Reinhard Heidrich does over 50 slash attacks in no more than a tenth of a millisecond. In reality its 1/100th of a microsecond in the original japanese version. So I will use that timeframe
According to Filflourine, Heidrich is 190-200 centimeters.
this wiki says he is 192 centimeters. I will use that for his height
Reinhard = 404 pixels = 192 centimeters
Arm Side A = 78 pixels =
Arm Side B = 117 pixels =
Arm Length = 140.62 pixels = 66.8293 centimeters
Now according to Lina, since these are slashes, the distance is 1/3rd the circumference of a circle. The radius of this "circle" would be 66.8293 centimeters.
https://www.calculatorsoup.com/calculators/geometry-plane/circle.php
Plugging it in, the circumference is 419.9008758491 centimeters, and since he swung/slashed, it is 1/3rd of this. So each slash was 139.967 centimeters
He did 50 slashes
139.967 centimetersm * 50 = 69.9835 meters
69.9835 meters/00.1 microseconds = Mach 20,565,840.9 (23.3439829c)
Congratulations, your nazis are FTL+