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  • No pop up take off technique

    Saw this youtube video by a UK instructor demonstrating a different takeoff technique. He argues that the full aft stick, which causes the nose to pop up, can overwhelm the pilot by having to mitigate all the bad things that can follow. He prescribes not using full aft stick so the nose never pops up and just lifts off into flight. It's basically trading high drag max angle of attack with less drag lower AOA which means more speed and more air through the blades all without the pop up, not to mention balancing on the mains and staying low after lifting off until climb speed is reached.

    With all the take off accidents this seems like a simpler approach. I'm not a gyro pilot but it sounds good to me. I love to hear other opinions.

    https://youtu.be/QJPgQQtLF7w

  • #2
    Keeping the nose wheel on the ground will cause you to have a lower angle of attack on the rotor blades and will

    take forever to get off the ground. What I did to solve the problem is to move my main gear back so there is more weight on the

    nose wheel,then I can achieve a higher angle of attack with the rotor blades and have a really short takeoff run with the nose wheel

    still on the pavement for positive control.

    I now have a new prerotater housing and flex shaft and can bring my rotor up to 220 rrpm and my ground run is even shorter than before.
    Best Regards,
    Eddie Sigman,Polvadera,nm
    (575) 835-4921

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    • #3
      I recommend following the Pilot’s Operating Handbook.

      None of the POHs I have read recommend this technique.

      I recently had a client keep the nose of The Predator on the ground as he opened the throttle at 200 rotor rpm and he flapped the blades. I took the controls and got the cyclic forward and pulled power before any damage was done.

      The braking of the aft rotor disk keeps most gyroplanes from outrunning the acceleration of the rotor blades.

      Most of my flying is done on hard surfaces.

      For a grass field in poor condition (long wet grass) an early lift off can have value. I would still not do it as recommended in the video.
      Regards, Vance Breese Gyroplane CFI http://www.breeseaircraft.com/

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      • #4
        That is essentially the same technique that Ed Alderfer and then Joe Swanson taught me on their machines. Basically flying them off In a level attitude.
        David McCutchen
        615-390-2228
        Bensen B7m, 90 hp Mac
        Dominator Tandem, 100 hp Hirth
        Kolb Mark III Classic, 80 hp Verner
        Certified - Advanced Master Beef Producer
        EAA Member #0511805
        PRA Member #28866
        PRA Chapter 16 Member
        Secretary & Treasure - PRA Chapter 16
        President / Sylvia - Yellow Creek Volunteer Fire Dept.
        Chairmen - Dickson County Veteran's Day Committee
        Volunteer - Dickson County Airport Aviation Day Committee
        2 busy 2 No!

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        • #5
          Originally posted by Gyro28866 View Post
          That is essentially the same technique that Ed Alderfer and then Joe Swanson taught me on their machines. Basically flying them off In a level attitude.
          Not to hijack the thread, but those 2 names bring back wonderful memories... I have flown with both of them. Ed at Brookville, Ohio convention in the 90s and Joe at Mentone around '04.

          Comment


          • #6
            Here is another video from the same instructor comparing the two take techniques. It's a combination of full aft stick and throttle and once rotor rpm starts increasing the stick is moved forward "one fist" and full throttle slowly applied. He certainly makes a good argument against the pop up wheel balance technique.

            https://youtu.be/kW65IY39MPU

            John

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            • #7
              In my opinion his description and execution of the "wheel balance technique" is very different than what I have seen in the Pilot's Operating Handbook for the AutoGyro MTO Sport.

              His technique is also not by the POH.

              I recommend following the POH for your aircraft.

              In my experience taking off with the "wheel balance technique" will have the aircraft lifting off very close to the desired climb out speed.

              From the POH for the MTO Sport UK edition:
              "START AND CLIMB If possible always take off into wind, and ensure CHT and oil temp at least 50degC. The maximum cross-wind component for take off is 22kts. Set the roll trim, if fitted, to fully left. Switch the pneumatics switch to ‘TRIM’, which releases the rotor brake. Keep the engine at about 2000rpm, and the control stick forward. Disengage the parking brake lock pawl, and hold brakes on by squeezing throttle and brake lever together. Actuate the pre rotator by pressing the button, and as rotor speed increases, increase engine speed to suit. Normal pre spin is a rotor speed of 200 rpm (maximum Prerotator speed is 270 rpm). If the rotor speed overtakes the pre rotator, and the pre rotator disengages, release button. Increase engine rpm and re engage. Disengage pre rotator and pull the stick fully back. Check/adjust trim pressure to about 2bar or less if lightly loaded to reduce stick load on take off Let go brakes, and bring the engine up to take off power. Hold direction using the rudder, and as soon as the nose gear wheel takes off, keep the nose down to build up airspeed and take off in a flat attitude. If necessary reduce stick force by actuating the trim. The best climb speed is 65mph. After reaching your chosen altitude (eg 500ft or circuit height), throttle back to level flight rpm, as required for your chosen airspeed. Pay attention in hot weather to the cylinder head and oil temperatures. If these should rise with long climbs over the placarded values, then adjust your speed or attitude to compensate."
              Regards, Vance Breese Gyroplane CFI http://www.breeseaircraft.com/

              Comment


              • #8
                The "wheel balance technique" arose in part because early gyros had no rotor tachs. A gradual takeoff made certain that RRPM was adequate. Some gyros will take off and fly -- hammering the stops -- with substandard RRPM. This requires an immediate landing which can easily go very poorly.

                The technique also came about because of the rather extreme torque-yawing tendency of the Bensen (and other short-vertical-tail gyros). During the "balancing" phase, the pilot sorts out his rudder input so that he doesn't leave the ground at a radical crab angle. Many, many beginner wrecks have been caused by leaving the ground suddenly, in a crab, and then lighting down misaligned with the direction of travel, resulting in a rollover.

                Helicopter Ed taught me to keep the Wunderlich prerotator engaged throughout the takeoff roll (until it dropped out on its own) , which helps build RRPM quickly. This technique does add to the yawing tendency, though, so it's best to save it 'til your takeoffs have become reliably orderly.

                Some prerotators aren't designed to withstand the "keep it engaged" technique -- which (in my opinion) is a pity.

                Comment


                • #9
                  Ed and Joe both had you use the prerotor, stick forward disk as level as possible, to an rrpm of maybe 125. You learned to look at the disk and judge its rpm. You disengaged the prerotor and applied rear stick and barely moving forward, as not to over feed the rotor and cause the blade flapping to hit the stops. Once at full rear stick, apply a bit more power and watch the rotor rpm and allow it to catch up. As it speeds up apply even more power and continue flying the rotor up to speed. Once the flickering blade becomes a blur, you could go to full power and neutralize the stick pressure. Once the machine is at flight speed it simply lifts off. If the engine was to quit at this moment (been there done that) you have enough airspeed and rotor rpm to safely land under full control. However, if you have just popped it off at a slightly less RRPM and the engine goes quite. You are set up for an immediate drop back on the mains and likely dropping the nosewheel in hard. A hard coupled steerable nose at an angle results in a roll over. I would only recommend a higher time "Gyro" Pilot which knows the machine takeoff this way. I would call it a "Soft field takeoff technique". I routinely takeoff like this, however, as the nosewheel starts to lift, I am going stick forward and stopping the gyro from climbing. I only allow it to lift off to within a couple feet of the runway. I keep her at this very low altitude and allow the engine thrust to accelerate me to about 65 mph before I allow her to start a climb. Rotor rpm is slightly higher also, compared to the lower airspeeds. Stack the deck in your favor, any chance you get. You only have a specific amount of energy to dispense, use the combination of it wisely.
                  David McCutchen
                  615-390-2228
                  Bensen B7m, 90 hp Mac
                  Dominator Tandem, 100 hp Hirth
                  Kolb Mark III Classic, 80 hp Verner
                  Certified - Advanced Master Beef Producer
                  EAA Member #0511805
                  PRA Member #28866
                  PRA Chapter 16 Member
                  Secretary & Treasure - PRA Chapter 16
                  President / Sylvia - Yellow Creek Volunteer Fire Dept.
                  Chairmen - Dickson County Veteran's Day Committee
                  Volunteer - Dickson County Airport Aviation Day Committee
                  2 busy 2 No!

                  Comment


                  • #10
                    I try to use a combination of the 2 techniques, prerotater to about 75% of what the prerotater will do, and start my roll, get my blades up to speed and wait for the airframe to rotate back. Now push the stick forward till the front tire touches back down, not planted on the ground and not ridding on the rear wheel, just lightly touching the ground with the front tire and go WOT. Take off is level and under control. I can see problems with both techniques and think a combination of the 2 is the best way to go. This works well with my KB2
                    David Bacon

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