B-17 Pilots Manual.pdf

switches are connected in parallel so that eitherswitch can be used to fire the guns. Deadman switches,one on each grip, are connected in parallel so that thegunner can operate the turret when either hand restson a grip. The deadman switch is provided so that thepower circuits of the turret will be opened and all turretmotion and firing of guns will be stopped when thegunner's hands are removed from the grips.!., Place sight switch in "ON" position.g. Close deadman switches on handgrips.!!.. Check response of azimuth and elevation mechanismsby manipulating the handgrips.1 Turn range knob and observe that reticles movein response.1 Adjust reticle light to approximately the desiredbrilliance.3. TURRET OPERATION.~. Charge guns by pulling each handle twice.g. Turn on gun selector switches.~. When target is sighted, set in target dimensionon sight.Q. Turn hand controls so that reticles frame thetarget..!!.. Adjust range knob until reticles frame the target.f. Press either firing switch.g. After ammunition has been used, charge gunsat least twice to clear out live shells.KEY TO FIGURE 51I. RANGEKNOB 5.2. TROUBLELIGHTSWITCH6.3. TROUBLELIGHT 7.ij. HANDGRIP 8.DEADMANSWITCHOXYGENFLOW CONTROLOXYGENMASK FITTINGELEVATION HANDCRANK!!.. When the turret is not being used, turn it so that ithe guns point aft and are parallel to the center line ofthe airplane.1 In event of power failure, the turret may be controlledby the azimuth and elevation hand cranks. Itis not possible to track a target with the hand cranks,but they may be used for approximate positioning pfthe turret and guns.İ1 To use the hand cranks:Figure 51 - Upper Turret Interior2. PREFLIGHT CHECK.~~~I Gun'M.ster .JSWItcha. Allow hydraulic units and sight to warm up atleast 5 minutes before take-off.g. Engage power clutches.c. See that hand cranks are disengaged. (Do notdisengage until after power clutches have been engaged.)~. Feed ammunition just up to the guns..!!,. Move main gun switch to "ON" position.Figure 52 - Upper Turret Switches60