Ideally, an aircraft would be made of something reasonably strong, light, and weather resistant. Cardboard, is none of those things. But that did not stop [PeterSripol] from building an ultralight wing out of cardboard.
Firstly, he wanted to figure out the strongest orientation of the cardboard flutes for the wing spars. He decided on a mix of horizontal and vertical flutes for the wing spar, with the horizontal flutes resisting vertical deformations and the vertical flutes resisting chord wise deformations.
The main spar is made up of two long strips of these cardboard pieces, glued together with a single sheet of cardboard on the top and bottom to create a structural beam. Unfortunately, the glue had not fully dried on one of the sheets before making the spar resulting in the final spar warping. Fortunately, the first wing was always intended to be tested to destruction. The wing’s ribs are made of laser cut cardboard, with doublers on the inside providing greater surface area for hot glue and a stronger rib.
Testing revealed the aft wing spar failed around 200 lbs, approximately equivalent to a 2G wing loading with a fully weighted aircraft. Since the aft wing spar broke, for the final production wings, that spar was reinforced with an separate piece of cardboard positioned perpendicular to the spar creating more of an I beam shape.
After the lessons learned from the cardboard flute orientation tests and the first wing destruction, the two wings for the final ultralight could be built. Minor changes were made from the prototype wing. After testing one wing to 150 pounds of loading, they were skinned in butcher paper to match the esthetic of cardboard. The wings came out weighing 21.8 lbs, more then ideal, but certainly workable for a single flight ultralight aircraft.
We look forward to seeing this plane fly, so stay tuned for more coverage! While you wait, make sure to check out his previous ultralight build!
imo cardboard is 2 of 3. strong and light.
I’d imagine a coat of varnish would make it 3/3, at least for the timespan of a typical ultralight flight. Still wouldn’t fly it in the rain intentionally though.
Belarussian army makes small cardboard porta-potties for their soldiers operating in the field. It looks like a square box but with dedicated hole and a flap. After it’s filled, soldier can simply burn it to dispose of feces. What’s good about it, is that it can be used by 5-10 soldiers (depends on how big their poop is) before it’s full.
Yea and the rest of the world has been selling that design for decades now go belasuckin welcome to 1969 it’s 9.99 for a w
2 pack at Walmart
Depends on definition
You won’t believe what the first aeroplane was made of!
Belarussian army makes small cardboard porta-potties for their soldiers operating in the field. It looks like a square box but with dedicated hole and a flap. After it’s filled, soldier can simply burn it to dispose of feces. What’s good about it, is that it can be used by 5-10 soldiers (depends on how big their poop is) before it’s full.
I’m a little concerned that the upper and lower spar caps in the video looked to be the same thickness/dimensions, which either screams “miscalculation” or “heavier than needed.” Upper spar cap experiences compression under normal load, while the lower spar cap experiences tension under normal load. Either way, it will be interesting to see the rest of the build videos.
Ya welcome to 1960’a tech
Let us know own when you developed a computer that runs at more than 10khz
He is not taking full advantage of the material. It would be interesting to see the input from some engineers who specialize in cardboard design.
Foamboard close enough? There are a couple that hit 6 ft span, servos available for cheap limit size. Man carry should be possible
More YouTube algorithm food…
You HAVE to stop highlighting this trash.
These people make a video for the sake of making a video, which is the opposite of what we look for is a science/maker video. The stuff they make doesn’t matter, and you are just driving more viewers to them, just like the algorithm will.
Single flight aircraft have their uses. Extensive use was made of them in WW2.
It’s also interesting because cardboard is a versatile material, and strong for its weight if you can keep it dry.
The testing process he goes through is interesting and, as with all STEM projects, helps teach the process not taught enough (or at all) in schools unless one takes science classes – the LEARNED through doing skill of critical thought and analysis. That’s why STEM should be emphasized even if a science career isn’t planned.
Cardboard is also used in other serious, commercial airborne items. One example:
Aussie company SYPAQ develops cardboard drones for defence of Ukraine
448,088 views – Mar 3, 2023
An Aussie company is playing a unique role in the defence of Ukraine. SYPAQ has developed disposable drones made of cardboard, now used by soldiers for spying, supply drops and lethal missions.
https://www.youtube.com/watch?v=-k-2W23s3Ys
The RC hobbyists at the Flight Test YouTube channel use paper covered foam board or RC aircraft. They have even tried an airfoil type ideal for dirt simple and easy foam board airfoil construction, the Kline-Fogleman airfoil, especially the KFm2 and KFm3 types.
“for RC aircraft”
A “single flight ultralight aircraft” sounds dangerous. Was it meant to say “single pilot”?
Probably both. If you check his YT channel you’ll find that Peter previously flew in a styrofoam plane!
I think this is complete folly. I hope I’m wrong but it seems Peter is willing to risk his life for clicks. If he’s building it then he’s obliged to fly in it, right? If so I hope he stays under 5m altitude.