For anyone who doesn’t already know, Emma is the first full-time hire at Project Air 🙌 She’s an incredibly capable engineer and actually much more qualified than myself, who basically self-learned everything. Over the years I’ve had many friends appearing in my videos, including Sam, Mike and Hannah, who were always keen to lend a hand with building and filming when they were available. 🎥 What a really needed, though, was someone to help design, build and test things full-time. Emma originally worked in the same engineering company as Sam, who recommended her. I saw she was the ideal sort of engineer to come and help out with Project Air operations day-to-day. I’m really excited about all of the more complicated projects we’ll now be able to take on with her versatile skill set in electronics, CAD and other areas, and I’m also very pleased to highlight a woman in STEM through this channel, something that is still lacking on RU-vid (and in general). I’d like Emma to be treated with respect as it’s hard enough to appear on camera without inappropriate comments about her appearance or relationship to myself. She is a valued member of the team and I’m very much looking forward to all the future projects she is going to be helping with. Looking forward to the next project! James
absolutely love your videos, I have been watching your channel for a long time and your creations never disappoint. here is an idea of something you should make. one of those car plane boats you sometimes see in movies or games were you can design your own planes. maybe a buggy with floats and wings on the side or just an evolved sea plane with bigger wheels. Make sure to strap rockets to the back! I have never seen someone make it so it would make for great content. thanks for making great inspirational videos.
As a 60yr old I really appreciated seeing you take Jetex & balsa structures to the limit. I had many, and if fact although you mentioned the 50s my last was in 1985, although Jetex parts were a little hard to find by then. It was a tissue & dope plane that immediately burst into flames. Dope was still off-gassing! I dropped it immediately and it sat on the ground leaving, within 30s, a black skeleton of failure. Gutted.
Sounds like a mini Hindenburg. Too bad there wasn't RU-vid, it would have been great to film that. I'm 65 so I too remember Jetex. Great memories, even when or maybe especially when things didn't go the way you expected.
66 here, fond memories of Jetex motors. I remember them being all metal with a spring latch you'd flip to separate the two parts. 2x orangy red fuel pellets, a bit of gauze, an asbestos gasket and Jetex fuse wire. Glowed red hot if memory serves! Many a burn was had along with a huge amount of fun!!!
@@RichardIresonMusician Yes the gauze, the gasket and a tin of pellets. I also recall the small maybe 1.5" normal one and a larger one, 2.5" and fatter? The fuse wire would crack quite easily I recall. Ahhhh fond memories.
10:30 the quite hard edge of the field entering the view is quite scary... The efficiency of such a glider with ground effect makes that they can get pretty far 😂
Nice to see you revisit retro planes with modern tech. I'd love to seem more of these. Emma is also absolutely right about it looking like a kid's drawing, but it glides nicely.
Such a cool project. After seeing the table go whoosh i had my doubts but the first testflight with the smaller rocket motor had me smiling. Good job 👍
Super impressive engineering skills and glad you finally went with the box frame. I have seen some larger motors that have about 20 seconds of lower thrust, which may be more suitable for a longer flight (Apogee Components, Aero Tech G18+, 19.8seconds). You have a nice looking Dalek in your workshop!
Emma is amazing, and I’ll leave it at that! Great design, build, and testing. My only suggestion is to get a motor with a longer burn time. Aereotech makes a 38mm diameter single-use motor with 320 N-s of total thrust and a 6 second burn time. It doesn’t sound that long, but their similar sizes burn from 0.6s to 2.3s. I used one on a LOC Precision model for my Level 1 certification and it was a crowd-pleaser!
Tip - as the rocket will get lighter as it burns putting it as close to the centre of gravity as possible will help.so above or below the wing would be better. Great fun all the same 👍
Well done. Seriously interesting. Horizontal acceleration can be mitigated by converting the excess energy into altitude. If the airframe is not strong enough to manage the thrust in the horizontal, pitch up and climb. You can go higher instead of faster.
That's the standard procedure for when you have more thrust than your airframe can handle in level flight, you point it up and gain altitude instead of speed. It's a ultra high lift glider, not a high speed hotliner, the point of the rocket should've been to get as much altitude as possible for longer glide time...not see how fast you can make it go in level flight. If you're hitting flutter speeds, you're too fast and wasting the thrust on hand with drag.
im curious why didnt you use fishing line to stabilize the first plane ,you could brace the tail against the pegs that hold the main wing and brace the wing against the end of the tail ,i think it would've been strong enagh to handle not crumbling under its own weight fishing line is extremely strong and you can use it to eliminate any unwanted twisting forces by tying things to fixed hard-points on the plane
That's precisely what I was going to write! Great plane but sad seeing those wings and tail flexing when some line would have resolved most of the issues!!!
That was fun, but here's the challenge for you before you tuck this plane away for a happy retirement. Multiple rocket motors triggered one after the other. I feel we need more height.
I was thinking along the same lines, a couple of the less powerful engines, then a couple of the powerful ones triggered one after the other. It would be great to see how high it could get for longer glide time!
I know absolutely nothing about airplanes and flying but I hydrofoil surf every day. It’s so awesome to hear you talk about wing designs. My favorite wing to surf nowadays is fairly wide like a glider but fairly thing overall and very high camber. It carves wonderfully, has loads of low speed lift, and it absolutely refuses to stall even at very low speed. Now I wanna get into rc planes.
I had two copies of this book from the 60s when I was a kid (in the 90s) called Building and Flying Model Airplanes. It talked about adhesives, safe ways to spin propellers that could fire up when the glow plug was heated, and instructions to keep ballpoint pens because they contains useful springs! In addition to that it covered power systems which included Jetex! I've tried looking them up in action, but there hasn't really been anything that was worth reading about or watching on youtube. Thank you guys!
Loved the video. Back in the late 1960s a friend and I designed and built a wide wingspan glider - it was probably only 6 feet but considerably bigger than other sailplanes we built, sadly no pictures. Balsa wood with dope covering and duralumin joints between the two halves the main wing to allow for transportation. Free flight launched using a tow line. It didn't survive many flights before structural failure. Happy days. We're now in our mid 70s.
As you can see high aspect ratio wings have pretty good performance. Having the Center of gravity proper is likely the most important aspect. Love your assistance's hair. She is gorgeous. Lol
Lots of fun, very interesting, and a little terrifying (for the plane's safety)! I have found that nothing beats very lightweight, built-up balsa squares or rectangles for stiffness of long fuselages and wing spars.
The fate of the 3D-printed tail part reminds me of something an expert from a plastic manufacturer told my dad on an industrial fair a few years ago: "If you know enough about plastics, you use metals". Someone should have told Stockton Rush ...
And in some cases if you know enough about metals you use lightweight, high temp reinforced carbon composites (RCC). Metals such as titanium and Iconel are not easy to work with compared to carbon composites. Think SR-71 vs the SST. In the case of the Titan... it wasn't neccessarily the material choice per se - it was the design for the material in that case. If it was a spherical shape... it might have been a different story. It's why God didn't make eggs tube shaped. 😏 That being said... it's not well understood yet how composites fair under repeated flexing in deepwater applications, when compared to metals such as steel, titanium, or aluminum. As proved by the Russian's titanium is not a good choice as it's too expensive and hard to work with for subs. Aluminum.... ah, I don't know - you going to have the same issues with flexing and fatigue, along with corrosion from exposure to sea water. IMO steel is probably the better choice - at this time.
I actually built and flew a Jetex Saunders-Roe SR.A/1 (a model of the S/R flying boat, with auto-rudder), in the late 50s ! It was my first model aircraft, and it worked so well, it just flew and flew - right out of sight ! I was devastated, and thereafter stuck to control-line flying, until r/c models became a thing
Im only half way through..... Carbon fiber square tube on tail would work..... Need larger servos. It may turn ok but it would do better with a little dihedral in the center section. Not sure where you got your airfoil.... The idea of using an under cambered wing is solid. But usually the camber is behind the wing spar which should be close to the center of gravity.
Even triangular foam board -simple, cheap and rigid geometry - beats cute and expensive (where there is no optimisation nor competition at the bleeding edge)..
It's cool, but nothing new, even in size. Back in the 80s, we had to make our own rocket motors and did the samething. I'm really not trying to poo, poo your success it looks far better than what we made. You did a great job. There was very little out there to help build these planes, gliders, rocket motor, and rockets. With no internet, computers, and very few hobby stores, we had to make most of what we needed. But it was fun, we failed many times, but in the end we met our goal...it's too bad we didn't have cell phones to document our adventures, laughter, failures, and achievements. I'm almost 70, and it's great seeing what the young people are coming up with. It's truly innovative !
Really nice project! That worked really well. Have you thought about having Emma doing some presenting? It would be great to have an extra perspective? Or is she mainly interested in the engineering. It would be great if you could convince her to do a few behind the scenes shorts at least (and give you more content).
An horizontal stabiliser is NOT a lifting device, but rather pushing the tail DOWN to counteract the tilting moment of the main wing. So should have, if any profile, a symetrical one.
A great project, James, both thumbs up! It seems, though, that if one's aiming for distance it's better to launch a rocket on a ballistic trajectory, than to power a glider, even though the latter has a great lift-to-drag ratio?
The rocket glider I watched take off around 1967. The guy launching the glider, launched it like a rocket to get as much height before the rocket stopped and the glider took almost 30 minutes to come down. The glider circled around as us kids kept track of it running all around the park where it was launched, we wanted to be their when it touched down. That is just about all I remember of the glider. I do believe the glider reached around 125 feet on a worm day with lots of up drafts. Watching your video brought back memories. thanks.
I once walked into a hobby store and saw a rocket powered twin tail glider already pre built and hanging from the ceiling. Long story short, I bought it and a pack of rocket motors, took it to the park the next day and 3. 2. 1. 💥🔥 Exploded on ignition. 😢 I should have sued Estes for the motor failure, 150 bucks right out the window.
06:08 you should use forged carbon part instead of that 3d print. its not hard to make and it'll be stronger and lighter. and instead of using a single tube use 2 tubes to increase the torsional stiffness of tail
Exactly . 3d printed compression mold stuffed with fibers and resin . Did a fair share of them . Mold is one time use only but results are more then worth the effort
@@VIJAYzk OK depends on design I think . I made mine with simple pla no demolding angles nothing .just a coat of PVA and after drying I would temper the part to full hardness . After that I simply broke away the mold.
I flew Jetex in the 50s and early 60s. Had a few burnt fingers but experimenting with rocket powered, Balsa-built aerodynamic configurations was a blast! Thanks for building on that modeling legacy!
*Title: Building the World's Largest RC Rocket Plane* * *0:01* - Intro and inspiration behind the project (Jetex rocket planes from the 1950s). * *0:59* - Discussing the configuration and design of the glider. * *1:11* - Building and testing balsa wood prototypes. * *3:24* - Lessons learned from the prototypes and scaling up the design. * *3:32* - Construction of the giant 19ft wingspan using carbon fiber tubes. * *4:43* - Concerns about the wing's flexibility. * *5:48* - Building the tail surfaces in a v-tail configuration. * *6:11* - Construction of the fuselage. * *6:22* - First test flight and initial observations. * *8:17* - Fixing the tail's flexibility issues. * *8:52* - First radio-controlled glide test. * *9:32* - Rebuilding the fuselage with a stronger box-style design. * *10:01* - Final test flight with the new fuselage. * *10:46* - Practicing launch techniques. * *12:06* - Building a heavy-duty rocket mount. * *12:53* - Sponsor message: PCBWay. * *14:01* - Preparing for the first rocket-powered test flight. * *15:00* - First rocket-powered flight with a smaller engine. * *17:11* - Second rocket-powered flight with a larger, more powerful engine. * *18:36* - Success and reflection on the project. * *19:13* - Outro and call to action. I used gemini-1.5-pro-exp-0801 to summarize the transcript. Cost (if I didn't use the free tier): $0.07 Input tokens: 19072 Output tokens: 413
ProjectAir, you've excelled yourselves! That was a beautiful piece of Aeronautics. Nail-biting flutter on the larger motor, but it held together. Perhaps a steeper climb angle, and a tiny bit of leading-edge sweepback? Others have suggested multiple motors firing one after another; seems worth a go.
If you look closely at the wing camera footage, on the second flight, after the motor burns out, you can kind of see the air flowing over the wing with the little bit of smoke coming off the engine. Really cool.
Watching you launch this plane made me think of how atlatal darts are thrown. If you tied a string with two loops on either end and looped one end onto a nail on the back of the plane, you could use the other end on your finger to extend your launch with one hand. Maybe not necessary for this project, but it would be cool to see a atlatal style glider launcher or something similar. Great video!
I remember my older brother building Jetex planes in the late fifties early sixties ,they had an unfortunate habit of going down in flames ? Emma definitely must stay and launch all your aircraft in the future ,what a sweetheart.
Wow, that right wing tip almost departed during rocket burn ha ha. Well done James and Emma, looking forward to seeing more positive energy from you in the future.
I built a 1.6m wingspan glider with diy rocket motor approx 10 yrs ago. This is fun! good memories. I bungee launched the glider, then activated the rocket with a short circuited carbon based resistor(they will glow red).
Awesome project thanks for sharing. One thought I had while watching, if you replaced the square tube with triangle tubing the weight is reduced by a third and the triangle shape is actually the strongest.
I built a few rocket powered gliders, but they launched straight up and then the rocket motor was designed to blow off and float down on its own with a parachute and then the glider would circle down. Built up a larger RC glider with a similar launch concept and much bigger engine, but was too scared to ever try it. Didn’t have a nice big field like you found!
Wonderfull works guys... to stabilise the wings I advice you to use dinema fishig cords, a .2 mm dinema can hold up more than 10 kilograms pulling force, you cand configure some diagonals between the tips os the wings and back to the tail and give more rigidity to your frame without adding any air drag.
Carbon fibre saved you're ass in the wing structure. Godly material and it just shows what the right material at the right time can do. Well done, absolute legend
In modern airplane design, the center of gravity is NOT aligned with the center of lift! In fact, the CG is usually 1/4 to 1/3 of the MAC (mean aerodynamic chord) ahead of the CL. That moment is countered by the horizontal stabilizer producing negative lift. In order to reduce or eliminate porpoising, you adjust the moment arm of the horizontal stabilizer as well as the distributed mass forward and aft of the CG.
In America we make Combat planes. Cheap wings and a 31.75mm aluminum square box tube fuselage. No twisting square box, unlike rounds. I would use Polyhedral wings, are used in aircraft for various reasons, mainly to improve roll stability without significant change in the overall wing ..
What I don’t understand is that even with all the virtues of social media like RU-vid and the internet people trying to reinvent the wheel?! Without taking the blinders off and looking over the edge of the plate. Making mistakes that are not necessary. The Ukrainians are quite inspirational in drone craft building and developing on the fly.😊