I Learned About RC Flying From That F 4 Crash

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I Learned About RC Flying From That F 4 Crash

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Күн бұрын

I Learned About RC Flying From That F 4 Crash
In this video I will go over what I learned about RC flying from a crash of my foam board F-4 Phantom model airplane.
I had designed and built a foam board version of a radio control F-4 model airplane. I took as inspiration, and this is discussed in the video, my success building and flying a foam board model of the F-22 flyer.
The F-4 went together well, with the correct center of gravity and sufficient power. However, the model crashed on its first flight after a hand launch.
After a review of the crash video, I concluded that the F-4 had its motor mounted at the nose of the airplane, quite a distance from the center of gravity. This motor was heavy enough that at low airspeeds the elevators were just not effective enough at the low airspeed of a hand launch to be effective, thus the F-4 RC model crashed. This was not the case with the F-22, as the motor was mounted very near the center of gravity, thus the large elevons were effective at keeping the nose up at low airspeeds.
Here is a link to my KZfaq Channel:
/ timmckay56
Many thanks in advance for a post of this video on Facebook, it truly helps the channel a lot!
Regards,
Tim
F-22:
• F-22 Foam Board RC Air...
QCAD:
• QCAD Tips & Tricks for...
Chapters
00:00 - Intro
00:18 - Project overview
01:43 - F-22 background
03:06 - F-22 lessons learned
03:53 - Building the F-4
05:21 - F-4 discussion
06:09 - At the field, test flight
07:13 - Lessons learned
10:05 - Conclusion

Пікірлер: 33

@jhuff8596 2 жыл бұрын

Great video Tim! I was just a bit disappointed that you didn't come up with a way to incorporate a chocolate fountain into the video!

@TimMcKay56 2 жыл бұрын

JH: Working on the fountain! 😁 Tim

@jhuff8596 2 жыл бұрын

Cheers Tim have a great day!

@jroar123 Жыл бұрын

Fast Note: I am 59 years old and not a kid although I am a kid at heart when it comes to building models as a hobby. I just completed a Chinese Pirate Junk ship with incredible detail. Currently I am building a German WW1 triplane Fokker 1. Instead of tissue I chose to go with moncoat. To say the least it is a real challenge which makes it fun. With all the new FAA rules and being forbidden to fly (or video) in parks, I have put flying on hold for awhile until I can sort out what keeps me legal. Thank you so much for these videos.

@TimMcKay56 Жыл бұрын

No worries and thanks for checking in! Tim

@craigsawyer6453 2 жыл бұрын

I taught my children to use full throttle for take off when hand launching RC planes (why is it that they try, at least once, to get a plane in the air with cruse power?). We eventually started including a hand launching tab on the underside of the fuselage to assist in take off speed and trajectory.

@TimMcKay56 2 жыл бұрын

Craig: Fully agree. The challenge, at times, is our electric RC models are so overpowered that full power may be too much for the initial flight. But I take your point. Tim

@randall4411 2 жыл бұрын

Thanks for another interesting video Tim .

@TimMcKay56 2 жыл бұрын

Randall: Glad you enjoyed it! Tim

@bullyhys Жыл бұрын

Hi Tim, Nice Video, suggestion add aprox 1-2 deg of incidence to your F4 wing if you do a rework. I fly Profile scale Control line planes, and found with Flat wings it really helps, I have built and flown many assorted such models and the most successful were the ones with a slight amount of incidence. MD

@TimMcKay56 Жыл бұрын

Bully: Agree 100%! I always add a bit of positive wing incidence to all my RC models. Tim

@greg0063 2 жыл бұрын

Hobby King had a foam board F4 in the Blue Angels trim, the motor was on the back. It was ok at best, it flew well enough but not great. I agree with you that the F-22 looking planes (F-15, su-35, mig 29) lend themselves to very nice flying models. And have a distinct advantage over conventional looking parkjets.

@TimMcKay56 2 жыл бұрын

Interesting! Tim

@Steve25g 28 күн бұрын

@@TimMcKay56 I did build a SU27, that was 'slightly' overpowered, with the whole tailsection used as elevons. Ended up having to much authority. (as in, pulling a looping, in less then a meter diameter), stressing the frame to much, snapping in half. I did have a balsa F4 kit, power by a .61 webra blackhead, running a 10x7. I got the kit as build, from a store, balance was problematic. As in using loads of lead in the tail, even mounting battery in tailsection. The engine was mounted slightly tilting up, tailsection slightly negative. the F4 took off, flew perfecly. Problem was landing, pulling up, to slow down a bit, ended up slowing me down to much, and the 10x7 could not help me gain speed. Ended up going down in a mais field, tail down. Being a controlled crash. Maybe some tips, from my balsa model that can come in handy, for foamy ?

@TimMcKay56 28 күн бұрын

@@Steve25g Interesting story!

@1mikeb 2 жыл бұрын

DIY designs sure can have a lot of complications. I think your assessments are probably correct. If you had gotten the plane up to speed with a running toss or use of landing gear, I think it would have flown. Maybe needed some more right thrust based on the left roll as you released it? Maybe a higher rpm motor with smaller prop because of wing size? Maybe more thrust was needed because of wing size and lack of air foil? So many things to test. But I do think that same air frame would fly with some changes.

@TimMcKay56 2 жыл бұрын

Mike: Thanks! Much like the real F-4, these swept wing high performance designs just need a lot of airspeed to both take off and fly. A gentle hand toss will not cut it! Tim

@edsherrod5216 2 жыл бұрын

Nice job, Tim! It is tough to see a creation you built not go more than 5 feet on the first flight. I am sure if you decide to redesign the F4, it will be a success!

@TimMcKay56 2 жыл бұрын

Ed: Live and learn in the RC plane design hobby! Tim

@paynecharlie4087 Жыл бұрын

I was watching video, and I think that you could mount the motor as you did for the f22 , I think you would have a great flyer.

@TimMcKay56 Жыл бұрын

Am thinking of doing this. 😊 Tim

@markpatterson4917 2 жыл бұрын

Hi Tim don't think you can get away with under arm launches with an aircraft like that. With the prop being forward you can give an over arm launch like a dart from just behind the wings. Launching this way gives more airspeed. I built a large(ish) phantom chuck glider (15"span balsa) when i was 12 it flew really well. The upturned wingtips made it very stable. From your footage think the torque of the motor and lack of airspeed lead to the casualty. You may let someone else launch it for you in the future. The sooner you have input on those sticks the better every little helps. Surely you can mend it I didn't look to bad splice a bit of carbon to stitch the cracks and were good for take two. Looked a nice home build and like you say if you do a second revised version a larger wing area will always helps. Great video as always look forward to version 2 if you can't rescue the first one.

@TimMcKay56 2 жыл бұрын

Mark: Thanks for this input! Tim

@funscalemodels9782 2 жыл бұрын

Hi Tim, great video and good discussion. After looking at the video, my .02 worth would be: Not a enough power applied before launch. It didn’t sound like the prop was winding up. With a prop jet you can get away with a smaller prop at a higher rpm and not have the same torque impact like say a large 3-blader. The toss looked not not be “firm” enough. As this is a flat wing, there is additional speed needed for it to create lift vs a convention airfoil. I’m not sure the motor placement is as impactful due to these other factors. Sorry to see the model end this way- hoping you do another 😁

@TimMcKay56 2 жыл бұрын

FSM: Fully agree. Gotta have the motor at full RPMs and heave as hard as possible. Next time! Tim

@CliffHarveyRCPlanes 2 жыл бұрын

Perhaps a catapult to launch up to speed, hindsight is a marvellous thing, either that or long grass, cheers 👍

@TimMcKay56 2 жыл бұрын

Roger that! Tim

@frankienv3906 2 жыл бұрын

Phantom F4 is one of my favorite aircraft, seen in the Vietnam war era. Note sometimes Hand launching can be the cause of a crash due to the fact that the plane suddenly finds itself in the air before enough speed and air flow develops over the control surfaces, making the control surfaces useless until the plane is traveling fast enough., A nice fast ground run on takeoff usually avoids this situation. Also a word of advice to anyone whom wants to build foam planes in the future, Don't use EPP foam its to soft, its like build a plane out of a kitchen sponge ..lol

@TimMcKay56 2 жыл бұрын

Yeah, for a beast like this you essentially need a Navy carrier cat launch. Tim