Looking at my 1150 next to a 999, wondered if anyone had chopped an inch off the tips to give it more if an art planshape. Thoughts are to help with tips coming out....surely that narrow tapered last inch isn't doing much more than inviting ventilation? ( I still love my 1150 how it is, I was just wondering)

If you're looking at chopping the wing you may want to think about changing up either your mast if you can go longer or changing up the wing itself. If you really love the wing and breaching is the only problem, a longer mast should help out.

DC

That sounds like a really bad idea.... the foil section is completely different, you won't get much of a speed advantage on a pumping wing.

Also if you shop chop you'll run into the foam and have to seal it with filler.

You will loose glide, you will not gain speed, you will need to fill when you hit foam.

If you decide to follow this. Get in contact with your local foil shop and order a new 1150, you'll be needing it after you ruin this one.

Select to expand quote

King Crash said..
You will loose glide, you will not gain speed, you will need to fill when you hit foam.

If you decide to follow this. Get in contact with your local foil shop and order a new 1150, you'll be needing it after you ruin this one.

Yeah but do you think he should do it?

As much as I love chopping things , taking off the ends of the 1150 won't do much , it's too thick on the ends . The 1150 is the big cruisy girl that's her job . Tight turns and tip breaching is not what it is designed for . You'll get more positive results taking an inch off the ART's . I only ever used the 1150 is super light wind , de tipping it will loose the early lift and probably slow it down. Just get a 1099 ART you won't know yourself.

I got a 1099....its a weapon.....but it was what got me thinking about those tips. ARTs are a progression of the design process and the squarer tips do seem to breach better. I also think that the bulk of the low end lift (and drag) is from the middle of the wing. Anyway, I was just curious. I've made a few of my own wings and the results of modifications are always surprising (usually good, ive never "ruined" one) for me. If my 1150 was a bit more beaten up I'd maybe think about it. I only use it for dock starts, tiny wave conditions proning, and learning to paddle up my sup, so the tip breaches only affect the proning, and then it is when I pop over the back of a wave, so its no big deal, prob more skill than wing adjustment needed. Thanks for looking, and if you've actually tried it I'd love to hear about it....

Breaching behavior is about light loading at and near the wing tip, which is managed with twist, flattening camber, and possibly changes to foil section near the tips. Once the spanwise lift distribution is dropped down near the tips, spending spending surface area on taper of some shape could just be adding drag if not perfectly shaped, so might as well skip that and have squared off tips.

In other words, the squared off tips are an optional side effect of designing a foil that breaches well, not the cause. Watch the latest Blue Planet podcast with Adrian Roper for some great designer insight. The 1150 is not designed like the ARTs and squaring squaring tips off won't make it behave more like an ART.

Fair call, its not an ART, but it works on the Armstrong 1250. I copied one of these, but gave it a foil section off an HPS 880. It was a shocker at breaching tips, and had similar tapered tips. This thread us a spin off from thinking about why chopping works on a 1250, albeit at the expense of some lift.....

Did the 1250 chop make actual breaching better or just reduce breaching occurences due to reduced span? My understanding with Armie stuff was that it generally doesn't breach well so chopping was a way to avoid or limit occurrences of getting the tips out. No firsthand Armstrong experience though.

Like I said, outline and foil section alone don't determine spanwise lift distribution, twist and camber are big elements in getting the tips to play nice when they come out. Very hard to measure these accurately enough to copy well.