He 111V-11
The He 111V-11 was a prototype aircraft that began trials in July 1937. It was developed from a converted He 111B-1 bomber.
The primary purpose of the He 111V-11 was to test a new straight-edged wing shape, which underwent multiple modifications during trials. In terms of its design, all armament mountings were improved, and its Plexiglas nose dome was replaced with a hemispherical sheet metal cone.
The prototype was powered by DB 600CG engines and was otherwise identical to the D-1 variant. Its successful service trials were instrumental, leading to the production of the He 111F-1 series.