The trend is to not patent an actual wing design and to instead hold it as a trade secret. I don't think business has any right to have a place in research. I've had beef with NASA and Boeing for 8+ years IMO, those making the decisions are only interested in ROI. For that, if NASA wants to give up on aeronautics, IMO, they should drop the the first 'A'. But if Boeing does more research privately, the burden of cost goes to the smaller companies and soon NASA may cancel projects due to no one using/affording the ideas. Pretty soon, those large companies become like customers and to satisfy them, NASA would have to cater to them. in which there a so few companies big enough to really use those ideas, in terms of investing in those ideas. Boeing does their own airfoil research and they have patented some of the airfoils they have developed. Their aim has been to demonstrate a level of technology that other people can either use or improve upon. I'd like it if someone could verify that story, it's been a few years. IIRC, the air didn't circulate properly underneth a critical portion of the wing. This was primarily due to not having the Reynold's number high enough. I agree! When I was in wind tunnel lab, our professor told us a story that Boeing was embarrased to find out that their 777 in flight had a 0.01 Mach increase in cruise compared to CFD solutions. Not true! While there was a lot of CFD work done on the 777, it also was heavily wind tunnel tested Risk reduction is everything in the development of an airliner and the wind tunnel serves as a risk reduction tool. This testing was done in the Boeing Transonic Wind Tunnel (BTWT), the NASA Ames 11' Unitary tunnel, the NASA Langley National Transonic Facility (NTF) and the RAE Pressure Tunnel. Not true! While there was a lot of CFD work done on the 777, it also was heavily wind tunnel tested. And that's if your computer is big enough and fast enough to create the massive grids and do all the calculations. These days, CFD predictions are getting better than wind tunnel tests for cruise, at least. The B777 never went near a wind tunnel, AFAIK. The wing of the 707 uses NACA 6-series airfoils, with modified camber lines. The NACA 64A010 is very common in such applications. Now, any large commercial aircraft wing is swept, tapered and twisted so a particular section across the whole span is just not suitable, or efficient.Īctually, the NACA 6-series airfoils were found to work very well on swept wings and thus were used on many swept wing aircraft. NACA airfoil sections were great when aircraft had unswept constant chord wings and it made it easier to predict behaviour. I guess I have to wait to Senior year before my courses start teaching me the modern stuff.or is it true what they say.that the stuff you learn in college is outdated anyway? Oh well, the degree and the insight gained will get me in.I'll learn more as I go along.īut what to do with my kick ass MATLAB script, lol! (Let's just hope in that case it really doesn't turn out to just be maynaise left in the sun!) I guess now it'd be a stretch to ask if the zero-lift angle of attack and lift curve slopes for mordern wings are available anywhere as I suppose companies will be a bit more secretive a la "secret sauce". I suppose the term airfoil will now be more educational than design oriented since the concept at least helps in aeronautical instruction. So is it fair to say that the NACA airfoils will now collect dust? This is pretty interesting to me, as my sophomore Aero Design class spent a portion of time on 2-D aerodynamics involving airfoils. The old days of going into the wind tunnel with a half-dozen or more candidate wing designs are gone. Transport aircraft wings are designed using CFD and wind tunnel tests are later performed to confirm the predictions.
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