... what three Army aircraft? ___ A. UH-1H, AH-1S, and OV-1B. ___ B. UH-1D, AH-1H, and OV -1. ___ C. OV-1A, AH-1G, and UH-1E. ___ D. OV -1, AH-1G, and UH-1C. 4. What type of pump is often used ... the system. Figure 1- 4. Double-Action Hand Pump. 6 AL0926 charge, filling the upper chamber with fluid pressure. The broken lines in Figure 1- 11 indicate the approximate ... In B, Figure 2 -11 , the ratchet valve is shown with pressure applied to port 1. This forces the piston to the right where it unseats ball check valve b. Pressure entering port 1 also unseats...