Japanese W II RC Models

[blackkite]

Hi! Enjoy.http://www.youtube.com/watch?v=quDLapk0a7k

 

[blackkite]

Next Ki-94-Ⅰ RC model flight movie.


http://www.youtube.com/watch?v=6E_P0V3vYDI

 

[Pelzig]

If my Japanese is correct, when the Ki-94-I was rejected, Tachikawa "repackaged" the design by beefing up the weapon fit and changing the role from high altitude fighter to a medium altitude heavy fighter with the designation Ki-104.

 

[blackkite]

Hi!
http://www.youtube.com/watch?v=gRrN7JNDnQo

 

[blackkite]

Next video.
http://www.youtube.com/watch?v=z-Bd9KWkKEU

 

[Stargazer]

Splendid!!

 

[Jemiba]

Great model ! And it shows (at around 3:19), that tail clearance of this type is quite low and
a bumper a necessity !

 

[blackkite]

According to this factory drawing, angle of attack was limited 9° to 10°30 when take off and landing. You can see pressurized cabin area in this drawing,too.
Great RC model indeed! She has 7 cylinders air cooling radial engines!!

 

[hesham]

Excellent my dear Blackkite.

 

[hartmutbehrendt]

Hello, the following for some interessest:
Josef has built this plane by using plywood, spruce stringer, balsawood, glass- and carbon fibre, and a lot of styropor. He has prepared a huge number of moulds to fabricate all the cfc parts.
The front engine is a Seidel ST 710, the rear one a Seidel ST 7-70.
Menz propeller at front 22/12, rear Menz 22/12 L, static RPM on ground 5200 RPM.
Wingspan 300 cm, Length 265 cm, dry weight 23.5 kg, No lead required for balancing.
Functions: elevator, rudder, aileron, jointly and separately controlled engines, 4 split flaps as landing aid, proportional pneumatic brakes, retractable landing gear specially made at Wabo, 8 cooling flaps for front engine (servo operated), electrically operated canopy, 2 indipendend glowplug electronic systems, for each engine one, made at Microsens, 17 servos, Futaba S-Bus servo wiring.
Plans increased three-side-view from internet. His drawn out detailed designs on this plans are not clearly visible and understandable, and so not suitable for publication.
Josef will never sell this model.
Regards, Hartmut

 

[Jemiba]

Welcome here Hartmut and thanks for those explanations. Yes, Josefs model is more,
than just an oob "Schaumwaffel" (foam wafer, fully depron models and the like) and it's
good staged by you, too. Always "Hals- und Beinbruch" for him as his model (Or are there
other greetings in the model scene ?) !

 

[thonthon42]

Hello, the following for some interessest:
Josef has built this plane by using plywood, spruce stringer, balsawood, glass- and carbon fibre, and a lot of styropor. He has prepared a huge number of moulds to fabricate all the cfc parts.
The front engine is a Seidel ST 710, the rear one a Seidel ST 7-70.
Menz propeller at front 22/12, rear Menz 22/12 L, static RPM on ground 5200 RPM.
Wingspan 300 cm, Length 265 cm, dry weight 23.5 kg, No lead required for balancing.
Functions: elevator, rudder, aileron, jointly and separately controlled engines, 4 split flaps as landing aid, proportional pneumatic brakes, retractable landing gear specially made at Wabo, 8 cooling flaps for front engine (servo operated), electrically operated canopy, 2 indipendend glowplug electronic systems, for each engine one, made at Microsens, 17 servos, Futaba S-Bus servo wiring.
Plans increased three-side-view from internet. His drawn out detailed designs on this plans are not clearly visible and understandable, and so not suitable for publication.
Josef will never sell this model.
Regards, Hartmut

Fantastic ! What else ?..

Tonton

 

[blackkite]

Hello, the following for some interessest:
Josef has built this plane by using plywood, spruce stringer, balsawood, glass- and carbon fibre, and a lot of styropor. He has prepared a huge number of moulds to fabricate all the cfc parts.
The front engine is a Seidel ST 710, the rear one a Seidel ST 7-70.
Menz propeller at front 22/12, rear Menz 22/12 L, static RPM on ground 5200 RPM.
Wingspan 300 cm, Length 265 cm, dry weight 23.5 kg, No lead required for balancing.
Functions: elevator, rudder, aileron, jointly and separately controlled engines, 4 split flaps as landing aid, proportional pneumatic brakes, retractable landing gear specially made at Wabo, 8 cooling flaps for front engine (servo operated), electrically operated canopy, 2 indipendend glowplug electronic systems, for each engine one, made at Microsens, 17 servos, Futaba S-Bus servo wiring.
Plans increased three-side-view from internet. His drawn out detailed designs on this plans are not clearly visible and understandable, and so not suitable for publication.
Josef will never sell this model.
Regards, Hartmut

Thanks for detail information. Really outstanding exact shape RC model.
Please ask Josef to build other Japanese beauties. For example, Ki-94-Ⅱ, Senden, Ki-98, etc.

 

[hartmutbehrendt]

Hello, there is one other japanese model of Josef 'in the tube', indeed: A huge 'SHINDEN. Engine runups and taxi trials are already done. Here at first some pictures. I will ask Josef if he allowes me to upload the video from the trials. If yes, you will find the video in 'YouTube' aswell. Regards, Hartmut

 

[hartmutbehrendt]

Welcome here Hartmut and thanks for those explanations. Yes, Josefs model is more,
than just an oob "Schaumwaffel" (foam wafer, fully depron models and the like) and it's
good staged by you, too. Always "Hals- und Beinbruch" for him as his model (Or are there
other greetings in the model scene ?) !

In the flying world we say 'Holm- und Rippenbruch', which means 'spar and rib fracture', Hartmut

 

[Jemiba]

A

In the flying world we say 'Holm- und Rippenbruch', ...

Ah, ok ! It will be the model that is hurt, not the pilot in most cases !

 

[blackkite]

Oh Josef did it!!!!!! Be careful in take off.
http://www.youtube.com/watch?v=CQR3VsbAf_c

 

[hartmutbehrendt]

:'(Hi Blackkite, Josef and me we know this video already, thank you. We are thinking about the circumstances for the crash. This video is the reason that Josef has delayed the first flight of his Shinden. He plans to built a smaller Shinden first to try the behavior. I myself I think that the area before the CG, seen from the side view, is greater than the area behind, the crash shows typical indizes for this matter, Hartmut

 

[Jemiba]

..the area before the CG, seen from the side view, is greater than the area behind, ..

Wouldn't this just result in a dive ? But the model obvious flipped inverted.

 

[blackkite]

:'(Hi Blackkite, Josef and me we know this video already, thank you. We are thinking about the circumstances for the crash. This video is the reason that josef has delayed the first flight of his Shinden. He plans to built a smaller Shinden first to try the behavior. I myself I think that the area before the CG, seen from the side view, is greater than the area behind, the crash showes typical indizes for this matter, Hartmut

Oh clever approach! Good luck to you.

 

[hartmutbehrendt]

Hello Jemiba,
I don't mean nose heavy around the transverse axis: If the Square meter before the CG is higher than after the CG, seen from the side of the model, the vertical stabilization around the vertical axis failes. The plane looses the direction, and while the airstream comes more and more from the side, the wing will swing up or down immediately and turns the whole plane to be inverted. I know this already because I had a model with this situation. The model did roll so quickly I could'nt even react at all.

 

[blackkite]

I imagine that,
Excessive pull up after take off ⇒Front wing stall because of high angle of attack ⇒ Lost front wing lift ⇒ Nose down ⇒ Dive ⇒ Crush
Should the model airplane be raised little by little?

http://www.youtube.com/watch?v=zZEaxlXtKGQ

 

[Jemiba]

...If the Square meter before the CG is higher than after the CG, seen from the side of the model, the vertical stabilization around the vertical axis failes.

Ok, think I got it now. Even slight disturbances are enough then for losing conrol. Somewhat glad, that I'm flying
"Schaumwaffeln" at best. Couldn't stand losing such a model ! :-\

 

[blackkite]

Hi! Finally right roll by propeller torque.

 

[blackkite]

The scene of touchdown of a model airplane was cut by edit in this video.
When watch the model airplane after landing, we realize that the door of a front wheel and a front wheel were damaged.
I imagine that the model airplane carried out hard landing by rapid nose down.
If this model airplane's angle of attack becomes large at a low speed, front wing stall and generate rapid head lowering occur this airplane? Didn't the IJN(Kugisho) know this tendency through the flight of MXY-6?
http://www.youtube.com/watch?v=zZEaxlXtKGQ

 

[blackkite]

Hi!
http://www.rcgroups.com/forums/showthread.php?t=642695&page=13

 

[blackkite]

Shinden front wing had retractable leading edge slat and double flap/elevator.
Shinden's main wing was made by thick plate with welded stiffner (without small rib).

 

[Jemiba]

If this model airplane's angle of attack becomes large at a low speed, front wing stall and generate rapid head lowering occur this airplane?

That's what principally makes a canard layout unstallable. At least the worst consequence, that can hapen to a conventional
aircraft, just plunging down tail first, cannot happen, as it would drop the nose and gather speed again. Of course that doesn't
mean totally vice free flying characteristics. :-\

 

[Bill Walker]

This depends on your definition of "stall". The main wing of a canard design is hard (but not impossible) to stall. The aircraft may have rotational momentum in the pitch axis at the time the foreplane stalls, allowing it to continue briefly pitching nose up, enough to stall the main wing.

Stalling the foreplane can result in a loss of pitch control that can only be overcome by changing the pitch. This is a bad situation to be in. You hope that the stall of the foreplane is accompanied by a nose drop, but it may not always be so, or it may not always be fast enough, or it may be too fast. Also note that if the nose pitches down to unstall the foreplane you are also reducing the lift coefficient of the main wing, at a time when you may not want to do this. Consider a foreplane stall on short final. An uncontrolled nose drop plus a loss of lift is probably not a good thing at that point.

I suspect this is part of the reason for the slats and double flaps on the Shinden canard. Stalling the foreplane before the mainplane is not desirable.

 

[blackkite]

This depends on your definition of "stall". The main wing of a canard design is hard (but not impossible) to stall. The aircraft may have rotational momentum in the pitch axis at the time the foreplane stalls, allowing it to continue briefly pitching nose up, enough to stall the main wing.

Stalling the foreplane can result in a loss of pitch control that can only be overcome by changing the pitch. This is a bad situation to be in. You hope that the stall of the foreplane is accompanied by a nose drop, but it may not always be so, or it may not always be fast enough, or it may be too fast. Also note that if the nose pitches down to unstall the foreplane you are also reducing the lift coefficient of the main wing, at a time when you may not want to do this. Consider a foreplane stall on short final. An uncontrolled nose drop plus a loss of lift is probably not a good thing at that point.

I suspect this is part of the reason for the slats and double flaps on the Shinden canard. Stalling the foreplane before the mainplane is not desirable.

Thanks a lot. Your explanation is little hard for me. I need more study about canard aircraft flight chracteristic.
Please show me your opinion about the reason why one Shinden RC model failed to take off and Japanese Shinden RC model failed soft landing.
The reason for take off failure was the posion of C.G.?
http://adamone.rchomepage.com/cg_canard.htm

 

[Bill Walker]

Blackkite, there are many reasons why an airplane will not takeoff or why an airplane will have a hard landing. It may not be anything to do with canards, "normal" airplanes sometimes have these problems too. Different c.g positions may need different pitching power to take off or land softly, so it may be a bad combination of pitching power (ability to raise or lower the nose) and c.g.

The c.g. calculator you show is a little simplified, but a good start. It seems to assume that both wings have the same CL curve, and the same zero CL angle of attack. The Shinden, with the slat and double flaps on the canard, can have very different aerodynamic characteristics on the front and rear wings. The calculations become a bit more complicated then.

 

[blackkite]

Many thanks again!

 

[perttime]

From what I've read on R/C forums, canard models can be very sensitive to CG location. They can fly very well but you have to get the setup right.

 

[blackkite]

From what I've read on R/C forums, canard models can be very sensitive to CG location. They can fly very well but you have to get the setup right.

Thanks! Japanese Shinden simplified RC model operator said so.
墜落 means crush. The operator said in this video that when C.G. shifted forward direction, crush.
http://www.youtube.com/watch?v=Stxn9FHjxvc

 

[blackkite]

Hi!
http://www.youtube.com/watch?v=5LCQ38BMExQ

 

[Jemiba]

"Fugaku still attacking !" ;D

 

[blackkite]

"Fugaku still attacking !" ;D

 

[Jemiba]

Sorry for that, was just a joke ! On the positive side, all models participating in that accident
were still with their owners, so they could be repaired. On an RC airshow with foatplanes, I once
witnessed a crash into the water and that model had gone forever, as even a diver couldn't find
the remains of it !

 

[ArgyrisGiannetakis]

I'm so glad to be here and see this Huge SHINDEN BUILD!!Congratulation to Mr Josef!!This shinden is impressive!!!Woww!!
I am so happy to be here and can answer about my SHINDEN NO1 and my new Shinden j7w1 THE RETURN.
I will send you some photos with the reason of crush and then my new all glass build about Shinden!
The reason of crush was the deferential of two canard elavators when i put all the move in take of.But also the little heavier front CG!
In canard the more front CG is like a more rear CG in conventional aircraft.
In my new Shinden i build more simple the canard.
Also i will build it all glass from molds ,so i have the chance to make all the test without stress!! ;D ;D
I'm sure that Mr Josefs Shinden will be fly great because he is GREAT BUILDER!!!Tachikawa KI 94 IS IS AWESOME!!

 

[ArgyrisGiannetakis]

Here is the one reason!!I also discovered when i zoom the photo!