KI-67 Update?

[BuckShot]

Perhaps pressure perpendicular to the gun slot will rotate the bubble.

[lyric1]

Perhaps pressure perpendicular to the gun slot will rotate the bubble.

The rear absolutely.  
The front I think has a combination barrel pressure & handles to help rotate. 

[lyric1]

Wheels off of a Ki-67 video.

https://www.youtube.com/watch?v=ClcZUfaenxg

[lyric1]

The question is now is this drawing with the nose gun arcs correct?

Found this on a Japanese site the gun arcs per this drawing don't match the above sketch.

The first block of text says 機首 銃座 = Nose Turret.
The remaining text for the nose gun says.

水平方向 = Horizontal direction.
垂直方向 = Vertical direction.
1時 = 1 o'clock
11時 = 11 o'clock



Little confused as to how this is applicable at the moment  Seems that depending what side of the slot the gun is in it will get 45 deg on one side & 50 deg on the other regardless of being horizontal or vertical.  That would make sense since the rails & the slot are offset in relation to the Plexiglas center.
Keep in mind the turret is on a ball bearing race that may have 360 deg rotation?


Took a clear protractor & tried lining up the gun mounting system that is shown with the yellow arrow in the first photo & that is shown again in the 2nd photo where the gun is not installed.
When you line up the mounting bracket in a free lying state it is at 45 deg with no one pushing it down & if you line up the hole in the Plexiglas where the barrel fits it looks to have 50 deg.

This new information seems close to what we should have rather than the first gun arc drawing.

[lyric1]

Little confused as to how this is applicable at the moment

I  think I get it now.   

 

[lyric1]

Couple of other observations I noticed for the rear gun.

回転風防 = Rotation windshield. No doubt now that the domes rotated. 

打殼入れ = Hit shells purse/Shell catch bag?




Can see the catch bag well in this photo.



Also a bag mounted on the front gun.

[lyric1]

From what I can see in the pictures, you have to do it. 

Found two interesting photos when you zoom in on the front gun these two images clearly show some kind of mechanical mechanism possibly attached to the outer metal rotating ring. I would say the nose turret drawing with the handles that clearly would have been rotated by hand & or the gun barrel is wrong .



First off here is a close up of the bracket that the gun pivoted on for horizontal & vertical movement on this wrecked KI-67. It is not attached to the outer turret ring at all.



I marked the bracket in the next image with yellow.



Here is the first image I mentioned.



The second.



The first image I marked in different colours so they will make sense in the second photo.
The yellow markings show the same bracket that is in yellow from the wrecked ki-67 but only half of it is visible in this photo.
The two red marked brackets that are either side of the gun are attached to a square plate that I marked in blue. 
Note also the slot the gun sits in is in its vertical position at this point in time.




The second photo all the parts I mentioned & colour coded are the same. Yet now the red brackets are turned to the aircraft's left 90 DEG & the square plate that is marked in blue is no longer at the very bottom.
Note the angle of the gun slot now? It is horizontal.




I think you would have to be a mechanical engineer to try & figure out how this front gun turret & all its moving parts work together without an original blueprint. 

The only line drawing I can find shows the bracket in yellow & only that. 








 

[lyric1]

From what I know of the gunners they just sat on a mat.

[morfiend]

Lyric,

   It makes sense that the plexi rotated independent of the gun and had it's own method to rotate,ie those handles!

   If the gun rotated the plexi then the gun would have to rotate and the gunsite would be all but useless. I was looking closely ay 1 of your early pix and it pretty much looked like the gun mount was fixed top and bottom to the plane,right where the part of the plexi that rotates.

  Those handles would need to be close at hand so the gunner could easily move it to the desired position to get the best range of motion for the type of attack he was trying to defend against.


  Atleast thats my take on it,great post!


     

[lyric1]

Lyric,

   It makes sense that the plexi rotated independent of the gun and had it's own method to rotate,ie those handles!

   If the gun rotated the plexi then the gun would have to rotate and the gunsite would be all but useless. I was looking closely ay 1 of your early pix and it pretty much looked like the gun mount was fixed top and bottom to the plane,right where the part of the plexi that rotates.

  Those handles would need to be close at hand so the gunner could easily move it to the desired position to get the best range of motion for the type of attack he was trying to defend against.


  Atleast thats my take on it,great post!


     

That was somewhat my thought's as well until this photo I found that I posted before. With the attachment brackets to the turret ring marked in blue & red. The yellow bracket is mounted at the top & bottom & pivoted left to right. I believe half way down the yellow coloured bracket is a pin that the gun was mounted with & allowed the up & down motion to take place by pivoting on that pin.









Also there is two somewhat different drawings of the Plexiglas turret one shows handles the other not.
What one is correct?








I think there maybe more to it but I can't tell for sure. The rail with the two movable Plexiglas inserts either side of the gun is the mystery & being offset from center  why? I think the center piece that the gun protrudes through along with the two inserts is all one part & the gun has to be what moves this piece inside of the rail system. Then with a pivot pin inside the yellow bracket & it pivots at the top and bottom from left to right all the weight & the motion of the gun is supported by the yellow bracket. Then a ball bearing mounted ring on the turret just pivots depending what way the gunner pushes the gun stock. The blue & red parts that clearly do attach to the turret ring is confusing to say the least.
They could have just done a slot like the rear gun with no rails a lot less complicated.





Four KI-67's were bought back to the USA at wars end & all are long scrapped.
I contacted the Smithsonian to see if any documents were saved I know the military did testing.
Usually takes about 6 weeks to get an answer.

 

[morfiend]

Looks to be a perplexing dilemma....


   If the gun is rotated wouldnt the gunsite rotate with it?

   If the gunsite is moved from 12 oclock to say 3 oclock or 90 degrees it would be useless IMHO. It looks to me like the gunmount is fixed to the inside ring and the plexi is connected with the bearing race to the outside of it.

  But I will bow to your experience and wait till you get any info from Smithsonia!



     

[BuckShot]

Maybe the barrel is mounted off center in the rear bubble so that movement from the barrel in any direction will more easily rotate the bubble, with the handles there in case it binds a little.

The front looks like the few degrees of travel where the barrel goes through the bubble is enough "off center force" to rotate the bubble where the rear needed to be asymmetrical to work right.

Great thread!

[lyric1]

Looks to be a perplexing dilemma....


   If the gun is rotated wouldnt the gunsite rotate with it?

   If the gunsite is moved from 12 oclock to say 3 oclock or 90 degrees it would be useless IMHO. It looks to me like the gunmount is fixed to the inside ring and the plexi is connected with the bearing race to the outside of it.

 


     

I see I didn't explain myself correctly from my previous post.  Because I am confused by your answer.

So lets look at the actual sights of the gun first.
The purple arrows show the sighting ring & the aiming point on the gun barrel. The light green arrow is the arm that holds the sighting ring. They did not have a heads up display type gun sight like we do in AHII.



Now the sighting ring and arm that holds the sighting ring it is not mounted on the actual gun at all. Its mounted on a cradle that the gun slides into.
You can see the cradle & sight ring in this picture that has yet to have a gun mounted in it.

Also this cradle is what pivots for the up & down motion of the gun. I painted an approximate location of the pivot point as it would be hidden from view in this image.



Now this cradle sits inside of the long rectangular yellow marked bracket with the radius on each end & it pivots at the top & bottom via a bearing & it gives the side to side motion.



From the gunners perspective with the right left arrows.



So the gun is fixed inside the cradle and has no ability at all to spin around like the HE-111 nose gun from the video I posted earlier in the thread. It can only pivot side to side & up & down.

So when the gunner has his shoulder on the stock he can rotate the gun in a circular motion up down left right & so on & so on.
The actual Plexiglas dome & it's metal ring is of course where the bearing race is located that is attached to the front of the fuselage.

The method of how the turret ring is moved is some how done I believe with the brackets marked in red & blue via the cradle & the motion of the gunner with the end of the stock of the gun.





How much motion the turret ring has in terms of degrees I don't know it may have 360 deg or less.

Now the rails on the dome are also on some kind of slide or a possible bearing surface as well.
As the gunner moves the gun & the outer turret bearing ring rotates it will also allow the slides to move in unison with the outer ring.  Or so I believe.


I found the same image from two different books showing a broken turret & it confirms the Plexiglas inserts that slide on the rail are one piece as you can see it hanging off the gun barrel.





Also you can see the same bracket that attaches to the bearing ring in red that I have shown before that controls the movement of the front turret. I think from now on I will call it the wishbone for obvious reasons.



I hope I did better a better job this time with how I think this works.

 




 

[lyric1]

Maybe the barrel is mounted off center in the rear bubble so that movement from the barrel in any direction will more easily rotate the bubble, with the handles there in case it binds a little.

The front looks like the few degrees of travel where the barrel goes through the bubble is enough "off center force" to rotate the bubble where the rear needed to be asymmetrical to work right.

Quite possible. 

[morfiend]

Lyric,

  for some reason I had it in my head that the gun was rotated,as opposed to being slewed{if that's the correct term}

   It's hard to see in the pix if the gunsite was on the mount or the gun so that's were I lost it,not you!

  I would agree the offset may help moving the plexi and allow the gunner that extra 5 degrees were he would benefit from it the most......  Maybe...

   I hope you get the info that clears this up,a simple yet complex thing,right up my alley!