Newbie here, still learning how to fly and having to buy new propellers. Of the various properties to be chosen among, there are two that have me a bit baffled:
- symmetrical vs. undercambered
- swept-tipped vs. straight-tipped
Looking at pictures of historical aeroplane propellers (my model is a Piper Cub, the original of which was first flown in 1938), there only seems to be the symmetrical+straight variant:
So when did undercambered, swept-tipped propellers come up, what were designers trying to achieve with them, and what are their advantages and disadvantages?
Here's an example of a prop sold by a popular Hongkong-based brand:
As another example, the model I'm learning with came with an APC 7x5E prop, which has these two properties even more pronounced:
(Full disclosure: this question evolved from that one over on Aviation.SE where I was told I'm off-topic and lacking focus and to go here instead. Please let me know if either is still a problem!)