And what country can preserve its liberties if their rulers are not warned from time to time that their people preserve the spirit of resistance? Let them take arms. The remedy is to set them right as to facts, pardon and pacify them. What signify a few lives lost in a century or two? The tree of liberty must be refreshed from time to time with the blood of patriots and tyrants.
I seem to remember reading somewhere that counter rotating was inefficient when the second blade was behind the first one. Must be one reason that we see examples in the world so rarely. Helicopters being an exception.
The engines on the Tu95 Bear generate 15,000hp each. If it had normal props they would have to be much larger in diameter to turn all that horsepower into thrust. This would require much taller landing gear to keep the props off the runway. Also you want to keep the prop tips below the speed of sound so the bigger props would have to turn slower which means the reduction gear box in the front of the engine would have to handle more torque as would the engine mounts and the firewall structure they are bolted onto. What I find amazing is the pitch angle on the blades. The faster you go the coarser the pitch angle you need to maintain effective pitch. Al_in_Ottawa
Contra rotating.
ReplyDeleteLooks like the TU-95 Bear. A Russian bomber about the same age as our B-52 and in service.
ReplyDeleteI think the Ukrainians blew up a couple of these with drones while they were on the ground reducing the number still flying.
Deleteiirc they were so loud, we could track them without radar, just sound detection
ReplyDeleteI seem to remember reading somewhere that counter rotating was inefficient when the second blade was behind the first one. Must be one reason that we see examples in the world so rarely. Helicopters being an exception.
ReplyDeleteContra, not counter.
DeleteEasy fix. Just put the second blade in front of the first one.
ReplyDeleteNow that's a hoot!
DeleteSnork!
DeleteThe engines on the Tu95 Bear generate 15,000hp each. If it had normal props they would have to be much larger in diameter to turn all that horsepower into thrust. This would require much taller landing gear to keep the props off the runway. Also you want to keep the prop tips below the speed of sound so the bigger props would have to turn slower which means the reduction gear box in the front of the engine would have to handle more torque as would the engine mounts and the firewall structure they are bolted onto.
ReplyDeleteWhat I find amazing is the pitch angle on the blades. The faster you go the coarser the pitch angle you need to maintain effective pitch.
Al_in_Ottawa
Is the film running in reverse, or is this air-braking after landing?
ReplyDeleteMy guess, this is the notorious video artefact, also the cause of rubber safety propellers.
Delete