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I have no idea how it ended up on the front page of HN, but this is an amazing book. Highly recommended for any pilot, especially those flying small airplanes.

I have no idea how it ended up on the front page of HN, but this is an amazing book. Highly recommended for any pilot, especially those flying small airplanes. Don't let the date scare you, it holds up incredibly well. Wolfgang figured out how to describe things that good pilots do unconsciously in a way I've never seen matched. I'd like to share one passage that because of a small aside in the middle of a sentence has stuck with me for years. Of course it is conceivable that a perfectly maintained airplane, perfectly trimmed and flying in smooth air, might continue to fly straight ahead indefinitely simply because it would never be disturbed, would never get that first slight deflection from straight flight which starts the spiraling. But it is also conceivable that a pencil, stood on its point, might be so perfectly balanced and so completely shielded from all disturbances that it would stand on its point indefinitely. Both things are philosophically possible; both are so highly improbable as to be practically impossible. And anyway, the stability of a thing, just like that of a man, does not consist in its being shielded from all disturbances and thus preserving a precarious balance; it consists in the ability to recover from disturbances that inevitably will occur, and to regain lost balance.

userbinator 8y ago
Don't let the date scare you, it holds up incredibly well. Indeed, the laws of physics have not changed. It seems like a lot of people are turned off by old books, when I've found that my experience has often been the exact opposite --- for subjects like maths and electricity, the very old books had a way of explaining things that makes them quite easy to understand and perhaps even better than the new ones which simply glance over a subject and almost assume knowledge.
- slazaro 8y ago
  > Indeed, the laws of physics have not changed. That's not the reason people might be hesitant to read a book from the 1940s. Technology changes a lot, and maybe things changed in airplanes to make it obsolete, maybe not. That's why that comment was necessary.
  - mseebach 8y ago
    Also: our understanding of physics has evolved: https://en.wikipedia.org/wiki/Lift_(force)#Alternative_explanations,_misconceptions,_and_controversies https://en.wikipedia.org/wiki/Lift_(force)#Alternative_expla...
    - oldcynic 8y ago
      That explanation hasn't exactly died out these days even if you won't find it in official sources.
hyperpallium 8y ago
An example from hang gliding: the wings form a shallow "V", with you at the centre. If it tilts left, there's more lift area downwards on the left (and less on the right), so it tends to tilt back, righting itself. I'm not sure what prevents oscillation; nor how pitch is stablized (pointing downwards vs pointing up), but I've found hang gliders very stable.
- unoti 8y ago
  Pitch is stabilized by the tail. When the nose points down, air hits the top of the tail and pushes the tail down, bringing the nose up. And when the nose is pointing up, air hitting the bottom of the tail pushes the tail up. The V shape thing you mentioned for hang gliders is also true for most light planes. It’s a self stabilizing thing. I think what prevents th oscillation is that as it comes to level, the amount of upward force from the other wing equalizes.
  - mannykannot 8y ago
    Yet canards can be made stable in pitch as well. In either case, the 'trick' is that the forward plane, whichever one it is, should be rigged at a higher angle of incidence than the rear plane.
- snt 8y ago
  The "projected area" theory is a common misconception of how dihedral works (that I also subscribed to for many years). All things being equal, the port and starboard wings create the the same amount of roll torque, no matter which one is 'facing' the ground better (of course, dihedral does still work, because all things are not equal). https://aviation.stackexchange.com/questions/26759/how-does-the-dihedral-angle-work https://aviation.stackexchange.com/questions/26759/how-does-...
  - dTal 8y ago
    Check out page 126 of Stick And Rudder for an intuitive illustration of why dihedral works.
mannykannot 8y ago
The airplanes people first learn to fly have hardly changed since then, with, I would say, tricycle undercarriage being the biggest change, followed by more docile stall/spin characteristics, in particular in being less likely to drop a wing in a stall. After that: engine reliability. I occasionally read accounts of flying the first generation of airplanes (or replicas), and it does seem to have been rather different then, not so much in first principles as in the craft of making it work. If I am remembering this correctly, some pilots of piston-engined transport aircraft had difficulty transitioning to jet airliners, a problem addressed by an influential and well-regarded book (Davies, "Handling the Big Jets", 1967?)[1] which, among other things, recommended putting aside the "throttle for height, stick for speed" principle. [1] See, for example, https://www.flightglobal.com/FlightPDFArchive/1967/1967%20-%200708.PDF https://www.flightglobal.com/FlightPDFArchive/1967/1967%20-%...

userbinator 8y ago

Don't let the date scare you, it holds up incredibly well. Indeed, the laws of physics have not changed. It seems like a lot of people are turned off by old books, when I've found that my experience has often been the exact opposite --- for subjects like maths and electricity, the very old books had a way of explaining things that makes them quite easy to understand and perhaps even better than the new ones which simply glance over a subject and almost assume knowledge.

slazaro 8y ago
> Indeed, the laws of physics have not changed. That's not the reason people might be hesitant to read a book from the 1940s. Technology changes a lot, and maybe things changed in airplanes to make it obsolete, maybe not. That's why that comment was necessary.
- mseebach 8y ago
  Also: our understanding of physics has evolved: https://en.wikipedia.org/wiki/Lift_(force)#Alternative_explanations,_misconceptions,_and_controversies https://en.wikipedia.org/wiki/Lift_(force)#Alternative_expla...
  - oldcynic 8y ago
    That explanation hasn't exactly died out these days even if you won't find it in official sources.

hyperpallium 8y ago

An example from hang gliding: the wings form a shallow "V", with you at the centre. If it tilts left, there's more lift area downwards on the left (and less on the right), so it tends to tilt back, righting itself. I'm not sure what prevents oscillation; nor how pitch is stablized (pointing downwards vs pointing up), but I've found hang gliders very stable.

unoti 8y ago
Pitch is stabilized by the tail. When the nose points down, air hits the top of the tail and pushes the tail down, bringing the nose up. And when the nose is pointing up, air hitting the bottom of the tail pushes the tail up. The V shape thing you mentioned for hang gliders is also true for most light planes. It’s a self stabilizing thing. I think what prevents th oscillation is that as it comes to level, the amount of upward force from the other wing equalizes.
- mannykannot 8y ago
  Yet canards can be made stable in pitch as well. In either case, the 'trick' is that the forward plane, whichever one it is, should be rigged at a higher angle of incidence than the rear plane.
snt 8y ago
The "projected area" theory is a common misconception of how dihedral works (that I also subscribed to for many years). All things being equal, the port and starboard wings create the the same amount of roll torque, no matter which one is 'facing' the ground better (of course, dihedral does still work, because all things are not equal). https://aviation.stackexchange.com/questions/26759/how-does-the-dihedral-angle-work https://aviation.stackexchange.com/questions/26759/how-does-...
- dTal 8y ago
  Check out page 126 of Stick And Rudder for an intuitive illustration of why dihedral works.

mannykannot 8y ago

The airplanes people first learn to fly have hardly changed since then, with, I would say, tricycle undercarriage being the biggest change, followed by more docile stall/spin characteristics, in particular in being less likely to drop a wing in a stall. After that: engine reliability. I occasionally read accounts of flying the first generation of airplanes (or replicas), and it does seem to have been rather different then, not so much in first principles as in the craft of making it work. If I am remembering this correctly, some pilots of piston-engined transport aircraft had difficulty transitioning to jet airliners, a problem addressed by an influential and well-regarded book (Davies, "Handling the Big Jets", 1967?)[1] which, among other things, recommended putting aside the "throttle for height, stick for speed" principle. [1] See, for example, https://www.flightglobal.com/FlightPDFArchive/1967/1967%20-%200708.PDF https://www.flightglobal.com/FlightPDFArchive/1967/1967%20-%...