what I LOVE about American entrepreneurialism / exceptionalism is that 1. they are prepared to fail 2. they are prepared to fail in front of you and their kids and 3. they are comfortable publishing failings here for you to learn learn from. 4. they refer to their mentors / inspirations and influencers - for you to refer to. HUGE KUDOS to Ben Harber.
That laugh at the third attempt is priceless...teaching your kid to laugh and learn from failure, to see failure as entertainment on the way to discovery, is a life hack everyone should come to understand...Super dad right here!!!
So a few things, one EDFs need a clean round smooth exit. you want a FSA of around 90% to the diameter of the fan meaning your exit needs to be safe for example around 48 mm. The more 1 to 1 you can get the better your trust ratio will be so if you have a 50 mm fan and you your exit air is 50 mm you will have the most trust but lose a little top in speed. Number to any time you have a push or configured aircraft regardless if it is prop or EDF you want up trust. Do you need to push the tail down nose up. So personally I would take your EDFs back out hollow the entire tail section out make yourself a pair of thrust tubes out of my Mylar and give it around 3 to 5° of upthrust angle.
Applause all round!! This is way cool!!! It needs a ton more air in and out. Open the intake/exhaust up. Spank that kitty, it'll fly. I have the Xfly A-10 and it wants to leave before the hand toss. AirHammer out!!
Have you checked that you are getting enough air into the edfs....and the maximum thrust out the back? It's looking under powered I think 🤔 Good fun experiments anyhow 😊
Hey Ben! Remember me from work (RC flying demos at the company in HB?)? I retired last year. Glad to see you on the tubes...I'm building old school balsa RC from scratch in my spare time. Take care and keep flying!
check the thrust on the edf's. might need one large edf instead of two small ones. and tie in the underside intake because i honestly dont think the top two intakes you did are big enough
Hi! Great experiment! Did you check that the flight controller was not reversed? (applying down elevator instead of up elevator) Didi you try flying in manual mode? Just ideas.
Nice paint job, Ben! I think your CG is a bit too far forward when the battery is on top, causing the plane to pitch downward. When you moved the battery to the bottom, it brought the CG back, but it also lowered the CG below the thrust point, which would also cause it to pitch downward. I wonder if you kept the battery on top and made room to move it backwards, if you'd have better success. Love the video, keep it up! Tom
nice video ... very entertaining ;-) i guess one of the additional comment is, I found that the air intakes hole is way too tiny, and it doesn't have enough thrust power to lift the wing, usually the intakes hole is larger than the out-hole.
edf's, especially the ones he's using, have pretty awful static trust but make up for it with high top speed. these should be more than enough, just need a high launch speed.
I couldn't see what the blade count of plane ..but a 10 blade 50mm can give you as much as 380 watts ,going by the old rule of thumb on EDF's of 10 watts of thrust per every ounce of plane x 2 , they should fly a 4.25 pound model. Get rid of the intake doors so the fans can breath and extend the exhaust farther past the end of the fuselage at a slight up angle. Also the wings need about 3 degrees of washout at the wing tips. A good example of seeing what washout does is watching the F16 fly from the sides, it flies in a nose up angel of attack and the wing tips are level. Your F4 would also fly better with washout built into the outer tip panels.
Try adding some Canard's on the nose, after you rebuild the front nose section. Also try adding a bit of length to the nose section as well . And by the way, I love scratch building aircraft with all the thought-provoking problems they may bring lol! Also, I like to share, that I am working on a scratch-built RC Flying Saucer at present. Keep up the good work.
It's so incredibly fun to build from scratch, so even on those occasions I have moments like yours, it just doesn't matter, because I had fun building something. I imagine you are the same way... and wow! That plane is TOUGH, lol! My current build project is a 60" span boomerang jet knock off for an 80mm fan.
Some pointers: 1. I cannot see any reflex, so nose diving is a given 2. I had the same launch issues (other than point 1) with an EDF plane I built and my exhaust size was too restrictive. If you are not interested in a few more mph speed, then 50mm fans need 50mm exhaust 3. Those inlets look too small as well and with point 2, you are not getting enough thrust due to air restriction
As soon as you said it had EDFs I was like oh someone has to have some skills to get that to work. Then you launched it... EDFs are a pain to get working right. Best of luck!
Maaan I was really rooting for you on this one! I had just received two 50 mm 12 bladed counter rotating (CW & CCW) DF from Bang Good. I'm currently in the prosses creating my own design (in my head) what I'm going to do with these fans. I'm thinking of somehow designing them to mount directly on elevons for thrust vectoring and mixing in vectoring in the rudder channel. I'm assuming you have the 12 blade fans like mine? What little we got to hear; your fans sure sounded sweet!
I'm sure you have it sorted by now but I reckon you need to allow more time for thrust to build up before throwing. Your launches were all on a level or dlightly downward trajectory - try launching under-arm with an upward follow-through. Finally I would give a bit of up trim on a switch, which can be disengaged once she's flying up and away from you.
It may not have flown this time but I'm sure you will tweak the design enough to get it airborne and I got to say it looks like an absolute beast (Like a shark). Nice one Ben and great job camera man.
I built a Flerken, took many hours to build, flew it 30 seconds. I suspect that a survey of Flerken builders would reveal more failure maidens that successes.
Fun vid, failure is a part of all experimentation. Your son was having fun. I fly slope so I don't have much powered flight experience, but to me it seemed you are lacking thrust in relation to the overall weight of the aircraft. In powered videos I have watched where the plane flies well it always seems like the plane wants to come out of the launchers hand. Just my 2 cents.
You definitely titled this video properly. It may not work just yet... But I know you'll figure it out. I love that you stop at nothing with your creativity Ben! You experiment and try things no one would even begin to attempt. And that's why you come up with the coolest, and most unique stuff. I'd still love to see you make another attempt at the dark angel... Another potential idea... I'd love to see you come up with a VTOL. I know you could figure it out.
Did you measure the thrust from this ducked design? Basically with two big batteries, it's a brick and it will require lots of thrust. This bird really didn't jump out of your hand. I'm guessing it is underpowered. Otherwise I like the design.
Looks good 😎👍but a little underpowered until it can reach flying speed, I think that's normal with EDF's and with the flight stabilization receiver's they will try and level the plane still causing it to pancake into the ground, that's my experience with them unless you can get the settings just right so you have enough elevator control.
looks cool but yeah waaaay under powered, those EDF's defiantly arnt getting enough air flow and are probably to small. Maybe some larger cutouts with more direct flow to the EDF
examine the way you are throwing it at the start. the throw arc is convex end of arc leading toward ground. throw inverse that under hand more end of arc up...if you can work that out. think about battery position more center mass and maybe hot swappable outside airframe even on top of fuse with dock slot area.
I think you have a thrust problem, or lack there of. Fluids, like air or water, act funny when flowing through tubes. Basically, the closer a fluid gets to the sides of a tube, the slower it flows. (It's a surface stickiness vs volume thing.) You can cheat this problem a little by putting the fans at the back of the plane and making the exhaust as unobstructed as possible.
Hey I noticed it has an internal Jet system much like the RC Black Widow, Idk if it will help but maybe look at how those are done and it might give a good insight to why yours is acting like so, I'm a beginning RC hobbyist so forgive me is my advice is stupid Lol
50mm fans are not very efficient, one 70 would be better. You need more up elevon (reflex) and a higher launch speed. Thrust vectoring will help. Hopefully you will get this figured out before you are left with just Kitty litter.
Looked like too many of my maiden flights ...lol . Of course they were mostly models of the YRF-4E, a plane that has vexed me for many years, thevprototype flew well but was free flight. It's much larger brothers have met with the cruelest of fates ...yes I am building two more ...insanity. the one that survives maiden, will be given to the USAF Museum, to replace the one they lost ...take care.
Hello Ben, I am not going to comment on what might be wrong here, Only what you are doing right or(Wright). IF you get this design to work, And work Well, Do you realize you Just may be able to Patent a Credible flying model , Or Mods there of another persons model, You may have Model company's knocking at your door, You need to keep up and do what you love. I am almost 67 and been building and flying RC planes for about 55 years. Get that Bad Kitty to rip proper, You will have offers in the industry! Do the Math! Make it Fly! Good luck and Stay Safe.
what your missing is whats most important. CG , check out some you tube vids on fuse CG, were it is to appose were you think it is. when you learn how to measure it. start with Newtons weight equation and see what u think or just keep check your airplanes durability
![Flite Test: Boomin Flerken [Review]](http://i.ytimg.com/vi/z3vlbzd9j4s/mqdefault.jpg)
what I LOVE about American entrepreneurialism / exceptionalism is that 1. they are prepared to fail 2. they are prepared to fail in front of you and their kids and 3. they are comfortable publishing failings here for you to learn learn from. 4. they refer to their mentors / inspirations and influencers - for you to refer to. HUGE KUDOS to Ben Harber.
That laugh at the third attempt is priceless...teaching your kid to laugh and learn from failure, to see failure as entertainment on the way to discovery, is a life hack everyone should come to understand...Super dad right here!!!
Sick paint job. I like that this promotes continues innovation and not being afraid to fail, even on such a public platform. Keep positive.
Do the EDFs have access to sufficient airflow?
So a few things, one EDFs need a clean round smooth exit. you want a FSA of around 90% to the diameter of the fan meaning your exit needs to be safe for example around 48 mm. The more 1 to 1 you can get the better your trust ratio will be so if you have a 50 mm fan and you your exit air is 50 mm you will have the most trust but lose a little top in speed. Number to any time you have a push or configured aircraft regardless if it is prop or EDF you want up trust. Do you need to push the tail down nose up. So personally I would take your EDFs back out hollow the entire tail section out make yourself a pair of thrust tubes out of my Mylar and give it around 3 to 5° of upthrust angle.
Applause all round!! This is way cool!!! It needs a ton more air in and out. Open the intake/exhaust up. Spank that kitty, it'll fly. I have the Xfly A-10 and it wants to leave before the hand toss. AirHammer out!!
Have you checked that you are getting enough air into the edfs....and the maximum thrust out the back? It's looking under powered I think 🤔
Good fun experiments anyhow 😊
Doesn’t look like there’s enough intake volume for the EDF’s to function properly.
Should add a control surface behind the nozzles for some thrust vectoring
Best camera man/ commentator ever! Best of luck with the build.
This is how I feel when nobody is looking! You guys are great
Hey Ben! Remember me from work (RC flying demos at the company in HB?)? I retired last year. Glad to see you on the tubes...I'm building old school balsa RC from scratch in my spare time. Take care and keep flying!
No doubt you’ll get her flying amazing. Bad kitty will get its wings!
That’s what FT is about. Taking an idea, make it yours, and make memories along the way.
This reminds me of McDonnell-Douglas' engineering of the F-4 Phantom II. Start with a cinder block and keep adding power until it flies.
Build! Fly! Crash! Repeat! I think I'll build my Flerken stock, but it's sure fun watching different ideas and experiments with the design.
Nice guys!
That discus launch was unique!
Impressive camera work😎
check the thrust on the edf's. might need one large edf instead of two small ones. and tie in the underside intake because i honestly dont think the top two intakes you did are big enough
Hilarious, love your son's laugh! Neat project. EDF Flerken is a great idea!
Hi! Great experiment! Did you check that the flight controller was not reversed? (applying down elevator instead of up elevator) Didi you try flying in manual mode? Just ideas.
Nice paint job, Ben! I think your CG is a bit too far forward when the battery is on top, causing the plane to pitch downward. When you moved the battery to the bottom, it brought the CG back, but it also lowered the CG below the thrust point, which would also cause it to pitch downward. I wonder if you kept the battery on top and made room to move it backwards, if you'd have better success. Love the video, keep it up!
Tom
nice video ... very entertaining ;-)
i guess one of the additional comment is, I found that the air intakes hole is way too tiny, and it doesn't have enough thrust power to lift the wing, usually the intakes hole is larger than the out-hole.
What about some small upturned canards, like the Viggen? Could help get it launched?
You last launch the way it was floundering made me think it wasn't getting enough thrust.
I think the intakes are to small
edf's, especially the ones he's using, have pretty awful static trust but make up for it with high top speed.
these should be more than enough, just need a high launch speed.
@@index7787 so you think it needs a catapult launch?
Catapult for sure.
Launch assist will not work with no airflow over surfaces
I couldn't see what the blade count of plane ..but a 10 blade 50mm can give you as much as 380 watts ,going by the old rule of thumb on EDF's of 10 watts of thrust per every ounce of plane x 2 , they should fly a 4.25 pound model.
Get rid of the intake doors so the fans can breath and extend the exhaust farther past the end of the fuselage at a slight up angle. Also the wings need about 3 degrees of washout at the wing tips.
A good example of seeing what washout does is watching the F16 fly from the sides, it flies in a nose up angel of attack and the wing tips are level. Your F4 would also fly better with washout built into the outer tip panels.
Defiantly a thrust issue; seems like those EDFs might need more air???
Its great that you are doing all of this with your son. Build together, let him fly. Nice movie :)
A man after my own heart: plans are just a suggestion!
That was nothing… but it was definitely something!😂
Try adding some Canard's on the nose, after you rebuild the front nose section. Also try adding a bit of length to the nose section as well
. And by the way, I love scratch building aircraft with all the thought-provoking problems they may bring lol! Also, I like to share, that I am working on a scratch-built RC Flying Saucer at present. Keep up the good work.
Hey, my lawn needs aeration, wanna come by and poke holes in my yard?
It's so incredibly fun to build from scratch, so even on those occasions I have moments like yours, it just doesn't matter, because I had fun building something. I imagine you are the same way... and wow! That plane is TOUGH, lol! My current build project is a 60" span boomerang jet knock off for an 80mm fan.
Some pointers:
1. I cannot see any reflex, so nose diving is a given
2. I had the same launch issues (other than point 1) with an EDF plane I built and my exhaust size was too restrictive. If you are not interested in a few more mph speed, then 50mm fans need 50mm exhaust
3. Those inlets look too small as well and with point 2, you are not getting enough thrust due to air restriction
it actually looks like you are throwing it at the ground.... 10:08 that laugh tho!!! love it!
If at some future time you want the anhedral look I suggest some washin on the wing tips. You also need more reflex in the trailing edge
As soon as you said it had EDFs I was like oh someone has to have some skills to get that to work. Then you launched it... EDFs are a pain to get working right. Best of luck!
You launched into a Lomcovák! Pretty neat trick. I look forward to a more successful Rd. 2. 😎
Very entertaining if nothing else! Good times.
Try a Over-Under arrangement for the EDFs? 🤔
Maaan I was really rooting for you on this one! I had just received two 50 mm 12 bladed counter rotating (CW & CCW) DF from Bang Good. I'm currently in the prosses creating my own design (in my head) what I'm going to do with these fans. I'm thinking of somehow designing them to mount directly on elevons for thrust vectoring and mixing in vectoring in the rudder channel. I'm assuming you have the 12 blade fans like mine? What little we got to hear; your fans sure sounded sweet!
Did you try a chuck test? That last discuss launch looked cg suspicious to me...
I thought the same as the two gentlemen who said it wasn't getting enough thrust, so perhaps too heavy. and maybe some reflex in the elevons?
I've studied your edf launches and know where you went wrong here. You didn't kick your left leg up before launching. Its all in the left leg! LOL!
I know when someone is showing off for their kid. What a fun day! :)
I'm sure you have it sorted by now but I reckon you need to allow more time for thrust to build up before throwing. Your launches were all on a level or dlightly downward trajectory - try launching under-arm with an upward follow-through. Finally I would give a bit of up trim on a switch, which can be disengaged once she's flying up and away from you.
That was so funny! Great laugh! Keep on trying, looking forward to a successful launch!
pusher prop on the back. reminds me of the funjet a little.
Go Bengals! we don't need no stinkn props! What an awesome airplane.
Maybe instead of 2 50mm EDFs use a single 70mm? Also adding more cheater holes might have helped.
For stuff like this my dad would use the idiom... "Looked good on paper." 😊
How’s the CG, and nose heavy !
Nice work
It may not have flown this time but I'm sure you will tweak the design enough to get it airborne and I got to say it looks like an absolute beast (Like a shark).
Nice one Ben and great job camera man.
Your mods were fun! The crashes were very entertaining. Add some tape, 2000 mah and get cg back more? Thanks for posting this.
I built a Flerken, took many hours to build, flew it 30 seconds. I suspect that a survey of Flerken builders would reveal more failure maidens that successes.
That was cool. ;You'll get it!
Batts seem to large/heavy, try 2 1300 to 1500 mah 4s and see if that helps. Nice setup and very cool plane hope to see it in the air soon.
Great experiment. Bad kitty!
Fun vid, failure is a part of all experimentation. Your son was having fun. I fly slope so I don't have much powered flight experience, but to me it seemed you are lacking thrust in relation to the overall weight of the aircraft. In powered videos I have watched where the plane flies well it always seems like the plane wants to come out of the launchers hand. Just my 2 cents.
You definitely titled this video properly. It may not work just yet... But I know you'll figure it out. I love that you stop at nothing with your creativity Ben! You experiment and try things no one would even begin to attempt. And that's why you come up with the coolest, and most unique stuff. I'd still love to see you make another attempt at the dark angel... Another potential idea... I'd love to see you come up with a VTOL. I know you could figure it out.
Lift down?
You don’t seem to have any reflex on the elevons.
Did you measure the thrust from this ducked design? Basically with two big batteries, it's a brick and it will require lots of thrust. This bird really didn't jump out of your hand. I'm guessing it is underpowered. Otherwise I like the design.
I think they call that self flagellation 🤣 but it also could be amazing tenacity Always entertaining. 👍
Looks good 😎👍but a little underpowered until it can reach flying speed, I think that's normal with EDF's and with the flight stabilization receiver's they will try and level the plane still causing it to pancake into the ground, that's my experience with them unless you can get the settings just right so you have enough elevator control.
☃️one tuf plane, thanks for sharing.
looks cool but yeah waaaay under powered, those EDF's defiantly arnt getting enough air flow and are probably to small. Maybe some larger cutouts with more direct flow to the EDF
It's either too heavy or the batteries need moving more to the middle.
I have to say before it even flies I'm sure you would get more power out of it if you covered around the EDF area
I think what you have comes under the heading of either a Hangar Queen, or a Lawn Dart.
examine the way you are throwing it at the start. the throw arc is convex end of arc leading toward ground. throw inverse that under hand more end of arc up...if you can work that out. think about battery position more center mass and maybe hot swappable outside airframe even on top of fuse with dock slot area.
It may be just too heavy on the wing loading.
That's why they design it for propeller, those two little EDFs will not give you the thrust you need!!!
I think you have a thrust problem, or lack there of. Fluids, like air or water, act funny when flowing through tubes. Basically, the closer a fluid gets to the sides of a tube, the slower it flows. (It's a surface stickiness vs volume thing.) You can cheat this problem a little by putting the fans at the back of the plane and making the exhaust as unobstructed as possible.
You learn more from your failures than you learn from your successes ... if you're paying attention!
very unique video, frisbee launching rather cartoonish
It looks like there is not enough thrust from the engines. If your getting enough thrust, it should rocket off without dropping like it did.
Hey I noticed it has an internal Jet system much like the RC Black Widow, Idk if it will help but maybe look at how those are done and it might give a good insight to why yours is acting like so, I'm a beginning RC hobbyist so forgive me is my advice is stupid Lol
It looks like there’s not enough thrust to gain lift to the weight
50mm fans are not very efficient, one 70 would be better. You need more up elevon (reflex) and a higher launch speed. Thrust vectoring will help. Hopefully you will get this figured out before you are left with just Kitty litter.
drops like a rock
Looked like too many of my maiden flights ...lol . Of course they were mostly models of the YRF-4E, a plane that has vexed me for many years, thevprototype flew well but was free flight. It's much larger brothers have met with the cruelest of fates ...yes I am building two more ...insanity. the one that survives maiden, will be given to the USAF Museum, to replace the one they lost ...take care.
You didn't give e it a hard throw, need more airspeed because of the aspect ratio of the wing.
I tried a 50mm and it didn't work but I have a video with a 70mm and it does indeed fly 😁
Hello Ben, I am not going to comment on what might be wrong here, Only what you are doing right or(Wright). IF you get this design to work, And work Well, Do you realize you Just may be able to Patent a Credible flying model , Or Mods there of another persons model, You may have Model company's knocking at your door, You need to keep up and do what you love. I am almost 67 and been building and flying RC planes for about 55 years. Get that Bad Kitty to rip proper, You will have offers in the industry! Do the Math! Make it Fly! Good luck and Stay Safe.
EXCELLENT
Doesn't look like wings have enough shape to disrupt hi low air for any kind of lift ...
what your missing is whats most important. CG , check out some you tube vids on fuse CG, were it is to appose were you think it is. when you learn how to measure it. start with Newtons weight equation and see what u think or just keep check your airplanes durability
Looks like you need front canards
its simple, need more thrust, and more angle in the elevons
That's one tough model
Put the tail fins on the underside of the fuselage, and "fly it upside-down"
Your son is adorable haha
On the last try, the CG was way off I'm afraid. But hey, that's how this hobby goes.
1:02 lemme just build one and throw one of my 25FX two strokes on it...
it's tuff, ill give it that.
Point it up when you toss it up. NOSE UP!
It's successful if it was meant to be ground seeking.
I think your weight to power ratio is off a little
we put a 70mm in ours lol
Careful where you point that thing. You could lose an eye! LOL!
Airflow is the problem for your motors. you should cut off the lapels to improve airflow in.