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Musical Wings Reduce Aircraft Stall Risk

notwrong writes "The Sydney Morning Herald is reporting that a Qantas engineer has found a way to help small aircraft avoid stalling at low speeds: pumping sound through the wings. He found that music also works, having tested Spiderbait and Radiohead (nice choices; Spiderbait apparently works better)."

18 of 235 comments (clear)

  1. Other bands to test... by Anonymous Coward · · Score: 5, Funny

    I would think that playing the B-52's, U2, Eagles, Foo Fighters, a Flock of Seagulls, or Jefferson Airplane would be more appropriate, then again, who am I to say...

    1. Re:Other bands to test... by FidelCatsro · · Score: 4, Funny

      Lets not try "System of a down " though

      --
      The only things certain in war are Propaganda and Death. You can never be sure which is which though
    2. Re:Other bands to test... by Hogwash+McFly · · Score: 4, Funny

      Lynyrd Skynyrd?

      Define irony: a bunch of idiots dancing around on a plane kept in the air by a song made famous by a band that died in a plane crash.

      --
      Mother, do you think they'll like this sig?
  2. Just hope.... by metricmusic · · Score: 5, Funny

    they don't play 'Crash and Burn' by Savage Garden.

    --
    http://www.livejournal.com/users/metricmusic
  3. Mr. Qantas aerospace engineer.. by lightyear4 · · Score: 5, Funny

    ... you are the wind beneath my wings.

  4. new business model for the RIAA by Anonymous Coward · · Score: 5, Funny

    From now on, every small aircarft owner must pay royalties to the RIAA. Otherwise RIAAAF rules of engagement will not apply.

  5. Re:As a pilot by madaxe42 · · Score: 5, Insightful

    As a pilot, I think it's just fine. If you don't like it, don't use it. Oh by the way did you know that Boeing use a Linux supercomputer to help design their aircraft? And all the new in-flight entertainment systems are based around linux? And, oh, guess what, some new nav computers use.... you got it, Linux.

    Suggest you quit your job and start living in a cave, to avoid linux. Oh, maybe you already do, troll.

  6. I dunno... by darkov · · Score: 4, Funny

    filling wings with rock doesn't seem like such a good idea.

  7. Next time I go flying by LupeSpywalper · · Score: 5, Funny

    I'll bring my air guitar.

  8. Hmm... by YeEntrancemperium · · Score: 5, Funny

    Will the plane explode if you blast some Necrophagist, Psycroptic, or Nile?

  9. Isn't this just an example of dither? by kjoonlee · · Score: 4, Interesting

    If added noise makes the flight smoother, isn't this dither?

    http://en.wikipedia.org/wiki/Dither

  10. Re:As a pilot by drgonzo59 · · Score: 5, Informative
    I think Boeing's flight control computer is based of Integrity-178B by Green Hills that uses a separation kernel. In fact there is LynxSecure, AESecure, VxWorks and LynxOS-178 but Integrity-178B is by far the one with the smallest separation kernel thus the more secure one. Because it can be mathematically proved that it is correct (does what it is supposed to do and nothing more or else),so anything with 500,000 lines (think Linux kernel) is no good for that, need something that is no more than a couple of thousand lines and it still can take up to 2 years to complete the verification process.

    So what do you do if ya want complex and sofisticated system calls that the Integrity-178B doesn't provide? Well, use another real-time os on top of Integrity-178B or make it part of Integrity-178B but run it in user mode. So all the drivers are really in user mode in such a system. This all is needed so that no single program if corrupted can hang the system. (Trust me you don't want an airliner's computer to freeze with a BSoD or with a Oops!-Kernel Panic while in mid-air).

    Another side note, FAA actually has a concrete limit on the failure due to software. So something like no more than once out of tens of millions of flight hours a plane full of people is allowed to completely crash and burn because of a software problem and have everyone on board die a horrible and painfull death and that would be perfectly "ok" with FAA. So the requirements to certify a system (OS) to fly a plane are very stringent. Linux doesn't even come close. It might be good enough to play music though...

  11. Just like birds? by psoriac · · Score: 5, Interesting

    I may be talking out of my ass here, but don't bird wings do the same thing when their feathers ruffle as air passes over them? Wouldn't this ruffling be the same as the vibration described in the article?

    --
    I browse Slashdot at +3, Funny
  12. Musical wings by jcater · · Score: 5, Insightful

    This is a well known phenomenon. The question is how much energy is being used to get this reduction in drag?

    Where does this energy come from? Either APUs, or more powerful main engines... which are heavier... which means bigger wings...

    1. Re:Musical wings by thesupraman · · Score: 4, Insightful

      >This is a well known phenomenon. The question is how much energy is being used to get this reduction in drag?
      >Where does this energy come from? Either APUs, or more powerful main engines... which are heavier... which means bigger wings...

      Of course, if the effect they were discussing was a reduction in drag you may well have a point, since reducing the low speed stall of the wing was the actual effect I guess you missed the mark a little.

      But of course, this is a well know effect. The sound produces surface turbulence in the zone where the laminar flow breaks down, and helps to keep the flow attached to a slightly higher angle of attack.
      Generally 'tripwires', surface steps, and small turbulator fins are used for this effect, however they operate at fixed positions. This system is a little more general, although comes at an energy (and indeed drag) cost.

      An interesting approach would be to detect the development of stall and hit the vibration generators then, which would work great except it is very hard to re-attach flow once it breaks down, and very hard to detect stall before the flow detaches.

      All in all, someone with a media connection has decided to ride a bit of common knowledge, good on them.

  13. Iron Butterfly by warthog442 · · Score: 4, Funny

    We tried this years ago, but the plane would only stay up for 17 minutes and 2 seconds, wierd...

  14. Re:As a pilot by drgonzo59 · · Score: 4, Informative
    It is not quite the halting problem.

    Imagine that you have a 3 line program that computes the absolute value of some input x say {if(x>=0) abs=x; else abs=-x; return abs;}. Ok do you think you'll be able to write another program that will verify that this program works correctly?

    You would look at it and perhaps see that it has one branch. We give it inputs such that both paths in the branch are taken and then you look at the output and see if it is what you want it to be, and _also_ you look at all the rest of the memory and make sure that it didn't change. Maybe give it some extreme values, like the maximums and minimums and then also look at output and the _whole_ memory.

    Then can you do the same for a 'for' loop that computes a dot product. You just give the program the known input then at every iteration look for some loop invariants and also check the rest of the memory that shouldn't be affected that it is indeed not affected and then check the output.

    Also this means that the code itself has to be written in a certain way in order for its correctness to be checked easily. That means that a lot of nested 'if's are not a good idea, so they try to reduce the branching as much as possible and modularize the program. It is the burden of the software developers to submit their code for certification and pass before it is accepted by FAA or DoD.

    This actually can be reduced to the SAT problem, which runs in exponential time (but there are ways to take shortcuts in some of the cases).

    I would think that some actual application code that runs on it would define what the system does.

    First though before you even let any application code run you have to make sure that no single appliation will ever take control of the memory and cpu for more than it's allowed share. That is what the separation kernel does. You run this small provem and scrutinized piece of code (note: you also need specialized hardware to make sure it will work) that makes absolutely sure (up to a margin of error) that no application will take more than its share of resourses. So if one application crashes it will not crash the system, instead the rest of the machine will continue to work. So that is why sometimes they will run two RTOSes on top of each other with the first being Integrity-178B that will make sure the other OSes on top are partitioned and separated and allocated only a given share of resourses.

  15. Vortex Generators by Nick+Driver · · Score: 4, Insightful

    A popular aftermarket wing mod is vortex generators... little pieces of metal or plastic carefully positioned at stretegic intervals along the top of the wing skin, usually just a little ways aft of the leading edge. This induces vortices in the airflow to help keep the boundary layer across the top of the wing from separating off from the surface, and thus lowers the stalling speed by some small amount.

    I am a pilot who flies my own small plane and prefer to simply keep my airspeed up to avoid stalling the wings, and keep the music in my headsets. An iAudio X5 mp3 player fed thru a set of Lightspeed Thirty 3G ANR headsets while you're flying is a great experience. ...and yes one of the very first times I took off with music playing just had to be with Steppenwolf's Magic Carpet Ride, as I was haulin' ass down the runway thru rotation and climb-out (ST:First Contact reference).