Part 103 Corsair - carbon tube truss

Discussion in 'The light stuff area' started by bmcj, Dec 1, 2019.

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  1. Dec 1, 2019 #1

    bmcj

    bmcj

    bmcj

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    samyguy and delta like this.
  2. Dec 6, 2019 #2

    Richard6

    Richard6

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    Hum, I'ed be a little concerned about all carbon fiber tubes. Typically they are rather fragile and do not bend, but break.

    Even the slightest rough landing could cause some damage to the structure.

    Richard
     
  3. Dec 6, 2019 #3

    Topaz

    Topaz

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    Parts (structural ones) that have bent on a "real" airplane have been pushed past their yield limit and are just as damaged and in need of replacement. A carbon-tube structure shouldn't "break" if it was designed for the proper loading limits, including "rough" landings.

    I think the far, far, bigger concern for me on this "Part 103 Corsair" is the bad precedent it sets. The "unwritten agreement" with the FAA is that if it looks like an ultralight, flies like an ultralight, and meets the spirit of Part 103, they won't "ramp check" every ultralight that comes along. When people started games with "fat" ultralights and with the two-seat "training exemption," the FAA clamped down and now the Part 103 community doesn't really even have a viable pilot training solution anymore. The scuttlebut has always been that, when pressed about increasing weight and performance limits in Part 103, the back-channel response from the FAA has been, "sure, we can take a close look at Part 103 again - but you won't like what you get in the end."

    As neat as this project is, it strikes me a lot as "poking the bear." YMMV, of course.
     
  4. Dec 7, 2019 #4

    Voidhawk9

    Voidhawk9

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    This sort of thing is causing quite a mess over here in NZ right now in the microlight category. Many of the increasingly popular models can run rings around similar certified types, and it is making the current rules (and more importantly their interpretation and application) quite absurd.
    Sooner or later, there is going to need to be a reconsideration of the rules and requirements of rule parts on both sides of the line.
    What the end results look like will probably depend on who is at the top of the decision-making process (ie a career politician covering themselves or someone with real experience wanting to advance aviation) and who makes the first move.
     
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  5. Dec 7, 2019 #5

    BBerson

    BBerson

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    It looks like it would easily exceed the 55 knot speed limit. I recently read an 1983 archive where the FAA said they could possibly accept a redline on the airspeed or tach indicator. That would not be asking for an airspeed performance rule change, yet allows a safe climb rate with extra power for climb only.
    I think this is standard practice for the Light Sport Carbon Cub.
     
  6. Dec 7, 2019 #6

    Topaz

    Topaz

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    AC103-7 explicitly states that a "redline" on the airspeed indicator is not sufficient to meet the requirements of Part 103. The aircraft must be incapable of exceeding Part 103 maximum-speed-in-level-flight speed. An airspeed indicator marking is specifically called out as insufficient.
     
  7. Dec 7, 2019 #7

    BBerson

    BBerson

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    Yeah, there is considerable discussion in the 1984 Advisory Circular. I was referring to specific comments by Jack Cox in 1983 before that AC was written.
     

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