How to install the B-17 propeller.

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That was pretty cool :+1:

I didn’t know those blades rotated for pitch, some crazy engineering

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I’ve been having trouble installing the prop on my B17
Thanks for posting.

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:rofl: :rofl: :rofl:

You do have to wonder if he was just reminiscing on his service days :face_with_hand_over_mouth:

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:grampa:

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My son worked on P-3’s so pretty cool for me to see. The P-3 has pretty big prop nuts by comparison.

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As I recall, the progression in technology was from fixed pitch props, to props that could have their pitch adjusted with a few tools while the engine was shut down, to props that had a manual control in the cockpit allowing the pilot to set the prop pitch (something of a rough control of blade angle), to the ‘constant speed’ props that added a mechanical prop governor to the previous system (allowed the pilot to set the governor to hold the engine at the chosen rpm by varying the blade angle as throttle setting and airspeed changed). That progression of technology occurred between World War 1 and the 1930s.

On multi-engine aircraft, the travel limit for blade angle went from a nearly flat pitch (leading edge of the blade 90 degrees from the front of the plane, to provide the least resistance to the engine spinning the prop), to a feathered position with the leading edge of the prop turned to the front of the plane (least wind resistance, if the engine failed in flight).

On the B-29s used for the atomic bombing missions against Japan, the ability to move the blade angle past a flat pitch, to a reverse pitch shifting the prop from pulling the plane forward to pushing it back, was added due to concerns that ground equipment might not be available to push the plane back over the pit that would be needed to load the atomic bomb. The feature became standard on the B-29D, which had its designation switched to B-50, to trick Congress into thinking the funding was for a new post-war design, rather than a continuation of war production to keep the atomic capability available until new jet bombers were through development and in production.

The reverse thrust capability allowed improved braking on landing, as the props could be shifted to reverse thrust to aid the brakes on the wheels. The reverse thrust capability was included on most turboprop planes that came later, but has rarely been included on piston engines, partly due to the disruption of cooling of the piston engine while the prop is in reverse mode.

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crazy to go from fixed to reverse, then of course to jet turbines, waiting for the magnets that are run off 9v :man_shrugging:

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There are companies working on developing planes that use electric motors, but from what I have seen so far, their estimates on how far their aircraft will be capable of flying seem to be not much better than guesses.

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