OT. Carbon Fibre NACA sections.

[Andy_P]

I am trying to get hold of some symmetrical NACA foil sections in carbon fibre. This is totally unrelated to aircraft, I want it for a sailing catamaran. Was kinda hoping some of the resident experimental people might be able to point me in the right direction. Think wing spar section, like what you find on a high wing aircraft, I want that in carbon fibre!

[Mechta]

Depending upon the size you want, model helicopter rotor blades (up to 27" long), or for larger sizes, time expired or damaged full-size helicopter rotor blades (maybe tail rotor blades?) could be worth a look. Robinson R22 blades have to be replaced at 2200 hours, so you could contact owners or service centres to find out what happens to the old ones.

Search a well known internet auction site for 'carbon rotor blades' to find the model helicopter blades. Search in 'Aircraft Parts & Accessories' for something like this (not sure what the construction is though...): Ex RAF Lynx Helicopter Tail Rotor Blade Part No WG1339-7001 [PAL] | eBay (http://www.ebay.co.uk/itm/Ex-RAF-Lynx-Helicopter-Tail-Rotor-Blade-Part-No-WG1339-7001-PAL-/141140534740?pt=UK_CPV_Aviation_SM&hash=item20dca1a5d4)

If you were building up your own foils, then Woolmer Forest Composites (http://www.woolmer.co.uk) sell various pultruded carbon sections that could be used for spars. Or for an Oz equivalent: Carbon fiber Australia (http://www.carbonfiber.com.au/index.htm)


Or you could try these people: www.cstcomposites.com/products-and-services/tubes-rods-and-components/foil-and-elliptical-tubes/ (http://www.pprune.org/www.cstcomposites.com/products-and-services/tubes-rods-and-components/foil-and-elliptical-tubes/)

[Andy_P]

Thanks for those links. Most mobs like CST and C-Tech dont sell naca sections, just elliptical. I want a proper foil shape because its going to be near water, and in rough seas round sections create to much drag in the waves.

The R22 blades sound promising. There is a heli service place at the airport I fly from, so I will go ask the question next time I am there.

[phiggsbroadband]

Hi Andy, you could contact your nearest aero-modelling club, they might have designers that can mould GRP sections. The usual scheme involves cutting blue foam into the right section with a hot wire and template, then layering the GRP over the top, with a final pigmented gel-coat.
If you use carbon fibre, you can choose how many strands are in each direction, for the strength that you require.