Originally published at: 30ft remote control airplane has 50 engines | Boing Boing
…
5 Likes
Shirley it’s a matter of momentum. You need to achieve a certain amount of (mass x velocity), which you can achieve by either (a) making a small amount of air move very fast, or (b) making a lot of air move slowly.
(b) needs more engines, but involves less energy (mass x v2).
So I say USE ALL THE ENGINES.
2 Likes
This does raise the question of whether commercial airframes could use the concept of dozens of smaller engines, all coordinated by the drone’s computer. Sure, it would be much more complex and harder for human pilots, but Airbus already have purely electronic controls in their planes.
3 Likes
One day all planes will be made this way. And all the gaffer tape was on the outside which was a welcome relief.
4 Likes
As a former (like mid-80s) model airplane builder (mostly the best and coolest kind of model airplane: balsa wood sticks and tissue paper), this is heartbreaking to watch. The plane looks so shabbily hopeful that it just has to fly. But it doesn’t really.
I sort of skimmed thru, so I don’t know how much of it was hot glue and how much was hot glue, but I’m wonder “why not CA?” Maybe it would be too spendy? Also, for a do-over, I’d be tempted to try a biplane configuration, to get a bit more structural stability, and maybe look into mounting the engines so that you get more of the backblast over the top of the wing.
Now I want to build another huge (like 60 inches is huge to me) free-flight balsa wood model…
Oh this video brought me some joy. Such nerdiness, such floaty-bobby-galumphy near-controlled-flight… Maximum nostalgia, even with the irritating buzz of those engines…
10 Likes
I do so love that movie and consider it underrated.
“The son of a b**** will fly.”
9 Likes
That it is. There is so much good stuff in it.
Also one of the best adaptations from a comic, I think. Successful translation? transposition? from one medium into another with all the changes that go with that, but keeping the original spark intact.
7 Likes
The conventional wisdom in aeroplane design has generally been to use horse-sized-duck engines.
Sometimes the wisdom strayed into the realm of two horse-size-ducks are better, just in case one of the horse-sized-ducks stops working. But this philosophy was always offset by the reality that flying a thing that really needs two horse-size-ducks to be happy, on a single horse-size-duck, isn’t great.
So generally, if an aircraft has more than one motor, it’s 'cos the available horse-size-ducks weren’t big enough.
This is why in the '70s long-haul aeroplanes had four engines (or sometimes three) and now they can get by on just two.
3 Likes
“Would you rather fight one horse-sized duck or 100 duck-sized horses?”
… needs some clarification.
Hand to hand?
Proper guns?
2 Likes
I suppose the terms are used interchangeably now, but I was taught that engines consumed fuel to generate mechanical motion. Those props are running off electricity, making them motors.
Ok, now I am done being a pedant, for the moment. 
4 Likes
Yes, but new experimental designs are exploring the possibility of using many motors to create more lift over the length of a narrower wing, allowing for more efficient cruising at speed. So maybe we’ll be seeing many-engined aircraft make a comeback some day.
Edit to add:
Obviously modern electronic control systems would also make multi engine planes more practical moving forward. Check out the throttle levers for the 8-engined Spruce Goose:
Having something like that for a 50-engine plane would be perhaps a bit impractical.
4 Likes
As a follower of this guy’s channel for a few years now, I worry that one day we’re going to get some sad news - he has a history of testing out questionable home-built aircraft himself, and I hope that it doesn’t eventually bite him.
4 Likes
The multiple engine aircraft (more than two) were also a means to comform with ETOPS rules at the time, with a mind to future-proofing in case the ETOPS rules were expanded.
Flight controls for multiple engined aircraft would be awful. Having to run continuous diagnostics on all those engines? No thanks!
By the way there is a made-up meaning for ETOPS: Engines Turn Or People Swim!
2 Likes
Eight engines? A sharp pilot can handle eight engines while taking a nap.
3 Likes
Engines are for knocking down castles.* Motors are for moving things.
*Engines used in maths are properly called computers. The proper term for toothbrush, is calculator, for it’s role in removing calculus, the disovery of which is jointly shared by Fig Newton and Schoko Leibnitz.
6 Likes
Same here. I subscribed to his channel for a couple years because he has done some legitimately awesome projects, not the least of which being his ultralight airplanes. He has really has some great engineering chops.
Eventually, Sripol’s attitude completely turned me off and I had to unsubscribe from his channel. Not just his disregard for safety in so many dangerous situations, but his complete lack of care for his equipment and materials. Breaking things (purposefully or just with lack of care), throwing tools and materials that I would love to be able to afford, doing things that could endanger other people or property. I love that he is making young people interested in STEAM topics, but I hate him as a role model.
I did find Tom Stanton’s channel via Peter Sripol’s, so I will thank him for that. Tom is much more my cup of tea, with a similar subject matter but with care for safefy and respect for his tools. He also does a lot of highly creative experimental designs, which are great whether they work or fail. He always provides thorough explanations for the principles and results of his experiments, too.
4 Likes
RamyRC is a channel I enjoy following. Some fantastic work.
1 Like
The trend is in the opposite direction, though. I suspect that maintenance is the reason. It’s going to take almost twice as many man hours to inspect and maintain 4 engines as opposed to 2 bigger ones.* Once engines became reliable enough that the chance of two engines failing was not something to worry about, regulations changed to allow twin engine planes to fly over oceans. And then mostly stopped purchasing 3 and 4 engine planes.
*at least for jet engines. I suspect that isn’t nearly as true for piston engines, where the maintenance is highly correlated to the number of cylinders. 3 or 4 row radial engines were generally maintenance nightmares.
4 Likes
Oh, that is what I figured. The idea I see being explored bz this weird beastie and by the X-57 Maxwell may result in motors having to be modular, so that if Port Motor 12 shows a red warning light, the ground crew can swap it out whilst the plane is still on the tarmac.
I specifically thought of drones having this sort of tech first, as if the statement is correct and the energy usage really is lower, unmanned battery powered airframes would be the first choice.
