6. Petlyakov PE-2 (USSR)
The Petlyakov PE-2 was a Soviet twin-engined light bomber that was built in great numbers during WWII due to its success. It is considered by many histories to be the best ground attack aircraft as well as a recon plane. It paralleled the German Junkers Ju-8 and the British Wellington and was fourth in number of productions, i.e. 11,427.
The bomber had a service ceiling of 8.800 meter and a max speed of 580 km/h. They could climb at a rate of 7.2 m/s making them highly effective in close encounters. In addition to delivering over 8 tons of bombs, they were fixed with machine guns which came in very handy as these planes were used as both bombers and fighters in changing situations.