Forward Swept propeller

Member for

10 years 3 months

Posts: 6

I was reading about the scimitar propeller when it suddenly occur to me that, what if the propeller is forward swept? What's the advantage and the disadvantage. Sorry, i'm just aviation enthusiast and no expert in this things. So, any Gurus here can answer?
Original post

Member for

13 years

Posts: 8,826

It is modern technology making a prop more efficient, similar is the design of berp rotors on helicopters, you can only make a blade so long and you get problems with the tip speed reaching near supersonic speeds, so the profile allows a longer blade while reducing the effective speed at the tip. http://books.google.co.uk/books?id=nMV-TkaX-9cC&pg=PA303&lpg=PA303&dq=berp+rotors&source=bl&ots=Cp9Tf6YMey&sig=FmOkqN1WaqB73lWusBZ-3RGFvM8&hl=en&sa=X&ei=FfD5TqHMM5SzhAf085C9AQ&redir_esc=y#v=onepage&q=berp%20rotors&f=false The problem you have is as you are limited lengthwise to make use of the engine power you have to add more blade's hence late spits with 5 blades, but you then soon reach the max amount of blades you can add to the hub and increased solidity of the disc, contra rotating props get round that but you then have to offset the added weight... stuff like the older Herc uses short paddle blades but have wider chords so they look short but fat Another type which you rarely see these days is Q tips... These have the tips bent over about 90 degrees, mainly to reduce vortices at the tip and noise but they are rare..