The internals of little viewing holes are sometime difficult to sometimes spot on walk about.........
The pressurisation on the 1900...does the aircraft have a manual dump valve so permitting the aircraft to pressurise while, eg, taxiing. In the other words, is the aircraft already partly pressurised before take off? Or, does it have the system of squat switches on the (usually left) oleo so that it only pressurises once the main gear is airborne and therefore after V1 Rotate? AIR this is the system of the B200.100.....?