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1/3 scale Japanese vintage glider Mita type 3

Let us all watch your new project progress.
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norm
Posts: 49
Joined: 14 Nov 2019, 10:15
Location: Utsunomiya,Japan
Contact:

Re: 1/3 scale Japanese vintage glider Mita type 3

Post by norm »

Horizontal Tail

Horizontal tail of the 1/3 Mita is a quite conventional one, made of balsa ribs and spars. The stabilizer is planked with balsa sheet. The elevator has diagonal ribs and is not planked. Right elevator has a dummy tab. Elevator hinges are made of carbon plate, acrylic plate and bamboo rods. Both stabilizer and elevator were build on the jigs.
Attachments
Horizontal Tail Plan
Horizontal Tail Plan
Elevator Jig
Elevator Jig
Elevator Parts
Elevator Parts
Elevator Completed
Elevator Completed
H-Stab. with Elev. Hinges
H-Stab. with Elev. Hinges
H-Tail Assy
H-Tail Assy
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norm
Posts: 49
Joined: 14 Nov 2019, 10:15
Location: Utsunomiya,Japan
Contact:

Re: 1/3 scale Japanese vintage glider Mita type 3

Post by norm »

Elevator Control Sys

The elevator control system of the original Mita is a linkage half by rods and the rest by wire. There are two bell cranks, one at the middle and the other at the end of the fuselage. Two rods connect the pilot sticks and the foward bell crank. Between the bell cranks there is a wire linkage and the elevator is connected to the aft bell crank by a connecting rod.

My 1/3 scale model simulates this system. A servo is placed under the aft pilot seat and connected to the linkage rod. Thus the control sticks moves for and aft in accordance with the elevator up and down.
Attachments
Elevator Control sys Drawing
Elevator Control sys Drawing
Stick Gimbals installed
Stick Gimbals installed
Elevator Servo and FWD Bell crank
Elevator Servo and FWD Bell crank
FWD Bell crank detail
FWD Bell crank detail
Wire linkage between bell cranks
Wire linkage between bell cranks
AFT Bell crank
AFT Bell crank
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norm
Posts: 49
Joined: 14 Nov 2019, 10:15
Location: Utsunomiya,Japan
Contact:

Re: 1/3 scale Japanese vintage glider Mita type 3

Post by norm »

Vertical Tail
The vertical tail of the Mita has similar structure with the horizontal one, planked fin and non-planked rudder with oblieque ribs. In the 1/3 model, these are all made of balsa except the fin spar which is made of cypress. The rudder has two hinges, mid and bottom, and it can be put on/off the fin easily. Both the fin and the rudder were assembled on jigs made of balsa.
Attachments
Vertical Tail Plan
Vertical Tail Plan
Fin Parts
Fin Parts
Rudder Parts
Rudder Parts
Rudder Assembling on a Jig
Rudder Assembling on a Jig
Fin assembled
Fin assembled
Rudder assembled
Rudder assembled
Vertical Tail Assembled
Vertical Tail Assembled
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norm
Posts: 49
Joined: 14 Nov 2019, 10:15
Location: Utsunomiya,Japan
Contact:

Re: 1/3 scale Japanese vintage glider Mita type 3

Post by norm »

Rudder Control Sys
The rudder control system has a conventional wire linkage. There are four turnbuckles, two in between the front and aft pedals and two in between the aft pedals and the rudder. I made these turnbuckles from 5 mm dia bruss rod. The pedals are made of bruss tubes. The rudder servo is placed just after the front pedals and is linked with them. It works as the pilot feet. Behind the servo there is an instrument panel, so the servo can't seen from outside.
Attachments
Rudder Control Sys DWG
Rudder Control Sys DWG
Rudder Pedals
Rudder Pedals
Front Pedals with Servo
Front Pedals with Servo
Aft Pedals with Turnbuckles
Aft Pedals with Turnbuckles
Aft Turnbucles
Aft Turnbucles
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MDev
Posts: 112
Joined: 07 Oct 2018, 19:17
Location: WEYMOUTH

Re: 1/3 scale Japanese vintage glider Mita type 3

Post by MDev »

I like the thinking behind this fuse structure, I’ve made a tail out of Airex and carbon sandwich glued with epoxy and sailing masts out of carbon tubes With jumper struts in a similar fashion, they’re holding together still after 15 years or so. I wonder how resilient the structure is and do landing forces pass through it to the built up wings? Time will tell.

M

norm
Posts: 49
Joined: 14 Nov 2019, 10:15
Location: Utsunomiya,Japan
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Re: 1/3 scale Japanese vintage glider Mita type 3

Post by norm »

Cliff, yes it is a pity for me too that I can't show you my model and fly it over the beautiful scenary of the U.K.
I have been in the U.K. several times and love the scenary of the Cotswalds best. How I hope my model flying over the gentle hills there!

norm
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norm
Posts: 49
Joined: 14 Nov 2019, 10:15
Location: Utsunomiya,Japan
Contact:

Re: 1/3 scale Japanese vintage glider Mita type 3

Post by norm »

MDev, thank you for your comment. It is interesting that there are many modelers who have interest in my carbon truss structure. I glued it with carbon filaments mixed epoxy and attatched a small carbon plate where the stress seems high.
Yes the landing loads may be the most severe one but they make compression at the truss joints. Epoxy glued joints are week for the bending or tension stress but they endure for compression stress much better. So far they look working well but, as you say, time will tell the truth.

norm
Last edited by norm on 27 Nov 2019, 02:28, edited 1 time in total.
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norm
Posts: 49
Joined: 14 Nov 2019, 10:15
Location: Utsunomiya,Japan
Contact:

Re: 1/3 scale Japanese vintage glider Mita type 3

Post by norm »

Aileron
The ailerons of the Mita are the frise type one. They also have a differential too. It was very time consuming task to design the rib contour because the base wing airfoils are defined parallel to the air flow, but the aileron ribs are placed diagonally to the wing span. If I could use the 3D CAD it would be easy task but because my CAD is 2D, it took time.

The ailerons have mass balances. I made them with aluminum tube and block. The real Mita's ailerons are linked with the sticks but in my model ailerons are linked with the servos placed in the wing, so the sticks are free laterally. I used a small dummy servo connected to the stick longitudinal shaft. It prevents the sticks from lateral free movement and moves them when the ailerons are moved.
Attachments
The Aileron DWG
The Aileron DWG
Finding the Aileron ribs contour
Finding the Aileron ribs contour
Aileron Cross section
Aileron Cross section
Aileron Controll Throw
Aileron Controll Throw
Aileron Controll and the Mass Balance
Aileron Controll and the Mass Balance
Aileron control rod and mass balance
Aileron control rod and mass balance
Aileron ASSY
Aileron ASSY
Dummy servo
Dummy servo
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User avatar
Peter Balcombe
Posts: 967
Joined: 18 Mar 2015, 10:13
Location: Clevedon, North Somerset, U.K.

Re: 1/3 scale Japanese vintage glider Mita type 3

Post by Peter Balcombe »

Norm,
Amazing attention to detail and very good engineering skills.
Very well done indeed.
Peter

norm
Posts: 49
Joined: 14 Nov 2019, 10:15
Location: Utsunomiya,Japan
Contact:

Re: 1/3 scale Japanese vintage glider Mita type 3

Post by norm »

Peter, Thank you for visiting my thread. I will post more details and hope you will enjoy them.

norm
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