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tetra t4 homemade ultralight aircraft

55.6k PapaKernels  3.3 years ago
Auto Credit Based on Chrisk1993's Homemade Challenge : Build a DiY Airplane!

this is the tetra t4 for the homemade aircraft challenge!!

history

The Tetra t4 was a 25hp, ultralight like aircraft created by Mark Tetra in the mid 1980s. It featured a homemade engine that he took from a motorcycle, and built the frame up around it. The plane is mainly made out of lightweight steel tubes and plywood, with most of the structure made out of high quality steel tubing. The wings are a simple canvas over wood, and the cockpit is made up of misalanis items from different types of aircraft, with the seat being a lawn chair duck taped in the back, and bolted in the front. Over the 2 years of its existence, Mark had to change out some parts that got broken or needed replacing, and just never painted them, that's why some parts of the plane are still in a metallic color. The main complaint was the short roof and was eventually the whole aircraft was scraped for a whole different design, which was later given to Taikav Areo Industries, which they made into the T16.

engine (haven't done this in awhile)

1 25hp pp55, nicknamed the Pipsy

performance

topspeed: around 105mph
takeoff speed: around 61 all due to the rear gear placement
stall speed: around 30
service ceiling: N/A

controls

Normal flight controls
No special controls

fetures

Fully moveable rudder
Working control surfaces on the horizontal stabilizer and main wings
A mostly detailed interior, complete with control stick, dials, and precariously put lawn chair
A pretty well modeled engine, complete with fuel lines, and the intake manifold


gallery




That just looks beautiful dont it?


Builders note: this is a very fun aircraft to fly, flight is a bit wonky but that's what makes it fun. Yaw can be a bit aggressive so go in slow and release slow. I tried making the engine look good, and I think I succeeded, it looks very nice for being on of the firsts in have done. It can tip over on landing just a warning.

thanks to those who upvote, comment, and follow

papakernels 1/29/2021 (a whole month has almost gone by already?!)

General Characteristics

Performance

  • Horse Power/Weight Ratio 0.065
  • Wing Loading 6.0lbs/ft2 (29.3kg/m2)
  • Wing Area 63.9ft2 (5.9m2)
  • Drag Points 191

Parts

  • Number of Parts 143
  • Control Surfaces 4
  • Performance Cost 551
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  • Profile image
    55.6k PapaKernels

    Now that I look at the thumbnail, I get some mild cessna vibes, am I the only one?

    Pinned 3.3 years ago
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    55.6k PapaKernels

    Sorry I haven't posted in nearly 2 weeks, I've been pretty busy with alot of projects I've been playing with

    Pinned 3.3 years ago
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    3,214 Chrisk1993

    @UltraLight I just want to address the point you made about weight, idk if others do but when I'm building such a light craft I like to add about 250 lbs (I'm fat) in the location of the pilots seat. And keep the fuel weight as realistic as possible. I feel like otherwise I'm just building really big RC plane. With things this small I think it's important to simulate the load.

    3.3 years ago
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    55.6k PapaKernels

    @Musraskrois thanks! Glad I'm not the only one.

    3.3 years ago
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    55.6k PapaKernels

    @UltraLight ok I wasn't sure how I could move the rear gear to make the takeoff speed more, that's the one thing I knew I did wrong and wanted to fix. Thanks for the criticism, I kinda thought that's what you would say, I will definitely work on that for my next ultralight!

    3.3 years ago
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    18.6k Kroixo

    Very nice build. Love the whole backstory behind the plane. And ur right it cinda looks like a Cessna in the tumbnail

    3.3 years ago
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    41.7k rexzion

    @UltraLight re

    3.3 years ago
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    38.3k UltraLight

    @rexzion because

    3.3 years ago
  • Profile image
    41.7k rexzion

    @UltraLight why

    3.3 years ago
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    38.3k UltraLight

    @rexzion I did

    3.3 years ago
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    41.7k rexzion

    @UltraLight you taggy me

    3.3 years ago
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    38.3k UltraLight

    Well...
    1) I expected this before I even loaded this in, but takeoff speed is roughly 3x as high as it should be lol so yeah
    2) I am getting kind of squished vibes? I do not know why this always happens when builders attempt ultralights but yeah, some short-fat sort of stuff going on.
    3) Drag points are very nice, weight is about 2x too high but that is very good... most people try and eventually end up in the 1000-1500lbs range(big nono).
    4) Major improvement: move the main gear(back ones)! Move them to be right on the CG so takeoffs are safe as possible. I moved the gear forward and decreased takeoff speed by roughly 36%
    Hope you do not take this as very offensive, I tried to be nice but I am territorial of my ultralights like @rexzion is of his world war two stuff

    3.3 years ago
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    13.8k Kangy

    np

    3.3 years ago
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    12.0k 52

    @PapaKernels we will see if I leave

    3.3 years ago
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    55.6k PapaKernels

    @UltraLight so it's not supposed to be totally an ultralight, but has the bases of one, how close is it? I would like your professional opinion because you know more about these aircraft than I.

    3.3 years ago
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    55.6k PapaKernels

    @WSI thanks for the updoot!!

    +1 3.3 years ago
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    55.6k PapaKernels

    @Simps maybe, if I leave

    3.3 years ago
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    12.0k 52

    I was thinking. Am I ever gonna be able to spotlight you? Lol

    3.3 years ago
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    12.0k 52

    Awkward @PapaKernels

    3.3 years ago
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    55.6k PapaKernels

    @Simps hi...

    3.3 years ago
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    12.0k 52

    Soo.. hello

    3.3 years ago
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    55.6k PapaKernels

    @Kangy @Simps thanks for the updoots guys!!

    +2 3.3 years ago
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    55.6k PapaKernels

    @Chrisk1993 heres my entry, came in just in time, hope it does well

    3.3 years ago