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AR-1 N923DJ Texas 15-12-18

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  • Loftus, you are right. What you mention is what I teach in strong wind conditions. The increased speed gives more KE. I have not felt a need for any rule of thumb increase. In a practice engine out situation the approach speeds can vary depending on the landing area chosen. One can use any combo of vertical and horizontal speed as well as bank and rudder, as long as the machine limitations are not exceeded. But I always advocate that the last 200 ft of height has to be at or above 60 mph (for the AR1) prior to the flare depending on the wind speed.

    The purpose of the flare is to reduce both the horizontal and vertical velocity and it is during the brief period close to the ground where problems may occur. If the flare is done at a higher speed than normal in calm winds, there can be a slightly increased float period. If the Rate of Flare is high or low, that can affect the rate of sink. So there are many variables close to the ground during the flare. That is the point at which one should be prepared to add some power to smooth things out, or go round if either there is a faster ROD or a ballooning, both of which could occur during wind shears and gusts. Only problem is during an actual situation when the engine goes quiet. The increased forward speed will add a bit to the rudder authority sans prop thrust. During a power on approach and landing, the extra AS should not be an issue IMHO.

    Kolibri, I appreciate your efforts to have a more cordial atmosphere and look forward to a fruitful 2019.
    Antony Thomas
    “Learning without thought is labor lost; and thought without learning is perilous”
    ― Confucius

    Comment


    • Meanwhile, this thorny olive branch showed up in my PM box:
      WaspAir, first of all, there was no "meanwhile" about it.
      I PMed you within a half-hour of your dismissive post #100, as the time stamp shows.
      My olive branch I wrote and posted nearly 7 hours later, after some reflection.

      Also, I would never publicly post a PM sent to me in private.
      I am disappointed that you did, and to falsely imply my insincerity.


      ___________
      Kolibri, I appreciate your efforts to have a more cordial atmosphere and look forward to a fruitful 2019.
      Thank you Antony, likewise!

      Regards,
      Kolibri
      PP - ASEL complex (Piper 180, C206, RV-7A), SP - Gyro (Calidus, RAF, SC2), soloed in gliders

      Wasn't happy with my RAF's pitch instability, so I installed a Boyer H-Stab to my great satisfaction!

      "
      When an honest but mistaken man learns of his error, he either ceases to be mistaken -- or he ceases to be honest."

      Comment


      • Folks, there still lingers an unanswered question, and IMO an important one.

        Where are gusts and wind shear likely to be more severe: within a few feet above the runway, or at 20+ feet?

        Thanks for any comments on this.
        PP - ASEL complex (Piper 180, C206, RV-7A), SP - Gyro (Calidus, RAF, SC2), soloed in gliders

        Wasn't happy with my RAF's pitch instability, so I installed a Boyer H-Stab to my great satisfaction!

        "
        When an honest but mistaken man learns of his error, he either ceases to be mistaken -- or he ceases to be honest."

        Comment


        • Originally posted by loftus View Post
          All bickering and theoretical arguments aside. I am not a CFI, I am a low time pilot with 250 hours in a gyro and about 250 in a FW. My only interest is to be able to be more knowledgeable and safe regarding my future flying experiences and approaches to land, and not to argue theoretical considerations. I tend to fly my approaches to land, even in the gyro at our busy airport (KDED) in a standard pattern, not as thomasant describes his approach in this incident, so I am not concerned here about reverse flow through the blade etc. I find my control inputs and glide slope on approach in an Aircam (High drag fixed wing) are not unlike the gyro except for increased rudder input in the Aircam.
          From a pure practical perspective. Assume I am making an approach to land and winds are moderate to high, say 14, gusting to 22. This wind info is the only thing I can actually have clear information about. I cannot know with any real predictability about wind shear and downdrafts etc, but I can assume that these are more likely under these gusty conditions. My present approach for both gyro and FW is to increase power and airspeed by about half the gust factor. In both cases my ground speed will not generally increase, and will possibly be decreased compared to a low wind day. I am not questioning or asking about how long to fly over the runway, how high and when to round out etc.
          It seems to me that in both the gyro and the FW I am building in an extra reserve of energy and lift to buffer any possible variations in wind speed close to the ground. (A gyro cannot stall, but still comes down pretty hard when behind the power curve). I understand that when in doubt on landing I will still apply full power and go around. Simple question to the CFI's, is there a flaw in this argument and am I doing something in a gyro which is likely to make my landing less safe?
          In my opinion there is nothing wrong or hazardous with carrying more speed on approach in 14kts gusting to 22kts and there is some validity in your adding a little speed to your approach even for a gyroplane Jeffery.

          At the Santa Maria Public Airport (SMX) they don’t switch from runway three zero to runway one two till there is a seven knot tail wind. Runway one two is available on request but it creates challenges for the tower. Because I am touching down at the same air speed with a seven knot tail wind my ground speed is at least seven knots higher. In this condition I add a little extra airspeed for gusts.

          Sometimes I am the last to land on three zero before they turn it around.

          San Luis Obispo has the same procedure but it is a completely different environment. I often use less indicated air speed in gusting conditions.

          In my experience wind can change much more quickly than my twenty second approach to land.

          I do not have a rule of thumb; I add the extra indicated air speed by feel.

          If this was an argument this would support your hypothesis that some extra airspeed is good in gusting conditions. I hope this is not an argument.

          I have not found the benefit in carrying more airspeed in gusting conditions other than in the above exceptions.

          In my experience the ATIS or the ASOS seldom relates to the actual conditions where I land.

          The AWOS can be confusing because it gives the wind in true rather than magnetic. The isogonic lines on your chart will tell you what the variation is.

          My prime source of wind information comes from the wind sock that I am going to land near.

          Most wind socks that I encounter are fifteen knot wind socks. That is to say if they are full erect when the wind is fifteen knots or greater.

          The more I see the wind sock moving around or twitching the more turbulence I prepare for with a little extra power for rudder authority.

          At some airports the tetrahedron is the best source of wind information. Some local knowledge has value here.

          In my experience every landing is different even when just flying the pattern.

          Part of what I do during the approach and the round out is get a feel for the aircraft and how it is responding to my control inputs on that day in those conditions. I like to get a feel for how much pedal pressure will get me the runway alignment I want.

          The Predator descends faster in uncoordinated flight so I want to get a feel for that too if I am going to need rudder to stay aligned with my direction of travel.

          If you are moving outside the winds you are comfortable with I suggest you build up your experience with winds gradually and don’t hesitate to divert if you are not comfortable.

          I have found wind conditions dramatically different just a few miles away.

          Many landing mishaps are on the second or third attempt.

          It is a long answer to a short question because I feel their is value in the basics.
          Regards, Vance Breese Gyroplane CFI http://www.breeseaircraft.com/

          Comment


          • Originally posted by Kolibri View Post
            Folks, there still lingers an unanswered question, and IMO an important one.

            Where are gusts and wind shear likely to be more severe: within a few feet above the runway, or at 20+ feet?

            Thanks for any comments on this.
            In my opinion because the ground doesn't suck and most down drafts are dissipated as you get near the ground you go from three dimensional turbulence a thousand feet above the ground (pattern altitude at most airports) progressively to two dimensional turbulence as you approach the ground.

            There may be higher wind speeds near the ground as a result of it going to two dimensions.

            Ground obstacles or surface features may increase wind shear near the ground.

            In my opinion it is dangerous to fly fast in turbulence near the ground because there is less room for variance when close to something solid you don't want to hit.

            In my experience it is more difficult to fly precisely in strong gusting conditions.
            Regards, Vance Breese Gyroplane CFI http://www.breeseaircraft.com/

            Comment


            • In my opinion because the ground doesn't suck and most down drafts are dissipated as you get near the ground you go from three dimensional turbulence a thousand feet above the ground (pattern altitude at most airports) progressively to two dimensional turbulence as you approach the ground.
              Am I reading you correctly that vertical turbulence turns into horizontal turbulence without having first reached the ground, but merely "as you approach the ground"?
              PP - ASEL complex (Piper 180, C206, RV-7A), SP - Gyro (Calidus, RAF, SC2), soloed in gliders

              Wasn't happy with my RAF's pitch instability, so I installed a Boyer H-Stab to my great satisfaction!

              "
              When an honest but mistaken man learns of his error, he either ceases to be mistaken -- or he ceases to be honest."

              Comment


              • Interesting question actually, and my thoughts:

                Let's imagine a waterfall. What happens as it strikes the bottom? Mostly it spreads sideways. Some of it may splash upwards too. But mostly sideways towards the path of least resistance. Now in the case of water, it is considered incompressible, so it's sideways movement has to occur after it strikes the bottom. But in the case of a descending column of air, it is actually compressible. So I feel it must begin to spread sideways as it approaches the ground, as pressure begins to rise at the bottom, and there is nothing to enclose it. Again, the height is speculative, as there is no way we can measure the column, unless it is studied with smoke. Are there any such studies? IMHO it may be difficult to definitively say at what height the stream goes sideways as air is more compressible than fluids.

                Getting back to how turbulence affects us and if vertical turns into horizontal without reaching the ground, I believe it will be hard to quantify in a particular situation. IMHO, the important thing is how one deals with it at whatever height one encounters it.

                P.S. Am on my second glass of wine, and so....
                Antony Thomas
                “Learning without thought is labor lost; and thought without learning is perilous”
                ― Confucius

                Comment


                • Originally posted by Kolibri View Post
                  Am I reading you correctly that vertical turbulence turns into horizontal turbulence without having first reached the ground, but merely "as you approach the ground"?
                  No you are not Kolibri.

                  The definition I use for turbulence is the rapid change of the speed and or direction of air that I am flying through.

                  As I use the words; descending air is not descending turbulence and there is no vertical or horizontal turbulence.

                  You may be assigning a different meaning to the word turbulence.

                  The ground doesn't suck so the descending air finds somewhere else to go as it nears the ground; not necessarily horizontal and not necessarily turbulent.

                  I have watched collapsing thunderstorms in the Arizona desert and the dust is lowest near the center of the column and gets higher as it moves away from the center indicating to me my that the vertical column of rapidly descending air spreads out in all directions and begins to rise as it gets further away from the column. I don’t deal with collapsing thunderstorms in a gyroplane.

                  If I have a tail wind as I approach a hill at a constant indicated air speed my ground speed on the GPS slows as I near the hill and I encounter an up draft and gain altitude without adding power. It does not happen suddenly as though I was hitting a wall; it happens gradually as I approach the hill. When I reach the leeward side of the hill I often encounter a down draft.

                  In Antony's waterfall example above in post 112; it is my observation if there is nowhere for the falling water to go the water stops falling and becomes a lake and quickly becomes placid.
                  Regards, Vance Breese Gyroplane CFI http://www.breeseaircraft.com/

                  Comment


                  • So I feel it must begin to spread sideways as it approaches the ground, as pressure begins to rise at the bottom, and there is nothing to enclose it.
                    Antony, thanks for the compressability observation, which was helpful.
                    I can see that . . . IF the air has already reached the ground.
                    Then (and not beforehand) it not only spreads out radially, but also begins to (slightly) compress from the ground up.


                    __________
                    Vance, thank you for the clarification.
                    However, distinctions between turbulence and down/updrafts aside, I still find two statements confusing:


                    "most down drafts are dissipated as you get near the ground"
                    In my opinion, that embeds an unnecessary confusion by including the ground.
                    It's like saying, "
                    A ball rolled across the floor loses speed as it approaches a wall."
                    To me, it misconflates correlation as causality, as if the ground has anything to do with enroute energy dissipation. It doesn't.

                    I think what would be more accurate and helpful is simply state, "Unless added to, wind loses energy over distance."
                    While a downdraft is by definition heading toward the ground, the ground itself is moot unless/until the descending air reaches it.
                    I.e., why mention the ground at all unless it's relevant?

                    Your tailwind example of approaching a hill and feeling the updraft and then leeward downdraft actually goes to the point I am making.
                    That related air was in contact with the surface, and reacting to it. However, at, say, 2000 AGL, you may not notice it at all because it's lost its energy by then.


                    "progressively to two dimensional turbulence as you approach the ground"
                    What I was trying to ask about was whether in your opinion descending air can spread out laterally/horizontally without any of it having already reached the ground.
                    I so far cannot see how such could be possible.

                    Regards,
                    Kolibri

                    PP - ASEL complex (Piper 180, C206, RV-7A), SP - Gyro (Calidus, RAF, SC2), soloed in gliders

                    Wasn't happy with my RAF's pitch instability, so I installed a Boyer H-Stab to my great satisfaction!

                    "
                    When an honest but mistaken man learns of his error, he either ceases to be mistaken -- or he ceases to be honest."

                    Comment


                    • I think this is all just different people saying the same thing in different ways. When a downdraft, or it's big brother, a microburst, hit the ground, the wind direction of the downdraft switches from vertical to horizontal, and can even have a cushioning effect, so the vertical component effectively dissipates or goes away and the horizontal component will change in magnitude as it becomes additive or subtractive with the prevailing wind. So the downward effect on the aircraft will effectively dissipate or be non-existent close to the surface, but the horizontal effect on the aircraft will change I imagine in a variable and probably unpredictable fashion. Really just a matter of changing vectors. Lots of this to read about on the internet, but it's a well described phenomenon particularly with the stages of microburst development as they approach the ground. My conclusion from all this is that one cannot really know in these conditions what effect the air movement vectors (magnitude and direction of the wind and downdraft combination) will have on the aircraft close to the surface, therefore increase my power and airspeed to build in an energy buffer on approach to minimize any effects as much as possible. Thanks all for this great discussion.
                      https://www.weather.gov/bmx/outreach_microbursts
                      https://en.wikipedia.org/wiki/Microburst

                      Comment


                      • True, loftus, but remember that we're mostly talking about moderate downdrafts vs. extreme ones.
                        And, I thought it important to clarify the notion that horizontal transference requires the descending column of air to have first hit the ground.
                        Vance many times has written that
                        "downdrafts don't (or don't usually) reach the ground" and I disagreed with that as a blanket statement.
                        Rather, I think they often reach the ground.


                        A tautology of "downdrafts don't reach the ground, unless they do" doesn't seem very helpful.

                        PP - ASEL complex (Piper 180, C206, RV-7A), SP - Gyro (Calidus, RAF, SC2), soloed in gliders

                        Wasn't happy with my RAF's pitch instability, so I installed a Boyer H-Stab to my great satisfaction!

                        "
                        When an honest but mistaken man learns of his error, he either ceases to be mistaken -- or he ceases to be honest."

                        Comment


                        • Originally posted by Kolibri View Post

                          __________
                          Vance, thank you for the clarification.
                          However, distinctions between turbulence and down/updrafts aside, I still find two statements confusing:[/COLOR]

                          "most down drafts are dissipated as you get near the ground"
                          In my opinion, that embeds an unnecessary confusion by including the ground.
                          It's like saying, "
                          A ball rolled across the floor loses speed as it approaches a wall."
                          To me, it misconflates correlation as causality, as if the ground has anything to do with enroute energy dissipation. It doesn't.

                          I think what would be more accurate and helpful is simply state, "Unless added to, wind loses energy over distance."
                          While a downdraft is by definition heading toward the ground, the ground itself is moot unless/until the descending air reaches it.
                          I.e., why mention the ground at all unless it's relevant?

                          Regards,
                          Kolibri
                          Originally posted by Kolibri View Post
                          Folks, there still lingers an unanswered question, and IMO an important one.

                          Where are gusts and wind shear likely to be more severe: within a few feet above the runway, or at 20+ feet?

                          Thanks for any comments on this.
                          I included the reference to the ground because your question was about gusts and wind shear near the runway.

                          I don't know how to make my response less confusing to you.

                          You frame of reference and focus seem sufficiently divergent from mine to make communication difficult.

                          I am trying to describe turbulence in the way it relates to flying a gyroplane based on my experience flying in turbulence.

                          I have a Gleim publication that you might find helpful: Aviation Weather and Weather Services by Irvin N. Gleim.

                          Chapter Nine is on turbulence and it may aid in resolving your confusion.

                          It is not a simple subject with simple answers.

                          Regards, Vance Breese Gyroplane CFI http://www.breeseaircraft.com/

                          Comment


                          • Originally posted by Kolibri View Post
                            True, loftus, but remember that we're mostly talking about moderate downdrafts vs. extreme ones.
                            And, I thought it important to clarify the notion that horizontal transference requires the descending column of air to have first hit the ground.
                            Vance many times has written that
                            "downdrafts don't (or don't usually) reach the ground" and I disagreed with that as a blanket statement.
                            Rather, I think they often reach the ground.


                            A tautology of "downdrafts don't reach the ground, unless they do" doesn't seem very helpful.
                            It appears to me you want to have a semantics debate on what the boundaries of a down draft are.

                            In my usage from a practical perspective; the down draft ends when it does not have sufficient velocity to cause my gyroplane to descend. This is generally well above the ground.

                            The last time I looked the air was touching the runway from end to end at SMX.

                            The history of a particular molecule of air is not relevant to my flying.

                            The effect its present movement has on my gyroplane is relevant to my flying.



                            Regards, Vance Breese Gyroplane CFI http://www.breeseaircraft.com/

                            Comment


                            • I don't know how to make my response less confusing to you.
                              This would help: disavow any inference that a descending column of air can make 90 degree radial turns above ground without having first hit the ground.

                              Such would clarify a proper mental picture, thank you.


                              PP - ASEL complex (Piper 180, C206, RV-7A), SP - Gyro (Calidus, RAF, SC2), soloed in gliders

                              Wasn't happy with my RAF's pitch instability, so I installed a Boyer H-Stab to my great satisfaction!

                              "
                              When an honest but mistaken man learns of his error, he either ceases to be mistaken -- or he ceases to be honest."

                              Comment


                              • the down draft ends when it does not have sufficient velocity to cause my gyroplane to descend.
                                Agreed.

                                This is generally well above the ground.
                                Then there's little risk from downdrafts when flying low to the ground.

                                And when a downdraft does reach the ground, I'd rather be lower to minimize any vertical drop impact, with some horizontal speed to spread it out.
                                This is essentially what I've been trying to express throughout this thread.

                                ____
                                When there is horizontal wind shear, rotors from trees and hangars, variable gusts, etc. be prepared to go around.
                                I like go arounds. As one CFI used to tell me, "
                                Never expect to land, but always expect to go around."
                                With a flatter and slightly faster pre-flare flight path, I find going around easier.
                                I've already good AS to add to, and I do so within ground effect as I build up to Vx or Vy.

                                But folks are free to fly as they wish. Thanks for everyone's input.

                                Regards,
                                Kolibri
                                PP - ASEL complex (Piper 180, C206, RV-7A), SP - Gyro (Calidus, RAF, SC2), soloed in gliders

                                Wasn't happy with my RAF's pitch instability, so I installed a Boyer H-Stab to my great satisfaction!

                                "
                                When an honest but mistaken man learns of his error, he either ceases to be mistaken -- or he ceases to be honest."

                                Comment

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