Mike, I sensed no patronizing at all and thank you for the time and examples. My courses in higher maths at times touched on fluid dynamics but the system that is an aircraft, and particularly a model aricraft, were never mentioned. I suspect much MatLab and Labview stuff exists to support the current design schemes.
This sidecar discussion would do for a fine separate topic as many modellers would benefit from the practical results from experiment/tests.
The flying wing design was discussed at length in the 1938 issue of "Model Glider Design" by Frank Zaic. Oh what would the designers/experimenters of those days think of the tools we have now? In that section, Zaic admits the lack of knowledge due to experience with a FW planform. They buillt, tested, observed and modified until a plane was stable. At least we can save crashes, money, and lives with our new tools... usually.
Dihedral is used (primarily) to make unstable models/airdcraft fly in the hands of a mere mortal.
In early days, the dihedral was used to compensate for semi free-flight, radio guided models..but with todays tech, and some exprerience, you want to replicate some of the handling of the original, or in the case of this wing....something else.
To explain....
Example 1: we have a high wing Telemaster type aircraft, all teh weight is below the wing, the wing is almost a sqr panel...so a small amount of dihedral makes the model pretty much fly itself....great for burgening AP pilots...
However, if you go waving the sticks around, it wil rock from wing to wing, the upshot of that is that it gives the pilot confidence, but if its trying to navigate, or your have a cam onboard, the rocking can be nasty, expecially for the up-chuck reflex...
example 2:
Flying wing...highly swept, so aerodynamically this is 'induced dihedral' so teh stability is already there, if you add physical dihedral, the wing would fly, but badly, and very rocky..back to the waving the sticks about thing...
In essence, the 40deg of sweep (or there abouts) is like putting say 3" per tip of dihedral in a panel wing...
Example 3:
EDF model Folland Gnat/Hunter/Harrier.......
Highley swept wings again, and due to the models (and teh real things configuration) this again creates 'induced dihedral' only this time, we need to put anhedral in the wing as the induced dihedral causes the rocking...
due to precession (and other forces), angle of wings (as in the angle they are presented to the airflow), and shape, we get dutch rolling.. as you know, the nasty effect of rolling from tip to tip, use of the ailerons only axecerbates the situation. (this killed a few Gnat pilots in the early days)
Point in case is that these aricraft/models stilll have to be flown by humans, so the configuration creates a very unstable situation (great for a fighter), so anhedral is then added to the wing to null some of the dutch rolling..and give control back to the pilot...
look at an F-4 Phantom.....this is a huge example of correcting the flight characteristics....dihedral tips, anhedral tails...all done to null one effect or another...
Oddly enough all the models of the F-104 starfighter we make with a scale wing, is probably one of the most stable platforms we have (difference between the model and the real thing... is the wing loading)
There is some very complex math which explains all this, but in short this is why we can use more scale options on our models, moreover, the gear we are flying with is fast and responsive, so once we have learned how to fly they configs, its very doable...
summet worth noting, is that in an FPV ship...the flater the wing the better....seen many an FPV pilot/drone operator turn green from teh designers mis-use of a particular wing. Fully understand the designers wish, to create the most stable ship he/she can, but in many cases, the conclusion is the oposite of what was planned.
I hope none of this was patronising, and that i have explained clearly enough.
It is a very visually striking design and would look fabulous in the air. The spacious cargo/electronics sections look to accomodate a large variety of options. I would love to add it to my stable of aircraft.
I have general questions about modern modeling. It seems of late that dihedral has been removed from most designs. Why so? My observations of every drawing, lately posted, seems to support this trend. Is it a simple decision based on ease of construction or manufacturing?
Mike, with your experience in the modelling business, perhaps you could shed some light on my dim confusion? My building/flying experiences started in the early 1970's. Please forgive a vintage modeller for perhaps missing something that may have changed in aeronautical engineering theory since then.
There was no damage at the plane after that. The OSD said the crash was with a speed of 80 km/h But the sign caught me not central, only on a wing.
But after the car chase i hit a tree with ~ 90km/h with the central blutnose. What large parts of damaged laminate ater that. After the Reperatur work I realized during the flight that the inner carbon rods were also damaged. As the Plane while plane dive swung and broke into 2 halves .
Comments
Mike, I sensed no patronizing at all and thank you for the time and examples. My courses in higher maths at times touched on fluid dynamics but the system that is an aircraft, and particularly a model aricraft, were never mentioned. I suspect much MatLab and Labview stuff exists to support the current design schemes.
This sidecar discussion would do for a fine separate topic as many modellers would benefit from the practical results from experiment/tests.
The flying wing design was discussed at length in the 1938 issue of "Model Glider Design" by Frank Zaic. Oh what would the designers/experimenters of those days think of the tools we have now? In that section, Zaic admits the lack of knowledge due to experience with a FW planform. They buillt, tested, observed and modified until a plane was stable. At least we can save crashes, money, and lives with our new tools... usually.
Thank you again for the informative answer.
-=Doug
Hi R.D,
Thank you for the kind words...
ok, dynamics...
Dihedral is used (primarily) to make unstable models/airdcraft fly in the hands of a mere mortal.
In early days, the dihedral was used to compensate for semi free-flight, radio guided models..but with todays tech, and some exprerience, you want to replicate some of the handling of the original, or in the case of this wing....something else.
To explain....
Example 1: we have a high wing Telemaster type aircraft, all teh weight is below the wing, the wing is almost a sqr panel...so a small amount of dihedral makes the model pretty much fly itself....great for burgening AP pilots...
However, if you go waving the sticks around, it wil rock from wing to wing, the upshot of that is that it gives the pilot confidence, but if its trying to navigate, or your have a cam onboard, the rocking can be nasty, expecially for the up-chuck reflex...
example 2:
Flying wing...highly swept, so aerodynamically this is 'induced dihedral' so teh stability is already there, if you add physical dihedral, the wing would fly, but badly, and very rocky..back to the waving the sticks about thing...
In essence, the 40deg of sweep (or there abouts) is like putting say 3" per tip of dihedral in a panel wing...
Example 3:
EDF model Folland Gnat/Hunter/Harrier.......
Highley swept wings again, and due to the models (and teh real things configuration) this again creates 'induced dihedral' only this time, we need to put anhedral in the wing as the induced dihedral causes the rocking...
due to precession (and other forces), angle of wings (as in the angle they are presented to the airflow), and shape, we get dutch rolling.. as you know, the nasty effect of rolling from tip to tip, use of the ailerons only axecerbates the situation. (this killed a few Gnat pilots in the early days)
Point in case is that these aricraft/models stilll have to be flown by humans, so the configuration creates a very unstable situation (great for a fighter), so anhedral is then added to the wing to null some of the dutch rolling..and give control back to the pilot...
look at an F-4 Phantom.....this is a huge example of correcting the flight characteristics....dihedral tips, anhedral tails...all done to null one effect or another...
Oddly enough all the models of the F-104 starfighter we make with a scale wing, is probably one of the most stable platforms we have (difference between the model and the real thing... is the wing loading)
There is some very complex math which explains all this, but in short this is why we can use more scale options on our models, moreover, the gear we are flying with is fast and responsive, so once we have learned how to fly they configs, its very doable...
summet worth noting, is that in an FPV ship...the flater the wing the better....seen many an FPV pilot/drone operator turn green from teh designers mis-use of a particular wing. Fully understand the designers wish, to create the most stable ship he/she can, but in many cases, the conclusion is the oposite of what was planned.
I hope none of this was patronising, and that i have explained clearly enough.
Kind regards,
Mike.
It is a very visually striking design and would look fabulous in the air. The spacious cargo/electronics sections look to accomodate a large variety of options. I would love to add it to my stable of aircraft.
I have general questions about modern modeling. It seems of late that dihedral has been removed from most designs. Why so? My observations of every drawing, lately posted, seems to support this trend. Is it a simple decision based on ease of construction or manufacturing?
Mike, with your experience in the modelling business, perhaps you could shed some light on my dim confusion? My building/flying experiences started in the early 1970's. Please forgive a vintage modeller for perhaps missing something that may have changed in aeronautical engineering theory since then.
HI Guys,
Well here it is...
not quite done, but ready to evaluate what need to go in her..
Thoughts?
Kind regards,
Mike.
we have been manufacturing Rc models for 12 years. (amongst many other things)
Will do my best to make her ruggid!
trouble is you have the BEST scenery, hard to get anything close to that..
But, we have to try! :)
I cant wait to be honest, i will post the renderigns here when done (assuming you guys are interested)
regards,
Mike.
Nice, i hope you will make your plane as stable as mine. X8 locks a little bit easy to destroy for me.
Hi guys,
I have to be honest, i do have a business designing and manufacturing RC models, BUT i have not used the video for this purpose.
I also have my own flying club, if you will, and we are all a bunch of middle aged kids, this vid has lit a fire under all our FPV guys,
(Please feel free to check the link to make sure its ok with you YOUR VID USED ON OUR SITE )
I have now got the Flying wing bug so now designing one up in SW for manufacturing.
so impressed with what you have done...we have to have a go.
Hope this is ok with you.
(for those interested it will look like a bit like an X8 when done)
sorry to hijack the thread, just wanted to be completely transparent with you.
kind regards.
Mike.
Flying wings are just the coolest things out.
Thx.
There was no damage at the plane after that.
The OSD said the crash was with a speed of 80 km/h
But the sign caught me not central, only on a wing.
But after the car chase i hit a tree with ~ 90km/h with the central blutnose. What large parts of damaged laminate ater that.
After the Reperatur work I realized during the flight that the inner carbon rods were also damaged.
As the Plane while plane dive swung and broke into 2 halves .
Great video. The chase car / car chase was really cool. How much damage did it cause when you hit the sign?
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