Monday, February 15, 2010

A380 wing skins

The secret of the A380 wings is finally revealed. Check out this article. Apparently, each skin panel is prestressed in a custom jig and autoclaved. When it comes out, sproing!, it's the right shape. Nifty, eh?

Sunday, February 14, 2010

My first A380 flight

I recently went on a business trip to Sydney. On the outbound, I chose to go directly from KSFO to YSSY to save time. On the return, I went through KLAX specifically because the YSSY-KLAX leg was on an A380. This is my report of the journey on Qantas flight 11.

At YSSY, I couldn't see too much of the aircraft because of the sheer volume of the three jetways leading up to it.


No matters, though. Welcome aboard!


Notice the nice bright new shiny anodized door latch hardware. It's the details that matter, you see. Once in, the economy class cabin is nice if not ostentatious:








Notice that the plastic parts of the seats are carbon fiber. This is not just a "look": By moving back the edge of the upholstery, I could tell that the reverse side is also carbon, and the edges look black even though the resin is transparent. Most likely: they are real carbon. Nifty!

The seats articulate such that, as the back is reclined, the seat pan moves foward. I would have loved to un-Velcro all the padding to show you how this clever design feature is made possible, but that might have gotten me into trouble, so I chose to demur. Instead, I'll point out that, apparently, the aircraft seatbelt latches of the future are automotive-style, not airplane-style:


Behold the mighty wing that is to hold all this stuff up in the air:



Now on to the star of our performance: The tail-mounted camera. This one thing is so useful, so awesome, that it makes me want to grab a step drill and Jilson snips and add this to every commercial heavy on the planet. Here we are at the gate:


Who wants an entertainment system that shows movies on demand when you have that, eh? Here we are ready for our takeoff roll:


And on climbout, with nifty vortices and Sydney harbor in the background:


Speaking of which, let's look at that wing in flight one more time:


Notice anything? Yes, compared to the ground photo, you can see the wing outboard of the #4 engine pylon. Curved downwards on the ground, the wing straightens in flight.

Ok, here's a quick weekend project. Design a reliable, strong and lightweight mounting, articulation and actuation system for the wing control surfaces. This must take into account the flexure of the wing, and specifically, should maintain proper slot geometry for flaps and slats all along their length at all aerodynamically significant conditions. Remember that, if your mounting is off the neutral axis of the wing, the spanwise distance between your mounting points will change as the wing flexes.

(Yes, I know this is a previously solved problem: all large aircraft must be designed with wing flexure into account. But, in this case, it's particularly dramatic.)

Another weekend project: Design a wing that is curved downwards when unstressed. Now manufacture it. Notice that, strictly speaking, your unstressed top and bottom skins are actually double-curved.

And now on to the only way to go flying, as ordered by Doctor Awesome:


This is me programming, while keeping tabs on our status. :) Unfortunately, there is one source of silliness: the "warning" on the display. This comes up, and makes the rest of the screen "grayed out", whenever there is a PA announcement. How annoying. Hrmph. Incidentally, the power connector is on the back of the armrest of the seat in front of you (it took me a while to find it):


There are RJ-45 and USB sockets on the end of your own armrest, but on my flight, these did not provide any useful connectivity (though perhaps the USB was powered).


One of the "problems" with this ship is that it is noticeably quieter than the average commercial heavy. Why is that a problem? Because the all-night chit-chat of the flight crew in the nearby kitchen was audible enough to keep me up! D'owww! :) It did not help that I was consuming uppers and downers together:


Obligatory potty shot: The faucet is temperature adjustable and activated by a proximity sensor, like all decent bathrooms worldwide. Why it took so long for aircraft to adopt this "new" idea is totally beyond me.


Finally, we arrived, a little bleary-eyed but none the worse for wear. Here is an awesome, if blurry, shot of us approaching the California coastline with spoilers deployed:


Flying what looked like a downwind for KLAX 24R:


Turning final, likely over PALAC, with downtown LA in the distance:


And braking on the ground:


Finally, it's time to say goodbye to my ride: