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ctsdesign
19-Feb-10, 11:56 AM
Has anyone got any iformation on the hasconwing sickle blades, I read a thread from awhile ago about the sickle blades but I can't find any info on them, or a picture at that matter, anyone got anything?

ctsdesign
19-Feb-10, 12:07 PM
I see that multi-wing sells a sickle blade has anyone ever tried these on a craft, how do they perform? and how would you set up a stator in the duct to these diffrent blades?

campbe5177
19-Feb-10, 01:01 PM
Try Keith at Vortex Hovercraft. He brought a craft with them on The Rhone Raid last year.

Keith Oakley
19-Feb-10, 02:31 PM
Keith Smallwood and I have been looking at them for over a year. Its still work in progress but lets say the performance results aren't stunning, thrust is less than 5Z, they're heavier and more expensive. They may be a way to a quieter craft but latest results suggest by learning lessons with the 1W sickle we can get similar results with a suitable setup on 5Zs. Ideally the stators for them are a complex double curve shape. I'd stay with 5Z for the moment.
Keith Oakley

gavinparson
20-Feb-10, 06:41 AM
As Keith said, they're still being evaluated and in theory should be quieter.But from what I saw on the Rhone Raid last year (and have video to prove it), the craft with these blades was noisier than mine which was fitted with 5Zs.
Let's hope an ideal, efficient set up can be found for these blades or else the manufacturers come up with a profile that is actually quieter for hovercraft use.

smallw1449
21-Feb-10, 05:52 PM
Yes Gavin was right the craft was noisy on the Raid last summer, We had got the fan setup wrong and the 35hp Briggs was doing 4200rpm and so the fan was spinning way too fast and very ineffecient. Since then we have regeared, reset the fan to do the design speed of 1480rpm and it is now very quiet (sub 75dba). However,. noise may be low but so is performance, good lift but very minimal thrust.

On the subject of noise we are now producing craft with good performance (29hp Briggs) with 8/12 45deg slow running (approx 1500rpm) Hascon (5Z type) blades, noise is around 71dba when measured using the standard EC noise measurement method. You need to use 8 or 9 blades to absorb the power at these low revs and produce enough lift.


Keith Smallwood