne. I will make a thread about it that will follow the progress, most likely tomorrow.

    Thanks for the advices,Tharos and Chogy much appreciated.
    If this is your first attempt on scratch building a RC plane then I suggest you start with a simple trainer plane with high wing and rudder elevator only. Later on if you think you need ailerons then you can cut them from the same wing. You will learn how to do this as you progress. The cheapest and most exciting way to do this is that you buy a full size plan from many sellers here in US and Europe as well. Check the links below. You can also enlarge or even make those plans smaller.

    Get yourself needed balsa and Plywood and start cutting. You won't need too many tools to do this. A set of small tools from Hobby outlets in the net or local shops will meet your need for start. Good lock to you and let me know if I can help I have over 20 years of building and flying RC planes under my belt.

    don Smith plans Precision Cut Kits

    Nick Ziroli plans http://www.ziroliplans.com/ziroliplans/welcome.html

    Leave a comment:


  • Aryajet
    replied
    Question about B-17 flying fortress.

    I stiil watch and enjoy 12 O'clock High (yah kinda old school) and many times I've noticed a box frame looking device which looks like a short ladder located on the bulkhead right behind pilot and copilot seats. While flying this thing seems continuously sliding left to right and vs. I've checked the net many times but no answer to my curiosity. What is that thing?

    Leave a comment:


  • Stitch
    replied
    Originally posted by Chogy View Post
    What we need is a wing that works like a bird - can reshape without requiring flaps, slats, etc, and especially can change camber on the fly.
    They did something like that back in the '80's with an F-111 test-bed; it was called the Mission Adaptive Wing, or MAW, though the latest incarnation is being called an Adaptive Compliant Wing (ACW?)

    Adaptive compliant wing - Wikipedia, the free encyclopedia.

    http://www.flxsys.com/pdf/NATO_Conf_Paper-KOTA.pdf

    Attached Files

    Leave a comment:


  • desertswo
    replied
    Originally posted by chanjyj View Post
    I can't quite discern your question, and I have not had much experience with naval flights. However, behind air power generation is a runway, so the dynamics are very different assuming that you haven't had forward air bases established.
    There is a truism I have experienced first hand. The first question the Chairman or SECDEF asks when entering the National Military Command Center (NMCC) during an international crisis is, "Where are the carriers?" The second is, "Where are the tanker bed downs." They are not idle questions. At the Strategy-Operational Art interface, the answers provide the way forward for the National Command Authority (NCA). Air Forces, whether naval or ground based, are about power projection. Being mobile allows naval aviation to operate in what are known as "immature theaters" of operations. The US Navy goes where it pleases and strikes where it pleases because they take the airfield with them.

    Leave a comment:


  • chanjyj
    replied
    Originally posted by Doktor View Post
    Was always wondering behind the principle of Naval Air Forces.

    I understand they are needed for various support roles in the Navy and that the ops on water are different then those on land, but can't the same be said about the classical AF/Army constellation?
    I can't quite discern your question, and I have not had much experience with naval flights. However, behind air power generation is a runway, so the dynamics are very different assuming that you haven't had forward air bases established.

    Leave a comment:


  • Doktor
    replied
    Was always wondering behind the principle of Naval Air Forces.

    I understand they are needed for various support roles in the Navy and that the ops on water are different then those on land, but can't the same be said about the classical AF/Army constellation?

    Leave a comment:


  • Versus
    replied
    Originally posted by Chogy View Post
    You're welcome. May I suggest, as you progress on your plan, to NOT attempt a rudder-only RC version. Back in the very early RC days, rudder-only was a common setup due to budget, and it is a total PITA and not much fun at all to fly, a crash being almost inevitable. Got to be able to control pitch!

    Current RC equipment isn't too bad, cost-wise. An interesting option would be to cannibalize a 2-channel "toy", one of those very cheap ready to fly airplanes that are more toy than real model. But if the radio equipment works, bingo! Steal the radio stuff and put it in your own airplane. Be sure it is a proportional control - you move the stick "X" amount, and the servo moves a proportional amount.

    One truly fascinating arena these days is ultra, ultra miniature RC. Advances in radio eqipment, motors, and batteries has made the living room flyer a reality. The early jobs used pager vibrator motors, but they've gotten even smaller:

    [ATTACH=CONFIG]33248[/ATTACH]

    [ATTACH=CONFIG]33249[/ATTACH]

    Well actually, the electronics and the materials are not that expensive,they cost as much as in the US or elsewhere, but my income is rather thin. Now that is the problem if you go with the off the shelf solutions, but on the other hand it pushes the innovation which is a good thing. As long as love towards airplanes is there, way will be found to lift them up. This will be an interesting journey :)

    Leave a comment:


  • Chogy
    replied
    You're welcome. May I suggest, as you progress on your plan, to NOT attempt a rudder-only RC version. Back in the very early RC days, rudder-only was a common setup due to budget, and it is a total PITA and not much fun at all to fly, a crash being almost inevitable. Got to be able to control pitch!

    Current RC equipment isn't too bad, cost-wise. An interesting option would be to cannibalize a 2-channel "toy", one of those very cheap ready to fly airplanes that are more toy than real model. But if the radio equipment works, bingo! Steal the radio stuff and put it in your own airplane. Be sure it is a proportional control - you move the stick "X" amount, and the servo moves a proportional amount.

    One truly fascinating arena these days is ultra, ultra miniature RC. Advances in radio eqipment, motors, and batteries has made the living room flyer a reality. The early jobs used pager vibrator motors, but they've gotten even smaller:



    Attached Files

    Leave a comment:


  • Versus
    replied
    Originally posted by GGTharos View Post
    Are you building an RC? Anyway, in general you can choose a delta wing if you want the increased lift and instantaneous turn rate, but you will probably pay for it with other parameters. If you're de-emphasizing vertical maneuvering, you're probably compromising thrust, which means your delta wing might not fare too well in sustained turn rate (or any wing, really). The control surfaces don't factor into this, except perhaps that the size of your elevators/elevons will control how much you can move the nose. A big wing also has the ability to eclipse air flow to those controls, which you might guess is not a good thing - thus you see a lot of deltas equipping canards these days.



    Your servos need to be powerful enough to get your controls into position quickly and keep them there. So, the bigger a control surface like an elevator or aileron is, the more air resistance it encounters - and the more deflection, the more resistance again, so you have to account for that. For example the size of your ailerons may affect how quickly the plane will roll (among other factors, including their position on the wing for example), and the strength of the servos might have a small effect on how quickly you will develop maximum possible roll rate.
    Yep, that's the plan. An RC build from scratch. However, I've checked the prices yesterday, some things went up and some are not available (pending for tax and custom fees or are simply out of stock) so I don't know how long it will take me to build the thing. I was thinking to go with small steps and gradually progress towards more complex stuff, so the first airplane would be a glider (sailplane), small, hand launched with no control (free flyer as we call it here), than the bigger sailplane,controlled sailplane, powered sailplane and than the RC airplane. Constrains are many, knowledge and budget being at the top and than materials and machinery/tools being secondary. But I am learning everyday and I am determined to overcome them and get the design airborne. I will make a thread about it that will follow the progress, most likely tomorrow.

    Thanks for the advices,Tharos and Chogy much appreciated.

    Leave a comment:


  • GGTharos
    replied
    Originally posted by Versus View Post
    This is related to the up coming project.
    I would like to give advantage to the horizontal plane maneuvering, more precisely the turn rate while vertical plane is secondary concern. Does this mean that I have to pay attention to vertical stabilizer (tail and rudder) and wing ailerons ?
    Are you building an RC? Anyway, in general you can choose a delta wing if you want the increased lift and instantaneous turn rate, but you will probably pay for it with other parameters. If you're de-emphasizing vertical maneuvering, you're probably compromising thrust, which means your delta wing might not fare too well in sustained turn rate (or any wing, really). The control surfaces don't factor into this, except perhaps that the size of your elevators/elevons will control how much you can move the nose. A big wing also has the ability to eclipse air flow to those controls, which you might guess is not a good thing - thus you see a lot of deltas equipping canards these days.

    My guess is that I have to but just checking. Also what determines the plane responsiveness the electronics (aka avionics, servos) or the dynamic (control) surfaces? Clarification on the last one, do I have to buy a really fancy servos or pay more attention to the design of the control surfaces and go with the ordinary servos?
    Your servos need to be powerful enough to get your controls into position quickly and keep them there. So, the bigger a control surface like an elevator or aileron is, the more air resistance it encounters - and the more deflection, the more resistance again, so you have to account for that. For example the size of your ailerons may affect how quickly the plane will roll (among other factors, including their position on the wing for example), and the strength of the servos might have a small effect on how quickly you will develop maximum possible roll rate.

    Leave a comment:


  • Genosaurer
    replied
    Originally posted by Chogy View Post
    What we need is a wing that works like a bird - can reshape without requiring flaps, slats, etc, and especially can change camber on the fly.
    Haw - a century of aviation technology development and here we are, re-inventing wing warping.

    Leave a comment:


  • Chogy
    replied
    Originally posted by Maxor View Post
    Just for grins, why are current military aircraft trying to achieve STOL capabilities with purely engine/thrust based choices (Osprey, JSF) instead of lift based, (Flaps, Slats, variable geometry wings)?
    As mentioned, the weight, $$, complexity, and above all, the drag of such devices even when stowed. Plus, reduced RCS is going to be difficult with a complex wing using current technology.

    What we need is a wing that works like a bird - can reshape without requiring flaps, slats, etc, and especially can change camber on the fly.

    I would like to give advantage to the horizontal plane maneuvering, more precisely the turn rate while vertical plane is secondary concern.
    It is very hard to divorce the vertical from the horizontal, as the attributes you seek would affect both.

    To maximize turn rate, you'd want very low wing loading, a fuselage profile that contributes to lift, and massive elevator area. To SUSTAIN that turn rate, you need big numbers out of your powerplant, OR accept the fact that you'll be going downhill to keep the turn going. Does this make sense?

    Aileron area contributes to roll rate rather than turn rate. Vertical stabilizer - just enough to stabilize the aircraft. Too much is just additional, unwanted drag, although odd things can happen at higher AOA's that may warrant additional vertical stab area. Rudder - not too critical. A turn is 98% roll, then pull (elevator/stabilator). Rudder can keep it coordinated, but is not critical outside of sailplanes and lightly-loaded conventional aircraft.

    In a jet transport, the rudder exists for one reason, and that's engine-out work. I've never applied rudder outside that regime.

    Leave a comment:


  • Versus
    replied
    This is related to the up coming project.
    I would like to give advantage to the horizontal plane maneuvering, more precisely the turn rate while vertical plane is secondary concern. Does this mean that I have to pay attention to vertical stabilizer (tail and rudder) and wing ailerons ? My guess is that I have to but just checking. Also what determines the plane responsiveness the electronics (aka avionics, servos) or the dynamic (control) surfaces? Clarification on the last one, do I have to buy a really fancy servos or pay more attention to the design of the control surfaces and go with the ordinary servos?
    Last edited by Versus; 01 Jul 13,, 17:47.

    Leave a comment:


  • Jimmy
    replied
    My assumptions:

    Osprey - vertical capability
    JSF - drag, RCS, and the multitude of hassles of VG wings

    Leave a comment:


  • Maxor
    replied
    Just for grins, why are current military aircraft trying to achieve STOL capabilities with purely engine/thrust based choices (Osprey, JSF) instead of lift based, (Flaps, Slats, variable geometry wings)?

    Leave a comment:

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