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  1. #676

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    RE: Downwind turn Myth

    I,m sorry....I opened this forum and read it thinking it was the "mass confusion, argument, and debate forum" so I placed my comments here. I hate to start another forum. Seems they all end up like this one.

    BTW...I fly EDF jets...does that count?

    I had an actual talking dog once. I tried to sell him but ended up giving him away. He lied all the time!


    SPEEDY

  2. #677
    FILE IFR 's Avatar
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    RE: Downwind turn Myth

    ORIGINAL: highhorse

    My thanks to all who have contributed honest, thoughtful posts to the thread, whichever side you are on.

    The dog is now chasing it's, tail, so it's time to pull the plug on this wild, wild ride.

    I have PM'd Ken to request that he put a lid on the thread.

    Thanks again,
    Don Ray.

    Shall we motion to discontinue the teachings of aerodynamic facts to all nay-sayers?.. All in favor say aye.

    So say you Aussie Pelicans?... AYE!
    Mike * Intercepting The Localizer* AMA# 365566
    Bud Nosen C-310 Club #32 * J.P.O. Member 2302

  3. #678
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    RE: Downwind turn Myth


    ORIGINAL: FILE IFR

    ORIGINAL: highhorse

    My thanks to all who have contributed honest, thoughtful posts to the thread, whichever side you are on.

    The dog is now chasing it's, tail, so it's time to pull the plug on this wild, wild ride.

    I have PM'd Ken to request that he put a lid on the thread.

    Thanks again,
    Don Ray.

    Shall we motion to discontinue the teachings of aerodynamic facts to all nay-sayers?.. All in favor say aye.

    So say you Aussie Pelicans?... AYE!
    I just asked the Alaska pelicans...

    They said "YES, give us more fish and end this thread!"
    Alaska Bob - "Can I fly one of your jets? I crashed all of mine."

  4. #679

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    RE: Downwind turn Myth


    ORIGINAL: Tall Paul


    ORIGINAL: Lnewqban

    Pelicans don't let friends stall downwind
    .
    Watch the albatross take off!
    They just start running.
    Any old direction.
    Over anything in the way, including other birds.
    Sooner or later they get airborne, and become the most graceful soaring birds ever.
    They're also called ''Gooney birds'' because of their careless attention to takeoffs.
    So here is the question of the day??? If you have a load of pelicans in your airplane and you are too heavy to takeoff, if you get them flying in your airplane can you then takeoff?

  5. #680
    FalconWings's Avatar
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    RE: Downwind turn Myth


    ORIGINAL: BarksKT


    ORIGINAL: Tall Paul


    ORIGINAL: Lnewqban

    Pelicans don't let friends stall downwind
    .
    Watch the albatross take off!
    They just start running.
    Any old direction.
    Over anything in the way, including other birds.
    Sooner or later they get airborne, and become the most graceful soaring birds ever.
    They're also called ''Gooney birds'' because of their careless attention to takeoffs.
    So here is the question of the day??? If you have a load of pelicans in your airplane and you are too heavy to takeoff, if you get them flying in your airplane can you then takeoff?
    law of relativity. The mass of the airplane would be too large, thus eliminating any aspect of flight of the pelican relative to Earth. You would require a pull relative to earth to help lift the heavy airframe.
    Buying Jet Legend? Read here: http://www.rcuniverse.com/forum/m_11372496/mpage_1/key_/tm.htm

  6. #681

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    RE: Downwind turn Myth


    Comments in red.

    ORIGINAL: RZielin

    In response to FlytheSky's square loop puzzle:

    Sorry Flythesky, not to be condescending, you've made so many oversights and errors that it's kind of comical. You do indeed mix and confuse ground speed with airspeed in your description. But Isee that you do not describe them. You also do not define what you mean by "vertical" or "square loop". Do you mean square loop relative to the ground or square loop relative to the air mass?
    The common everyday square loop that is seen by an observor. They are two very different things in wind.

    I'll try to be helpful though. First, please note that you cannot truly turn "vertical" in a twenty knot wind. A true square loop is physically impossible in such a wind. You display a lack of experience to say that it is impossible, I do it all the time. You can EITHER pitch the plane up 90 degrees to a vertical pitch orientation, OR you can make the plane ascend vertically over the same patch of ground, BUT YOU CANNOT DO BOTH AT THE SAME TIME IN WIND. It is physically impossible. If you're tring to say that the plane can not be in a perfectly vertical orientation and ascend vertically in a wind, who cares, the goal is to have the plane ascend in a vertical line. In a wind you have to make corrections to fly a geometric shape. And my plane is in a pretty much vertical orientaion doing such manuvers.

    Option 1, the vertical climb relative to the ground: You'd have to pitch up at just the right angle (greater than 90 degrees) into and against the wind so that the wind would keep you ascending/hovering over the same spot of ground while you gain altitude. Pretty impossible to accomplish, but even if you could hit the angle right, the plane would not appear to be rising vertically like a rocket or a "normal" square loop. Again you display your inexperience, it's done all the time. It would appear to be ascending straight up relative to the ground while being pitched toward the canopy at a significant angle ("alpha"). You've never flown a plane that is capable of vertical lines have you? That's not quite what you intended in your description, You fail miserably as a mind reader. and not quite the vertical leg of a "square loop". As long as the plane is tracing a vertical line it is. In this scenario, you would gain a bit of headwind at the top when you pitch fully upwind, but not the full twenty knots. Part of that twenty knots was already being imparted to the plane as headwind on the up leg, because the plane was pitched into the wind on the way up. What you are saying is hardly the case. And any one familiar with just a decent sport plane would know that.


    This part is irrelevant. The common sense meaning of my post is intended.
    The only other option compatible with physical reality doesn't quite work for a "square loop" either. Option 2, the climb at vertical/90 degree angle of pitch: Simply pitching up at a 90 degree angle would result in the plane being blown downwind as it climbs. In this case, the plane would be pitched straight up (vertically pitched) but would not be ascending straight up over the same patch of ground. It would be moving up at a diagonal relative to the pilot and ground. Therefore when pitching fully upwind at the top of the loop, you would not gain any headwind at all. You've already been in that wind, moving with it at exactly 20 knots. Your plane might trace a square in the air mass, but would not trace a square visually,- more of a trapezoid.

    You've got to think this through and visualize the plane flying within the moving air mass. You cannot fly "vertically" in this situation at all. Either the plane is pitched up 90 degrees and moving horizontally with the wind OR it is pitched toward the canopy to fight the wind and stay on a true vertical line relative to the ground. In either case, it is not going "vertical" in the way you described.

    You seem to be intent on limiting the description of a square loop to something that is a perfect representation of a geometric shape. I doubt that that has ever been accomplished and my attempts are definitely not perfect. So splitting hairs is silly.
    Larry

  7. #682
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    RE: Downwind turn Myth

    ORIGINAL: BarksKT


    So here is the question of the day??? If you have a load of pelicans in your airplane and you are too heavy to takeoff, if you get them flying in your airplane can you then takeoff?
    Question of the day..........???

    The pelicans support themselves from the air inside the airplane, which suport itself from the plane's walls and wings, which support themselves from the atmosphere, which support itself on the surface of this beautiful planet..........[sm=71_71.gif][sm=72_72.gif][sm=75_75.gif][sm=confused.gif][sm=idea.gif]

    ........which support itself on the back of the Australian pelicans that fly inverted............on the opposite side of the World[sm=drowning.gif][sm=punching.gif]
    Lnewqban - "God will not look you over for medals, degrees or diplomas, but for scars. He has achieved success who has worked well, laughed often, and loved much." - Elbert Hubbard

  8. #683

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    RE: Downwind turn Myth

    Comments in red.
    ORIGINAL: rjbob

    ORIGINAL: flythesky

    Of the 6 people who responded to my square loop scenario all but one did nothing but cry ''YOU CAN'T DO THAT''. And now it's ''I DON'T WANT TO TALK ABOUT IT ANYMORE''. Now that's funny.
    The following is direct quote of your post. I will only make a couple of points here (bold letters).
    For the purposes of discussion, let me start with a square loop. There is a 20kt wind from left to right and I start from the left at 20kts and pull straight up directly iin front of me. I maintain a straight line and slow to 20 kts at the top where I turn into the wind, lose 5 kts and continue at 15 kts plus the added wind speed of 20kt for an air speed of 35kts. In the previous sentence, you just added 15 knots of airspeed to 20 knots of wind and came up with 35 knots of airspeed. The GROUND SPEED would be 35 knots but the airspeed would remain 15 knots. You need to rethink that. The plane is traveling 15kts into a 20kt wind. Think of the 15kts as ground speed. the air speed over the wing is 35kts. I proceed to the down ward turn and dive straight down while chopping the throttle to a speed of 20kts. At the bottom of the leg I pull level, lose 0kts because gravity helped in keeping the speed up in the turn and proceed at 20kts minus the wind speed of 20kts coming from behind for a net air speed of 0kts and hope I can accelerate to a flying air speed before I hit the ground. In the previous sentence, you say your airspeed is 0 knots. Your GROUND SPEED is zero but your airspeed remains 20 knots After diving straight to the ground (by definition straight to the ground would be a ground speed of 0 and making a turn level to the ground, gound speed could not possibly be zero. Reverse the flying direction and I start from the right at 20kts and pull up maintaining a straight line and slow to a speed of 20 kts and at the top I turn with the wind, lose 5kts in the turn and end up at 15kts minus the wind speed of 20kts resulting in an air speed of -5kts Again...your GROUND SPEED is -5 knots (yes the plane looks like it is flying backwards) but your airspeed remains at 15 knots Again your understanding of the scenario is totally wrong. and hope I can gain enough speed on the way down to avoid hitting the ground.

    There...I have tried to spell it out form you. You need to get a piece of paper and draw it out. It doesn't seem like you can visualize what Ihave described.

    If you don't get it by now, you should never fly in the wind without a knowledgeable flyer on the other end of a buddy-box.
    You are definitely in no position ot give advice.
    Larry

  9. #684

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    RE: Downwind turn Myth

    I was referring to my post.

    With my first trainer that would be fun, but Idon't think I'll be flying in a wind that would make it possible with the planes Ihave now.


    ORIGINAL: Tall Paul


    ORIGINAL: flythesky
    ..
    The only thing that would be a legitimate visualization woud be a ground speed of zero as the plane goes straight up or down.

    Not in all cases.
    The wind=takeoff speed takeoffs have zero ground roll.
    Fun to do.
    Watch that first turn, though!
    Larry

  10. #685

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    RE: Downwind turn Myth

    I'll be looking for your input.

    ORIGINAL: FILE IFR

    ORIGINAL: flythesky

    Of the 6 people who responded to my square loop scenario all but one did nothing but cry ''YOU CAN'T DO THAT''. And now it's ''I DON'T WANT TO TALK ABOUT IT ANYMORE''. Now that's funny.
    Larry, if you were to try your experiment just like you describe in your text you'd be surprised you wouldn't "lose (flying) airpseed"..... provided you exhibited good throttle management. It's physically imposible to 'make' the plane do what you want in the description though.


    Try this: Start a thread in the Aerodynamics Forum about this square loop trick.... I'd be surprised to see what others say.

    ... Seriously, start a thread there.
    Larry

  11. #686
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    RE: Downwind turn Myth

    ORIGINAL: flythesky

    Comments in red.
    ORIGINAL: rjbob

    ORIGINAL: flythesky

    Of the 6 people who responded to my square loop scenario all but one did nothing but cry ''YOU CAN'T DO THAT''.Ā* And now it's ''I DON'T WANT TO TALK ABOUT IT ANYMORE''.Ā* Now that's funny.
    The following is direct quote of your post. I will only make a couple of points here (bold letters).
    For the purposes of discussion, let me start with a square loop. There is a 20kt wind from left to right and I start from the left at 20kts and pull straight up directly iin front of me. I maintain a straight line and slow to 20 kts at the top where I turn into the wind, lose 5 kts and continue at 15 kts plus the added wind speed of 20kt for an air speed of 35kts. In the previous sentence, you just added 15 knots of airspeed to 20 knots of wind and came up with 35 knots of airspeed. The GROUND SPEED would be 35 knots but the airspeed would remain 15 knots.Ā* You need to rethink that.Ā* The plane is traveling 15kts into a 20kt wind.Ā* Think of the 15kts as ground speed.Ā* the air speed over the wing is 35kts. Ā* I proceed to the down ward turn and dive straight down while chopping the throttle to a speed of 20kts. At the bottom of the leg I pull level, lose 0kts because gravity helped in keeping the speed up in the turn and proceed at 20kts minus the wind speed of 20kts coming from behind for a net air speed of 0kts and hope I can accelerate to a flying air speed before I hit the ground. In the previous sentence, you say your airspeed is 0 knots. Your GROUND SPEED is zero but your airspeed remains 20 knotsĀ* After diving straight to the ground (by definition straight to the ground would be a ground speed of 0 and making a turn level to the ground, gound speed could not possibly be zero. Ā* Reverse the flying direction and I start from the right at 20kts and pull up maintaining a straight line and slow to a speed of 20 kts and at the top I turn with the wind, lose 5kts in the turn and end up at 15kts minus the wind speed of 20kts resulting in an air speed of -5kts Again...your GROUND SPEED is -5 knots (yes the plane looks like it is flying backwards) but your airspeed remains at 15 knotsĀ* Again your understanding of the scenario is totally wrong. and hope I can gain enough speed on the way down to avoid hitting the ground.

    There...I have tried to spell it out form you.Ā* You need to get a piece of paper and draw it out.Ā* It doesn't seem like you can visualize what IĀ*have described.

    If you don't get it by now, you should never fly in the wind without a knowledgeable flyer on the other end of a buddy-box.
    Ā* You are definitely in no position ot give advice.
    The reason I don't visually realize your description is that it makes no sense.

    I have performed numerous (as in too many to count) loops and square loops in full scale aircraft..and even more in model aircraft. And again, your description makes no sense.
    Alaska Bob - "Can I fly one of your jets? I crashed all of mine."

  12. #687

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    RE: Downwind turn Myth


    ORIGINAL: flythesky


    Comments in red.

    ORIGINAL: RZielin

    In response to FlytheSky's square loop puzzle:

    Sorry Flythesky, not to be condescending, you've made so many oversights and errors that it's kind of comical. You do indeed mix and confuse ground speed with airspeed in your description.Ā* But IĀ*see that you do not describe them. Ā* You also do not define what you mean by ''vertical'' or ''square loop''. Do you mean square loop relative to the ground or square loop relative to the air mass? Ā*
    The common everyday square loop that is seen by an observor.Ā* They are two very different things in wind.

    I'll try to be helpful though. First, please note that you cannot truly turn ''vertical'' in a twenty knot wind. A true square loop is physically impossible in such a wind. You display a lack of experience to say that it is impossible, I do it all the time. You can EITHER pitch the plane up 90 degrees to a vertical pitch orientation, OR you can make the plane ascend vertically over the same patch of ground, BUT YOU CANNOT DO BOTH AT THE SAME TIME IN WIND. It is physically impossible.Ā* If you're tring to say that the plane can not be in aĀ* perfectly vertical orientation and ascend vertically in a wind, who cares, the goal is to have the plane ascend in a vertical line.Ā* In a wind you have to make corrections to fly a geometric shape.Ā* And my plane is in a pretty much vertical orientaion doing such manuvers.

    Option 1, the vertical climb relative to the ground: You'd have to pitch up at just the right angle (greater than 90 degrees) into and against the wind so that the wind would keep you ascending/hovering over the same spot of ground while you gain altitude. Pretty impossible to accomplish, but even if you could hit the angle right, the plane would not appear to be rising vertically like a rocket or a ''normal'' square loop. Again you display your inexperience, it's done all the time. Ā* It would appear to be ascending straight up relative to the ground while being pitched toward the canopy at a significant angle (''alpha'').Ā* You've never flown a plane that is capable of vertical lines have you? Ā* Ā* That's not quite what you intended in your description,Ā* You fail miserably as a mind reader. and not quite the vertical leg of a ''square loop''.Ā* As long as the plane is tracing a vertical line it is. In this scenario, you would gain a bit of headwind at the top when you pitch fully upwind, but not the full twenty knots. Part of that twenty knots was already being imparted to the plane as headwind on the up leg, because the plane was pitched into the wind on the way up.Ā* What you are saying is hardly the case.Ā* And any one familiar with just a decent sport plane would know that.


    This part is irrelevant.Ā* The common sense meaning of my post is intended.
    The only other option compatible with physical reality doesn't quite work for a ''square loop'' either. Option 2, the climb at vertical/90 degree angle of pitch: Simply pitching up at a 90 degree angle would result in the plane being blown downwind as it climbs. In this case, the plane would be pitched straight up (vertically pitched) but would not be ascending straight up over the same patch of ground. It would be moving up at a diagonal relative to the pilot and ground. Therefore when pitching fully upwind at the top of the loop, you would not gain any headwind at all. You've already been in that wind, moving with it at exactly 20 knots. Your plane might trace a square in the air mass, but would not trace a square visually,- more of a trapezoid.

    You've got to think this through and visualize the plane flying within the moving air mass. You cannot fly ''vertically'' in this situation at all. Either the plane is pitched up 90 degrees and moving horizontally with the wind OR it is pitched toward the canopy to fight the wind and stay on a true vertical line relative to the ground. In either case, it is not going ''vertical'' in the way you described.

    You seem to be intent on limiting the description of a square loop to something that is a perfect representation of a geometric shape.Ā* I doubt that that has ever been accomplished and my attempts are definitely not perfect.Ā* So splitting hairs is silly.Ā*
    flythesky, I appreciate your attempt to understand my critique, as I have attempted to understand you. However, it's clear that you are not getting the gist of my points, and we're not communicating, just bickering. Perhaps diagrams would help, but I don't have the skill for that. We'll just have to agree to disagree. I stand by my post. You CANNOT climb vertically in a twenty knot wind without tipping the nose of the plane into the wind. Doesn't matter if you're flying a trainer or a pattern plane or an overpowered 3D plane or the USS Enterprise. At twenty knots, you have to pitch the nose into the wind A LOT to ascend vertically. Experience won't help you break the laws of physics. I wish you well, we can all enjoy our hobby without agreeing!

  13. #688
    Flyfalcons's Avatar
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    RE: Downwind turn Myth

    Sorry Larry, your description is messed up. It simply isn't physically possible to do what you describe. The plane is either flying in a vertical pitch attitude (and with the wind), or it is crabbing (via pitch) into the wind to accomplish a vertical line from a ground reference. You can't just mix them up and expect people to take you seriously.
    Ryan Winslow
    Fly PAU!

  14. #689
    FILE IFR 's Avatar
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    RE: Downwind turn Myth

    I'd post that square loop (un-edited original version) senario in the Pattern Plane section... They do sqaure loops all the time in their routine. They hold competitions in 20 MPH winds too... That being said, you're sure to get an answer.

    .... Hey, they might even learn me sumthin'.
    Mike * Intercepting The Localizer* AMA# 365566
    Bud Nosen C-310 Club #32 * J.P.O. Member 2302

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    RE: Downwind turn Myth

    Everyone that disagrees with the first post please go pick up the book Stick and Rudder and read it before continuing to argue. Thanks! The great thing about this hobby is that you dont have to fully understand it to enjoy it. Just another silly question? Who here believes the elevator makes you go up? Sorry just have to fuel the flames on how airplanes really fly! Thanks, Curtis

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    RE: Downwind turn Myth

    In a square loop the plane is flying in a pattern that describes a square from the viewpoint of an observer. The plane does not have to be straight in orientation to any direction that it is moving and frequently is not. I have not mixed up anything. Responding to your post is difficult to do because you say I said something but fail to quote what I said so it is hard to know what you are talking about.

    ORIGINAL: Flyfalcons

    Sorry Larry, your description is messed up. It simply isn't physically possible to do what you describe. The plane is either flying in a vertical pitch attitude (and with the wind), or it is crabbing (via pitch) into the wind to accomplish a vertical line from a ground reference. You can't just mix them up and expect people to take you seriously.
    Larry

  17. #692
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    RE: Downwind turn Myth

    It's really simple, Larry. If you are flying at 20 knots airspeed in a 20 knot wind, it is not possible to fly a vertical flight path. Period. It's simple Geometry, buddy. If you were smart enough to get to (and pass) junior high geometry, you would understand the vectors do not allow for anything but level flight at 0 knots ground speed. Pull up even slightly and at 20 knots airspeed, the airplane is no longer capable of 0 knots groundspeed.

    Chew on that a bit, would ya?
    Ryan Winslow
    Fly PAU!

  18. #693
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    RE: Downwind turn Myth

    ORIGINAL: flythesky

    In a square loop the plane is flying in a pattern that describes a square from the viewpoint of an observer.Ā* The plane does not have to be straight in orientation to any direction that it is moving and frequently is not.Ā* I have not mixed up anything.Ā* Responding to your post is difficult to do because you say I said something but fail to quote what I said so it is hard to know what you are talking about.Ā*

    ORIGINAL: Flyfalcons

    Sorry Larry, your description is messed up. It simply isn't physically possible to do what you describe. The plane is either flying in a vertical pitch attitude (and with the wind), or it is crabbing (via pitch) into the wind to accomplish a vertical line from a ground reference. You can't just mix them up and expect people to take you seriously.
    This is a direct quote from your scenario:


    ORIGINAL: flythesky

    For the purposes of discussion, let me start with a square loop. There is a 20kt wind from left to right and I start from the left at 20kts and pull straight up directly iin front of me. I maintain a straight line and slow to 20 kts at the top where I turn into the wind, lose 5 kts and continue at 15 kts plus the added wind speed of 20kt for an air speed of 35kts.


    In that sentence, you added 20 knots of wind speed to 15 knots of airspeed and came up with 35 knots of airspeed. That is incorrect...the airspeed will remain at 15 knots regardless of the wind speed.

    And here is another point that I'm certain others have thought of but didn't mention because the absence of logic in your scenario makes this seem less important. Here goes...If an airplane is flying at an airspeed of 20 knots and the wind is 20 knots, it is impossible to complete a square loop. This is because an airplane cannot complete one of the horizontal legs of the square loop as the GROUND SPEED in one of the horizontal legs is ZERO. In other words the plane will go straight up and straight down.

    When the plane is flying with the wind, the ground speed will be 40 knots...against the wind, the ground speed will be ZERO.

    That said, the glaring mistake you make is in the highlighted sentence where you add wind speed to airspeed and come up with a higher total airspeed.
    Alaska Bob - "Can I fly one of your jets? I crashed all of mine."

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    RE: Downwind turn Myth

    If you had taken the physics class you would understand that it is possible.

    ORIGINAL: Flyfalcons

    It's really simple, Larry. If you are flying at 20 knots airspeed in a 20 knot wind, it is not possible to fly a vertical flight path. Period. It's simple Geometry, buddy. If you were smart enough to get to (and pass) junior high geometry, you would understand the vectors do not allow for anything but level flight at 0 knots ground speed. Pull up even slightly and at 20 knots airspeed, the airplane is no longer capable of 0 knots groundspeed.

    Chew on that a bit, would ya?
    Larry

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    RE: Downwind turn Myth

    I'm sorry but it's simply not. If the aircraft has an airspeed of 20 knots, any deviation from perfectly straight and level will result in a groundspeed of less than 20 knots in calm air conditions, correct? I would hope you agree. Now, if that same aircraft travelling 20 knots is flying into a 20 knot direct headwind, you would agree that the groundspeed would be exactly zero. Good so far? Great. So, when that aircraft, flying into a 20 knot headwind with a 20 knot airspeed, deviates in any fashion from straight and level (including pitching up), there is no possible way for that aircraft to overcome the 20 knot headwind and maintain zero groundspeed. Sorry but in this case, most junior high kids are smarter than you. Draw it out with crayons if it makes you feel better. Have a nice day.
    Ryan Winslow
    Fly PAU!

  21. #696
    rcjets_63's Avatar
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    RE: Downwind turn Myth

    ORIGINAL: Lnewqban
    Question of the day..........???

    The pelicans support themselves from the air inside the airplane, which suport itself from the plane's walls and wings, which support themselves from the atmosphere, which support itself on the surface of this beautiful planet..........which support itself on the back of the Australian pelicans that fly inverted............on the opposite side of the World
    What a load of nonsense. The planet is supported on the BELLYS of the Australian pelicans since they fly INVERTED on the opposite side of the world. Holy Newton, anyone with even a passing understanding of relativity knows that!!!!

    Regards,

    Jim
    Jeti USA Flight Team, Kingtech Turbines, bavarianDEMON / DemonAero team, MKS Servos USA, National Vice-President - Jet Pilots Organization, Jet Team USA - JWM 2015
    http://www.espritmodel.com, http://www.kingtechturbines.com, http://www.demonaero.com, http://www.mksservosusa.com, http://www.jetpilots.org, http://www.jwm2015.com/en/start.html

  22. #697
    highhorse's Avatar
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    RE: Downwind turn Myth

    GUYS,

    IGNORE, IGNORE, IGNORE

    "Flythesky"

    He's SCREWING WITH YOU and you are swallowing the bait.
    RCU Rocks, I\'\'d hate to be without it !!

  23. #698

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    RE: Downwind turn Myth


    ORIGINAL: rjbob

    ORIGINAL: flythesky

    In a square loop the plane is flying in a pattern that describes a square from the viewpoint of an observer. The plane does not have to be straight in orientation to any direction that it is moving and frequently is not. I have not mixed up anything. Responding to your post is difficult to do because you say I said something but fail to quote what I said so it is hard to know what you are talking about.

    ORIGINAL: Flyfalcons

    Sorry Larry, your description is messed up. It simply isn't physically possible to do what you describe. The plane is either flying in a vertical pitch attitude (and with the wind), or it is crabbing (via pitch) into the wind to accomplish a vertical line from a ground reference. You can't just mix them up and expect people to take you seriously.
    This is a direct quote from your scenario:


    ORIGINAL: flythesky

    For the purposes of discussion, let me start with a square loop. There is a 20kt wind from left to right and I start from the left at 20kts and pull straight up directly iin front of me. I maintain a straight line and slow to 20 kts at the top where I turn into the wind, lose 5 kts and continue at 15 kts plus the added wind speed of 20kt for an air speed of 35kts.


    In that sentence, you added 20 knots of wind speed to 15 knots of airspeed and came up with 35 knots of airspeed. That is incorrect...the airspeed will remain at 15 knots regardless of the wind speed.
    You fail to realize that the airplanes air speed up is equalivent to a groud speed. It is a distance over time. The air speed and the ground speed are the same in still air are they not? The speed of the plane when it is going up is into still air in relation to the direction of the plane. This speed (a distance over time) of the airplane is then directed into a mass of air that is traveling in the opposite direction at 20kts and results in an air speed over the plane of 35kts. It would have been more precise to describe the motions of the plane as vectors of force but that would have made the description twice as complicated. It doesn't seem to matter now because I spend at least as much time explaining what is happening.

    And here is another point that I'm certain others have thought of but didn't mention because the absence of logic in your scenario makes this seem less important. Here goes...If an airplane is flying at an airspeed of 20 knots and the wind is 20 knots, it is impossible to complete a square loop. This is because an airplane cannot complete one of the horizontal legs of the square loop as the GROUND SPEED in one of the horizontal legs is ZERO. In other words the plane will go straight up and straight down.

    When the plane is flying with the wind, the ground speed will be 40 knots...against the wind, the ground speed will be ZERO.

    That said, the glaring mistake you make is in the highlighted sentence where you add wind speed to airspeed and come up with a higher total airspeed.
    Larry

  24. #699
    rjbob's Avatar
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    RE: Downwind turn Myth


    ORIGINAL: flythesky


    ORIGINAL: rjbob

    ORIGINAL: flythesky

    In a square loop the plane is flying in a pattern that describes a square from the viewpoint of an observer.Ā* The plane does not have to be straight in orientation to any direction that it is moving and frequently is not.Ā* I have not mixed up anything.Ā* Responding to your post is difficult to do because you say I said something but fail to quote what I said so it is hard to know what you are talking about.Ā*

    ORIGINAL: Flyfalcons

    Sorry Larry, your description is messed up. It simply isn't physically possible to do what you describe. The plane is either flying in a vertical pitch attitude (and with the wind), or it is crabbing (via pitch) into the wind to accomplish a vertical line from a ground reference. You can't just mix them up and expect people to take you seriously.
    This is a direct quote from your scenario:


    ORIGINAL: flythesky

    For the purposes of discussion, let me start with a square loop. There is a 20kt wind from left to right and I start from the left at 20kts and pull straight up directly iin front of me. I maintain a straight line and slow to 20 kts at the top where I turn into the wind, lose 5 kts and continue at 15 kts plus the added wind speed of 20kt for an air speed of 35kts.


    In that sentence, you added 20 knots of wind speed to 15 knots of airspeed and came up with 35 knots of airspeed. That is incorrect...the airspeed will remain at 15 knots regardless of the wind speed.
    You fail to realize that the airplanes air speed up is equalivent to a groud speed.Ā* It is a distance over time.Ā* The air speed and the ground speed are the same in still air are they not?Ā* The speed of the plane when it is going up is into still air in relation to the direction of the plane.Ā* This speed (a distance over time) of the airplane is then directed into a mass of air that is traveling in the opposite direction at 20kts and results in an air speed over the plane of 35kts.Ā* It would have been more precise to describe the motions of the plane as vectors of force but that would have made the description twice as complicated.Ā* It doesn't seem to matter now because I spend at least as much time explaining what is happening.Ā* Ā*

    And here is another point that I'm certain others have thought of but didn't mention because the absence of logic in your scenario makes this seem less important. Here goes...If an airplane is flying at an airspeed of 20 knots and the wind is 20 knots, it is impossible to complete a square loop. This is because an airplane cannot complete one of the horizontal legs of the square loop as the GROUND SPEED in one of the horizontal legs is ZERO. In other words the plane will go straight up and straight down.

    When the plane is flying with the wind, the ground speed will be 40 knots...against the wind, the ground speed will be ZERO.

    That said, the glaring mistake you make is in the highlighted sentence where you add wind speed to airspeed and come up with a higher total airspeed.
    You're wrong...really wrong.

    Good bye.
    Alaska Bob - "Can I fly one of your jets? I crashed all of mine."

  25. #700
    rjbob's Avatar
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    RE: Downwind turn Myth


    ORIGINAL: highhorse

    GUYS,

    IGNORE, IGNORE, IGNORE

    ''Flythesky''

    He's SCREWING WITH YOU and you are swallowing the bait.
    So difficult.

    But you're correct.

    Time to ignore...or, at least TRY to ignore.
    Alaska Bob - "Can I fly one of your jets? I crashed all of mine."


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