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Posted by Owen Hedger | Sep 26, 2011 @ 06:20 AM | 3,649 Views
So after a year of being finished I can finally clean up the Ohka build on my blog page.

The Ohka has been flown and damaged beyond repair but it was a load of fun. It was incredibly tail heavy as expected. It made the launch tricky and was the down fall when the wind dropped off abruptly. The tail flew well and so did the plane when it had good airspeed.

Total flight time was 5 minutes and 44 seconds and well worth building it. I have already started planning a replacement with bigger roots and a bit less span which will hopefully be lighter and better balanced....Continue Reading
Posted by Owen Hedger | Apr 05, 2010 @ 06:15 AM | 4,815 Views


Started here:

http://www.rcgroups.com/forums/showthread.php?t=1205811

Update:

Got most of the foam glued in to the frame and cut. Installed all the servo wires to the tail and wings.

Installed tail platform and box for balance weight but the balance has me concerned. So far the fuse only 1000g and if I can make the tail 150g or less I will be very happy but it seems it going to take 600g or more of lead to get the balance right. Im going to extend the balance weight box forward another bulkhead to try and keep this under control. If that fails Im going to have to extend the wings a little.

It proving to be a challange modeling something that flew with 600kg bomb in the nose. I will know better how the weights going once I get the tail done so that is next.
Posted by Owen Hedger | Mar 21, 2010 @ 04:47 AM | 4,610 Views
Work over the last 2 week:

Cut litening holes in the bulkheads. Saved about 85 grams and can now run servo wires down the fuse with the greatest of ease.

Glued up the frame. Frame turned out to be fairly rigid.

Worked on the wingtubes. Got a dihedral angle im happy with (6 degrees).

Started to add the foam to the frame. Foam panels make the frame very rigid.

Built the wing frames.
Posted by Owen Hedger | Mar 07, 2010 @ 03:25 AM | 6,570 Views
Here we go with my build for the Manilla Slope Fest 2010 PSS.

My choice of aircraft? The Yokosuka MXY-7 Ohka Model 22. A Japanese suicide piloted glide bomb. By my account a fairly simple construction but impressive looking aircraft. Simple is good as this is my first plan-less scratch build of any description.



http://en.wikipedia.org/wiki/Ohka

I had originally been planning to do test version with a length of 1m with wings to match using the materials I had handy with plans to make a 2.0-2.6M wingspan version if the test version flew ok.

The test version has since been revised up to a length of 1.25M (1:5.5 Scale) with a 1.4M (subject to change) wingspan which may eliminate my desire for the larger version.

My approach to its construction is currently a stick and bulkhead frame with an outer shell of foam which will then be glassed if not balsa sheeted the glassed.

If I can bring it in under 2Kg AUW with a wingspan 1.4M my wing loading will be/under 27oz per square foot. Not a terrible loading thankfully but I fell it will be on the heavy side. My biggest concern is the balance weight that it will require. The model 22 was designed to carry a 600Kg bomb in the nose. I work that out to be 3.6Kg in 1:5.5 scale At least I will not have the 200Kg thrust microjet in the back end. Im hoping Desperately that 0.5kg will be the limit of the balance weight I need.

A span of 1.4M is actually almost double the span of a scale model 22. Iím basing my wing span on the model 43 which had a wing span 10% greater than the length of the aircraft.

And my parts so far dry fitted...