My regular flight instructor had to deal with some car trouble last thursday, so I flew with this other guy.  We talked a bit about aerodynamics before we went up, and he mentioned something counterintuitive / interesting / tragic about dive-bombers in WWII.

We lost a whole lot of them, which in itself isn’t shocking, but what’s odd is why we lost so many.

The problem wasn’t that:

• They exceeded the do-not-exceed speed of the airframe, ripped it apart, and crashed.
• They were usually headed directly into a hail of high-caliber and/or incendiary ammunition, which riddled / ignited the aircraft and subsequently caused structural failure / more crashing.
• They misjudged their altitude and biffed the target / ocean / ground.

Despite the fact that a dive is the single highest-speed maneuver one can perform in an airplane, the problem was often that they aerodynamically stalled the aircraft while trying to exit the dive.

One of the “flying 101″ definitions that gets drilled into your head is that a stall will occur at any speed, and any gross weight if the angle of attack (the acute angle formed by the wing chord line and the relative wind) exceeds some critical upper limit (ie - the critical angle of attack).

That law makes all kinds of intuitive sense when you consider a plane flying horizontally, then pitching up to exceed the critical angle of attack.  The relative wind in that case is parallel to the earth’s surface, which feels natural.  But it somehow becomes much less intuitive when you consider a plane flying straight down, then pitching relatively-up toward the horizontal plane.  The relative wind in that case is headed straight up, “out of the Earth”-ward.  Irrelevant rationalizations enter your mind, like “he’s still going so fast, and there’s gotta be more relative wind coming from the right, yeah?”  Negative.  The law doesn’t care what direction you’re traveling in, or where the Earth is.  You exceed the critical angle of attack, you stall.

So there you are, some poor bastard in a 1940s-era warbird, hurtling toward Earth and well-armed enemy at somewhere near the speed of God, and you survive long enough to drop your bomb.  “Whew,” you think, “time to GTFO” and jerk back the stick to stop pointing at the ship, the thousands of rounds being fired at you, and the Earth.  Suddenly the controls get all mushy, and just like that you’re no longer hurtling forward, hands first toward the ground at insane speed, but tumbling down, ass first at nearly the same speed.  You can’t see it, but you know it’s coming.

Shitty.

The positive take-away, though, is that a combination of independent study and supervised training under controlled circumstances can allow a man to win battle after battle against unintuitive and potentially dangerous branches of scientific truth.

Apple publishes a specially formatted file which powers another website’s human-friendly representation of the data.

While looking at that page, I caught myself projecting sweeping personality demographics (some virtuous, some slightly contemptible) in the data, despite its hugely-lossy compression.  To join me in this exercise, you first need to know that the 3g iPhone is available in exactly three flavors: 8GB Black, 16GB Black, and 16GB White.  I interpreted the “out of stock-ness” as follows:

8GB black:
“I’m not paying extra for additional utility or additional bling.”

16GB black:
“I have the resources to get the one with the best available feature set, but I’m not particularly interested in telegraphing the fact that I paid extra for the 16GB version.”

16GB white:
“I have the resources to get the top of the line model, and I want you to know it.”

Locales (as of this writing) where only 8GB black is sold out:

• Birmingham, Alabama
• Tampa, Florida
• Indianapolis, Indiana
• Hingham, Mass.
• Troy and Ann Arbor, Michigan
• Huntington Station, New York
• Columbus, Ohio
• Austin, Texas
• McLean, Virginia

My theory about Austin TX and McLean VA is that lots of workers independently purchased iPhones to replace their BlackBerrys, with an eye toward expensing the cost.  Or, a huge volume of corporate iPhones purchased through AT&T Premier accounts has cut disproportionately into 8GB black iPhone stock in those areas.

But let’s get to the “drinking the Hatorade” part: locales where only 16GB white is sold out:

• Tucson, Arizona
• Palo Alto / Stanford, California
• White Plains, New York
• Victor, New York (Eastivew, “the mall where the white people go” in this suburb of my hometown Rochester, the same mall where to my eternal shame and in a move totally out of character I once applied for a job working at Aeropostale…and appropriately did not hear back)
• Houston, Texas

If you find this interesting at all, have a look at the linked page for the “I might not spend extra, but if I do I want you to know” locales, the “if I’m spending extra, it’s just for more space” locales, and the “by god, give me any iPhone you still have available” locales.