Search results

  1. P

    Fuel line system

    Remember that a diaphragm failure of a pulse type pump will allow fuel to be pumped into the engine crank case by an electric pump on the same line so it needs to be able to be isolated if needed to continue the flight.
  2. P

    No More Dragon Wings?

    The blade business has been sold but the dominator line of gyros are still being produced at the RFD factory.
  3. P

    My 1970s helicopter

    Chuck, back when I started experimenting with rotors I had never seen a two blade machine up close but I had seem three bladed machines and I did know that they had a hinge that allowed them to flap or cone, I built a rotor on a fixed test stand that only had the flap hinge and would it up in a...
  4. P

    Rotor does not take up speed

    If the rotor is level it won’t speed up, the correct way is to prerotate by hand and start tilting the rotor back before you start moving, if there is even a light breeze it will accelerate quickly but it’s important to have the rotor full back and turning as fast as you can get it before you...
  5. P

    bensen rotor head main bolt size

    I don’t remember that plastic cover, most of the heads that I have seen had a black steel washer that is very important as it keeps the bearing from sliding up over the aluminum center piece leaving you to find your way to the planets surface without a rotor, you will still reach the surface but...
  6. P

    Gyro-tech carbon fiber blades/RAF

    I personally don’t like bearings in the block and I will never use a ball bearing or any bearing with a cage that keep the balls or rollers in place, I used it on a machine for a while and had a cage break apart during spin up that resulted in blades going about two feet out of track, teeter...
  7. P

    My 1970s helicopter

    The only reason I think something happened to your engine to cause this other than being mounted vertically is that these engines and others that are similar ran hundreds of hours in hovercraft mounted vertically without having a problem.
  8. P

    Aviomania Genesis G1sE Sport

    Something that many overlook or don’t seem to understand is that many gyros are not built for maximum efficiency so they need a larger engine , a gyro with a 60 inch prop is not going to perform well on fifty hp and will nearly fly on 40 hp, if you build your machine to swing a 72 or larger it...
  9. P

    Gyro Boat

    Due to the weight of the rotor, head and engine all gyro boats need out riggers, in my first one I put them on a beam across the middle of the boat but later machines had them on the tip of the horizontal stabilizer, the last one that I built was 16 feet and the stabilizer was 12 feet wide so it...
  10. P

    Gyro Boat

    Bensens gyro boat was a glider, actually more of a kit was it needed the towline to be stable a correctly designed gyro boat needs to follow all of the rules of a stable wheel equipped gyro but due to the extra weight they can’t carry as much for a given horsepower and rotor size, they are not...
  11. P


    My original bensen had 1/16 cluster plates, I later replaced them with 1/8 due to cracking, the cracking was caused by rough snow and ice conditions while taxi to a takeoff point and not from in flight loads, the bensen had no suspension other than air in the tires and on skis it didn’t have that.
  12. P

    AG-1 - Las Vegas - N15LU

    Every gyro that I have built has at least 10 inches of clearance between the rotor and tail with the stick full back and the teeter full back, this is the least that you can get away with in real world rough field conditions, years ago I did testing with a light bulb mounted on the tail and with...
  13. P

    Nightmare at El Mirage

    There is nothing wrong with self training as long as it’s done correctly, it is extremely important to get lots of time in the glider and I don’t mean just flying straight down a runway, the conditions you describ would be great for your final few hours of glider time teathered to something...
  14. P

    Coaxial Autogyro

    A machine built this way as a gyro would have very few advantages and lots on disadvantages, the only thing it can do that would improve a normal gyro is the ability to leave the rotor powered as long as you want to , it would be a slower high drag machine.
  15. P

    RAF Rotor Blades

    Were raf blades originally designed as a helicopter blade and then used on a gyro? The reason I ask is that it has more pitch at the root than the tip, it should be the other way for a gyro as the airflow is up through the rotor instead of down like a helicopter.
  16. P

    Who is the best to help me with a propeller

    A 66 inch prop is to short for a 3 to 1 gear box, 70 or 72 would be much better, you are not getting the best that you can from that engine, that type engine and others in its family, 583, 500 , 670, 800 and 1000 really needs a variable pitch prop to have the best performance in all conditions...
  17. P

    Ignition damping box

    I always wondered why rotax put that critter in there as cuyuna JLO, BSE and other engines with the Bosch energy transfer ignition system didn’t have it. I have run many hours without the box there without a problem. norm
  18. P

    Mac 90 crankcase

    The instructions from bensen was to not use the original fuel pump but never said why but I guess it was short life of those pumps.
  19. P

    Mac 90 crankcase

    The instructions from bensen was to not use the original fuel pump but never said why but I guess it was short life of those pumps.
  20. P

    Mac 90 crankcase

    To be accurate a crank case scavenged two stroke crankcase is under pressure when the piston is on the power stroke but pulls a partial vacuum on the compression stroke, original bensen machines used a pressurized fuel system just like older evinrude outboards did, they used the outboard tank...