[Falcon]

Im sure it was for ventilation. See the difference to the G-series.

E/F-series:
- light plexi glass canopy
- sliding panels (top, left, right)
- the side triangle windows on the "Windschutzaufbau" can be open

G-series (unpressured):
- heavy glass canopy for more protection
- only left and right sliding panels
- fixed glass on the "Windschutzaufbau" side windows
Additional for better ventilation to get the E/F-series fresh air conditions:
- the vent openings left and right on the fuselage in the cockpit
- the small airscoops below the "Windschutzaufbau"