Sikorsky Helicopters R-4B & HNS-1 Helicopters 1945 Pilot's Flight Operating Instructions (01-230HA-1) by Sikorsky Helicopters Sale $10.00 | / SKU 8135:R Printed Manual - $10.00 Download - $10.00 Printed Manual Download Size 1 2 3 4 5 6 7 8 9 10+ Quantity Quantity Add to cart