Human powered cranes are quite common, in sizes up to a ton or two.[1] Most large auto shops will have one sized for engine removal. Overhead rail and chain fall systems are common.
The biggest hand-cranked crane-like devices ever built were probably the Panama Canal emergency dams.[2] This was a backup system in case a ship damaged all three gates of the top locks and let the lake pour through. The emergency dam could stop that.
It was a swing bridge long enough to swing across the canal, and although it could be operated electrically, it was also hand-crankable. This was regularly tested. The bridge was cranked out across the canal, above the water. Then wicket girder assemblies were cranked down into the water until they locked into slots in the lock floor. Then, one at a time, metal plates were dropped down tracks in the wicket girders, each one blocking more water, until all the plates were in place and the flow stopped.
They were never needed, and were dismantled decades ago.
Way back in the late 80's/early 90's I visited the USS Intrepid, a WW II carrier converted into a floating museum in Manhattan (to those in NYC: if it's still there it's well worth the visit).
Anyway, one of the (many) things that really impressed me was how easy it was to move the multi-ton antiaircraft gun turrets with just a hand wheel. Mechanical advantage FTW!
The biggest hand-cranked crane-like devices ever built were probably the Panama Canal emergency dams.[2] This was a backup system in case a ship damaged all three gates of the top locks and let the lake pour through. The emergency dam could stop that.
It was a swing bridge long enough to swing across the canal, and although it could be operated electrically, it was also hand-crankable. This was regularly tested. The bridge was cranked out across the canal, above the water. Then wicket girder assemblies were cranked down into the water until they locked into slots in the lock floor. Then, one at a time, metal plates were dropped down tracks in the wicket girders, each one blocking more water, until all the plates were in place and the flow stopped.
They were never needed, and were dismantled decades ago.
[1] http://www.northerntool.com/shop/tools/category_material-han... [2] http://engineering.dartmouth.edu/magazine/inventions-panama-...