Mitsubishi B-9 airfoil aka Blackburn B-9 airfoil seems to have been adopted by many Mitsubishi planes like B2M, G3M, Ki-15 and Ki-51.
Max wing thickness is known 16%.
If this G3M drawing is correct, position looks 30%.
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Mitsubishi B-9 airfoil aka Blackburn B-9 airfoil seems to have been adopted by many Mitsubishi planes like B2M, G3M, Ki-15 and Ki-51.Shinpachi-san,
Do you have any information the Mitsubishi B-9 airfoil, used on the Ki-51 (and I think the Ki-21)?
Mitsubishi B-9 airfoil aka Blackburn B-9 airfoil seems to have been adopted by many Mitsubishi planes like B2M, G3M, Ki-15 and Ki-51.
Max wing thickness is known 16%.
If this G3M drawing is correct, position looks 30%.
View attachment 737027View attachment 737028
I only traced the drawing
I only traced the drawing
0 0
1.25 2.055
2.5 3.115
5 4.735
10 7.010
20 9.255
30 9.935
40 9.710
50 8.925
60 7.735
70 6.195
80 4.375
90 2.320
100 0
90 -1.345
80 -2.520
70 -3.570
60 -4.510
50 -5.345
40 -5.955
30 -6.220
20 -6.020
10 -4.980
5 -3.855
2.5 -2.895
1.25 -2.125
0 0
The designer for Kawanishi was influenced by Shorts flying boats to modify airfoils.
?influenced
Yes, they had?
Was there co operation between Short and Japan?
To add to that...
The connection between the British Royal Navy and the Japanese was long standing, the only surviving pre dreadnought battleship in the world was built by the British at Barrow for the Japanese being laid down in 1899. Japanese battleship Mikasa - WikipediaAhh the spying game. The un wanted co operation game.
Thievery is i think not co operation but all sides did I suppose. Still do. No shame in that.
I have traced drawings as no more clues.The designer for Kawanishi was influenced by Shorts flying boats to modify airfoils.
No codes for them are found so far.
I have traced drawings as no more clues.
Kawanishi H6K
0 0
1.25 2.48
2.5 3.43
5 4.74
10 6.63
20 8.91
30 9.69
40 9.81
50 9.23
60 8.11
70 6.56
80 4.69
90 2.50
100 0
90 -1.31
80 -2.61
70 -3.80
60 -4.80
50 -5.58
40 -6.10
30 -6.23
20 -5.90
10 -5.10
5 -3.93
2.5 -2.94
1.25 -2.14
0 0
Kawanishi H8K
0 0
1.25 2.98
2.5 3.97
5 5.35
10 7.23
20 9.48
30 10.69
40 10.96
50 10.37
60 9.17
70 7.44
80 5.33
90 2.86
100 0
90 -0.74
80 -1.72
70 -2.77
60 -3.78
50 -4.69
40 -5.43
30 -5.91
20 -5.94
10 -4.95
5 -3.74
2.5 -2.72
1.25 -1.94
0 0
View attachment 737530View attachment 737531
Good job Sir!Here is what I found:
The Kawanishi H6K root airfoil appears to be a NACA (1.8)516 (a NACA 2416 with camber reduced from 2% to 1.8%)
View attachment 737545
The Kawanishi H8K root airfoil appears to be a NACA (2.7)516.6 (a NACA 3516 with camber reduced from 3% to 2.7% and thickness increased from 16% to 16.6%)
View attachment 737546
Based on those coordinates, the Mitsubishi 118 is a NACA 250 mean line, with max camber at 25% chord, instead of 15% chord, as with 230 mean line ( see NACA report 537 ). The camber is reduced to 2%, from 2.3% for the standard 250 mean line ( the value of k is about 2.858 vs the standard value of 3.23 ). The NACA designation would be something like 250xx modWas it really that thick at the root?
View attachment 737338
Comparing this to the 23015 that is sometimes given for the zero provides a poor match;
View attachment 737339
A 15014 gives the best 5-digit match I could manage;
View attachment 737340
But a 2314 looks closer still. Maybe the sources that say 23015 mistook a 4-digit for a 5?
View attachment 737341