by Matthew Cobb
Jerry wants me to post on that story from Nature about Ediacaran fossils having been the fruiting bodies of terrestrial fungi, but that will have to wait until I’ve finished marking a load of essays. In the meantime, have fun with this:
Space Odyssey: The Reboot
(AKA: Ping pong on the Vomit Comet)
I would love to try this at home, but, sadly, I lack the laboratory facilities. Can I borrow yours, please?
Needs fewer teachers and more ping-pong balls.
If my mum was still alive she’d say something like, “Now who’s going to have to clear all those up when they’re finished?”
You can tell that I’m very definitely my mother’s son by the fact that my first thought was “Cool!” and my second was “Now who’s going to have to clear all those up when they’re finished?”
Sadly I find myself strangely 727-less so I’ll have to defer trying this until I can rectify the situation.
Mike.
Bugger the ping pong balls, tell us about the Ediacaran fossils!
HAL: What is going to happen, Dave?
Dave: Something wonderful.
HAL: I’m afraid.
Dave: Don’t be! We’ll be together.
HAL: Where will we be?
Dave: Where I am now.
In the 80’s, I had the noise for an erroneous key stroke on my Mac (you, know, the old ‘puter usually beeps at you when it can’t do what you are keying) say: “I’m sorry Dave, I’m afraid I can’t do that” recorded from the movie. It was hilarious (even though it delayed you just a bit).
Can Macs still do that (assign sampled sounds to various sound-inducing events in the computer)?
But how does this prove that “Evolution is True”? (I invite creative responses.)
Specifically: Humans evolved to handle (free fall) motions better than passive ping pong balls.
Generally: Evolution stands as a process analogous to how gravity is a process.
Do I rate an E or E- on the essays? (F is for “F_ing trying”, right?)
Kind of funny when the gravity returns and they all crash to the floor. You can hear some guy in the background shouting “give us some warning!”
..and in the second angle the woman hits the floor and says ‘ow’.
Finally a post about mass quantities of ping pong balls!
That looked like a pretty bad parabola. I think they’re usually longer and more consistent.
Observation 1: the levitavity (a newly Coyned term) of teachers are akin to ping pong balls.
Observation 2: I didn’t know 727s could do free fall parabolas.
Quite a few different aircraft have been used to perform this maneuver over the years. Pull up to initiate a climb and then power back and push the nose down. The microgravity begins while the plane is still moving up and continues until the following dive has reached maximum safe speed and the pull up and climb starts all over.
See Vomit Comet at Wiki.
You too can experience this if you really do want to, just contact Zero Gravity Corp. Rather than the 50 or so repeated ups and downs, they will only subject you to about 15 cycles, making it more likely you will keep your lunch.
It’ll set you back about $5000 and is made available in various US cities by reservation.
All commercial jet liners are designed to the same loading conditions since the 1950s (except for some fatigue spectra and a few specialized cases that don’t affect the issue here.)
They can handle (fully loaded or empty — the inertial loading on the fuel helps react the air loading in a positive G maneuver) 3.75-G up and 1.5-G down. The top of the push-over is intended to track at 0-G (obviously) but it could have been at -1.5-G
These are Ultimate loads (normally this coincides with the predicted failure point for the least-strong part of the plane). The Limit Loads (highest expected in service) are +2.5G and -1.0G.
I’ve flown on flight tests (I used to design wings for Boeing) at around -0.1-G and +2.0-G. They are exciting.
In case you’ve ever wondered about whether the airplane wing can handle the turbulence in flight: Commercial airliners are essentially always maneuver critical, not gust critical. To fail an airplane wing, it will be deflected at the wing tips something in the range of 10-feet to 25-feet (3m – 8m), dependeding on the size and its design. So your gust that is moving the wing 0.5-1 foot, is nothing. It does contribute to the fatigue spectrum.
Sometime back there was a Chinese 747 that had an interesting incident. They ended up pulling over 4-gs (luckily in the + direction and, also luckily, the plane was lightly loaded). The high speeds caused some of the tail surfaces to flutter to failure. The high-g forces permanently deformed the wing (when you go above Limit Load, some permanent deformation is expected). And according to my firends that were in the service group, it improved the fuel economy of the plane(!).
My cats would love that!