Tri-Mower Design

Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by blane.c, Jan 23, 2020.

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  1. Jan 27, 2020 #61

    blane.c

    blane.c

    blane.c

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    The thing is also it may just be easier to find an ATP rated pilot or a multi flight instructor that is willing to fly your plane. Then you are just paying them to solo you so you can practice. I believe there are provisions that the instructor doesn't have to be in the plane for certain circumstances they just observe. Getting a multi engine endorsement? Basically. To your private pilot certificate. The FAA may be able to sign you off to fly "YOUR multi-engine plane only" some how also. Some letter of authorization or waiver. Just spitballing but I bet there is a solution to this that is acceptable to all party's.
     
  2. Jan 27, 2020 #62

    blane.c

    blane.c

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    Yes ... and you can flip over a single engine high performance airplane if you don't know what you are doing also. Many of the WW2 types and I am sure others as well. That requires a high performance sign off (over 200hp).
     
  3. Jan 27, 2020 #63

    blane.c

    blane.c

    blane.c

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    Get in a Hellcat cob in the power of that R-2800 and see which way the world spins.
     
  4. Jan 27, 2020 #64

    blane.c

    blane.c

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    Correction.
    It is 12" from the center of the fuselage which is 24" wide so 36" from center of the plane to the center of the propeller.
     
  5. Jan 28, 2020 #65

    jedi

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    Register as a motor glider. No multi engine certificate required. Glider certificate with self launch endorsement will do. Climb on three engines. Maintain on two engines. 40:1 glide on one engine. Primary glider performance with no engines. A great glider trainer and could possibly be considered a Light Sport Glider.
     
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  6. Jan 28, 2020 #66

    blane.c

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    There are rules about wing length/weight ratio. So no stubby wings gotta be long proportionally to weight. So if you are trying to get sub 30ft wing span but weight makes you have 40ft wingspan it provides a new set of choices.

    Also I am not sure if you can still have a multi engine glider/sailplane/motor-glider, I am sure you used to be able to.
     
  7. Jan 28, 2020 #67

    jedi

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    "There are [European] rules about wing length/weight ratio. USA rules allow primary type gliders. The US glider rules are still around from the 20s. For experimentals there are even more options. There is a twin jet high performance motor glider in operation in the US. Multiengine motor gliders make sense for the reasons given previously. High relative power required for takeoff and climb. Much lower power required for normal flight. For jet fuel consumption rates the multi engine construction, single engine operation is a large part of the design concept.

    There is no need for US EABs to conform to JAR certification requirements. The same can be said for ASTM Light Sport certifications.
     
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  8. Jan 28, 2020 #68

    BBerson

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    Interesting. I guess you are saying a glider certificate doesn't have any added class ratings at all.
    So Burt's Ski-gull could be flown without a seaplane rating since it's a motorglider.

    I don't know if a Cri-Cri can be certificated as a powered glider. It just depends on the individual FAA/DAR inspector. I don't think any glider definition rules apply to EA-B, but that is up to the DAR.
     
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  9. Jan 28, 2020 #69

    jedi

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    True. the same for a gyroplane. Weight shift Control and powered parachute have land and sea ratings.

    Sea Era operating limitations are about 5 years old and have no provision to require a sea rating. Only two of the five pilots that have flown it have a sea rating.
     
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  10. Jan 28, 2020 #70

    lr27

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    If asymmetrical thrust is a worry, you could make one of the outboard engines flywheel drive and the other pto drive. Them you've either made things a little better or a little worse. ;-)

    P.S. Put a counter-rotating drive on the middle engine.
     
  11. Jan 28, 2020 #71

    jedi

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    A pusher is automatically opposite rotation from a tractor.
     
  12. Jan 29, 2020 #72

    blane.c

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    http://edburkhead.com/Challenger/glider/motorglider1.htm

    http://edburkhead.com/Challenger/glider/Chucks_complaint_ltr.htm

    http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/0/4db2c5cd655cb3cc86257647004af4ee/$FILE/AC 20-27G.pdf

    http://edburkhead.com/Challenger/glider/Airworthiness_QuickSilver_MX_Glider.jpg

    http://edburkhead.com/Challenger/glider/Chucks_Repairman_Certificate.jpg
     
    Last edited: Jan 29, 2020
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  13. Jan 29, 2020 #73

    blane.c

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    I am not worried.
     
  14. Jan 29, 2020 #74

    jedi

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    Most EAB airworthiness certificates do not indicate the category of the aircraft. It is not necessary for the airworthiness certificate to indicate glider for the aircraft to be a glider according to my FAA contact. I was told there is some (nebulous) place in the paperwork where a category can be specified but I do not see a section in the 8130-6 where that information would be appropriate or necessary.
     
  15. Jan 29, 2020 #75

    blane.c

    blane.c

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    I have seen the place, several times. I can't remember were to find it at the moment.

    Here it is found it through Xenos.

    https://www.faa.gov/documentLibrary/media/Form/AC8050-88.pdf
     
    Last edited: Jan 29, 2020
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  16. Jan 29, 2020 #76
  17. Jan 29, 2020 #77

    blane.c

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    BEFORE YOU BUILD YOUR OWN AIRCRAFT

    BEFOR YOU BUILD YOUR OWN AIRCRAFT.png
     
  18. Jan 29, 2020 #78

    BBerson

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    These is blank space next to special airworthiness certificate (line B, section II)
    http://www.faa-aircraft-certification.com/support-files/faaform8130-6.pdf

    Seems appropriate but not required.
     
  19. Jan 29, 2020 #79

    jedi

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    Thanks, I have been wondering about that for a long time.

    Some times it is very difficult for the pilot to know what category of aircraft he is flying. I considered purchasing a Katana years ago. It took the FAA two weeks to answer the question as to whether it was an airplane or motorglider. Airworthiness certificate, Type Certificate Data Sheet, general consensus and owners manual did not agree.

    Finally the FAA inspector said he does not care, either glider pilot or airplane pilot could fly it as far as he was concerned. That answer sounded nice but I wondered if it would hold up in court.

    If I remember correctly it looked like a glider and was a glider (per FAA two week investigation based on the original TCDS) but the airworthiness certificate and owners manual indicated airplane. The owner was selling because he did not want to fly a glider. I suppose he thought he purchased an airplane but did not like the way it flew. One of those with more money than whatever.

    As I indicated earlier if you don't want to fight them confuse em. It works!
     
    Last edited: Jan 29, 2020
  20. Jan 29, 2020 #80

    blane.c

    blane.c

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    Arguing with the FAA is like wrestling with a pig, you are both going to get poopy and you'll find the pig likes it.
     

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