Got some information from operational manual about early Ki-51 variant. Here is some additional information:
Te-4 ammo capacity:
For recon variant - 544 rounds (68x8)
For attacker variant - 1020 rounds (68x15)
Picture showing the layout of armor
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About weights here is tabled from manuals but I can’t understand it fully, maybe someone will understand it
As it is said at book, 250kg bomb was field modification what could be easy to do. So I think not only late variant could take it and this bomb can be used for all variants.
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Fuel tanks location. Total fuel capacity - 608 L
Interesting fact about bomb racks - it had the system that after bombs dropping to removes into the wing what reduce total Cx.
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The most interesting - the possibility to use additional bombs.
In reality it could use 2 additional rails for 1 50kg or 2 15kg bombs per each. But it is said that this rails used only when Ki-51 equipped with skies.
Even with this I think it can use x6 50kg but not x16 15kg.
Argumentation:
Here is no words that this pylons can’t be attached with simple bomb racks and the only question is with electro connection to the racks, here is scheme
As can be seen, the bomb “computer” can control and drop 12 bombs, 6 per each wing
And interesting that 4 additional 15kg bombs is written as “5, 6, 11, 12” what repeat numbers from standart load. So it shows that it can take maximum 12 bombs and additional one take place of standart.
But for 2 additional 50kg bombs it is written as “5, 6” while standart is “1 - 4”. Remembering that it can take up to 12 bombs, connection of 6 50kg looks real and I believe all variants could take up to 6 50kg bombs even at not skies configuration.
As it was said probable total bomb load: x6 50kg
And this scheme shows the bomb release sequence
Sources:
Magazine Maru, ed. 1999. “Type 99 Assault” Mechanism of Military Aircraft.
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Manual for operating Type 99, Army reconnaissance and Type 99 Army assault plane (изменено)
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