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what a world we live in, The Authorities have decided it's ok to use a mobile phone in flight, and yet I'm still not allowed to bring a cup of yogurt airside.
Finger Prince fucked around with this message at 05:41 on Nov 2, 2013 |
# ? Nov 2, 2013 05:37 |
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# ? May 25, 2024 03:21 |
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I have left my phone on numerous times while flying by accident, and each time I've noticed above 25000' or so I have had no signal. When I used to fly King Airs, we had CDMA company phones and those things did work up to around 23000' but we were flying far slower. Not sure if IPhones are magic but I don't see much of a change unless cell technology changes too.
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# ? Nov 2, 2013 07:14 |
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Well, no cell phone use helps cut down on passengers who talk on theirs constantly. But in other annoyances, as much as I love the increase in IFE, the lack of arm rest controls leads to having the back of your seat tapped through the flight. The games are the worst... Here's how a washer destroyed a 737: http://lessonslearned.faa.gov/ChinaAirlines120/ChinaAirlines120_Downstop_pop_up.htm http://lessonslearned.faa.gov/ChinaAirlines120/ChinaAirlines120_Evacuation_pop_up.htm China Airlines Downstop Failure Animation Audio Transcript posted:On August 20, 2007, a Boeing 737-800 operated by China Airlines departed from Taiwan and had an uneventful flight to Naha Airport, Okinawa, Japan. The 737-800 employs a high-lift system that includes leading-edge slats which enhance takeoff and landing performance.
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# ? Nov 2, 2013 07:21 |
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Lucky that happened on the ground. I'm glad nobody was hurt. It's also a bit ironic that shutting off the engine actually allowed the fire to start.
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# ? Nov 2, 2013 09:29 |
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CharlesM posted:Lucky that happened on the ground. I'm glad nobody was hurt. It's also a bit ironic that shutting off the engine actually allowed the fire to start. I must say that dude trying to stop the fire hydrant made me laugh... Yeah that'll stop a few thousand litres of petrol from burning. Plus he's just waving it randomly, not even aiming at flames. He was lucky he wasn't standing there a few more seconds when it exploded...
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# ? Nov 2, 2013 09:57 |
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I was just reading the training manual about fuel leaks and how they're only noticeable in flight by doing flight plan checks vs. actual readings. I wonder if it would have been better in flight, given that whatever fuel lost wouldn't have had detriment to the total flight. Airflow and engine exhaust would have just taken the leaked fuel away. If a short enough flight and enough leaked out to be noticed but no longer keep seeping out once on the ground to then get on the brakes/engine maybe it wouldn't have caught fire. But that's a lot of perfect variables that never quite line up.
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# ? Nov 2, 2013 10:07 |
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Im kinda surprised that it took over 3 minutes for the fire trucks to arrive- you'd expect that as soon as someone says "Fuel leak" they'd be notified and be on scene as the aircraft was pulled up- If they had been there earlier there wouldnt have been anywhere near the level of flamage.
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# ? Nov 2, 2013 10:08 |
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SyHopeful posted:I'd love for either of you to do a semi-layman's writeup of what's so innovative about the 787's bleedless architecture. I think most of us know that it's A Thing and that it helps to increase the fuel efficiency over a bleed air system, but what about it is well-engineered/thought out? Basically, traditional turbine aircraft design (and by traditional I mean drat near every design for nearly 60 years is based on this) involves pneumatically-driven starter motors geared to the engine driveshaft. Bleed air, which is air siphoned from a turbine engine after it's been compressed, is used to drive the starters which in turn spins the driveshaft of the turbofan, drawing in air and causing enough compression to start. This bleed-air can come from the other engine, a start cart (on older designs), and most commonly from the APU. Now, the bleed air drawn from the APU has to get to the engine starters, which on larger aircraft is a not-insignificant distance, so many designs use a compressor driven by the APU to give it that extra push to have enough pressure to crank the starters after traveling the hundred or so feet of ducting to the engines. This obviously adds quite a bit of weight and complexity to the engine start system. Also, since the whole thing basically boils down to having enough pressurized air to turn a motor fast enough to spool an engine, there is a lot of points of possible failure in the form of air leaks or stuck valves, etc., adding a lot of maintenance requirements. The 787 gets around this by using engine-driven electrical generators as the starters, eliminating the need for any external bleed air, and therefore all of the associated ducting, valves, and compressors. The generator, which normally is turned by the engine, uses power from another source to instead spool the engine driveshaft just like a pneumatic starter would. The generator gets its power from another engine, ground power, or the APU. Sound familiar? And where does the APU get power from to start? The giant lithium batteries that like to catch on fire occasionally (or ground power). No bleed air necessary at all, which saves a ton of weight and increases the efficiency of the turbines since they don't have a parasitic loss of compressed air anymore (to a point). The reason no one thought of doing this before was because generators simply were not powerful enough and would be far too large if they were. On a 767, it takes an entire turbofan engine to drive a single 120kva generator. On the 787, the APU alone has 2 225 kva generators, and each engine has 2 250 kva generators. The plane generates almost 1.5 megawatts when it flies. Yes, megawatts. That's why I said it's a natural platform for AEW or AWACS. There's so much power available that Boeing got inventive with lots of systems that, again, traditionally would be non-electric. The brakes, for example, are entirely electric, with no hydraulics at all. The only thing bleed air is used for is engine inlet anti-ice, and that's because it's relatively small impact on engine efficiency and there are some aerodynamic benefits involved. There's a few more gee-whiz details involved, especially with the power distribution system and the variable-output generators, but that pretty much covers it for the basics.
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# ? Nov 2, 2013 10:50 |
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Ferremit posted:Im kinda surprised that it took over 3 minutes for the fire trucks to arrive- you'd expect that as soon as someone says "Fuel leak" they'd be notified and be on scene as the aircraft was pulled up- If they had been there earlier there wouldnt have been anywhere near the level of flamage. There was also some controversy at the time regarding the flight crew's reluctance to order an evacuation of the passengers. Apparently it took them several minutes to determine that 1) The plane was on fire, and 2) Evacuating was a prudent measure. brains posted:The 787 gets around this by using engine-driven electrical generators as the starters, eliminating the need for any external bleed air, and therefore all of the associated ducting, valves, and compressors. The generator, which normally is turned by the engine, uses power from another source to instead spool the engine driveshaft just like a pneumatic starter would. The generator gets its power from another engine, ground power, or the APU. Sound familiar? And where does the APU get power from to start? The giant lithium batteries that like to catch on fire occasionally (or ground power). No bleed air necessary at all, which saves a ton of weight and increases the efficiency of the turbines since they don't have a parasitic loss of compressed air anymore (to a point). APUs starting from aircraft battery power are pretty typical right? Nothing about that portion of this process in the 787 is unique? Or is it an especially large APU compared to other airliners? The Ferret King fucked around with this message at 12:32 on Nov 2, 2013 |
# ? Nov 2, 2013 12:28 |
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two_beer_bishes posted:I know what you mean, I lived right by JFK (I could see the approach lights from my kitchen) in Howard Beach until April when I moved to Long Island. The biggest things out of ISP are the SWA 737s; I really miss the big stuff at JFK! That's where I live! Lenny's Clam Bar 4LYFE!
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# ? Nov 2, 2013 13:58 |
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Mistayke posted:I live within close proximity to JFK Airport over here in Queens, NY. And during the late afternoon, I saw my first A380 taking off. It couldn't have been more than a thousand feet off the ground. I live right on the approach path to Heathrow airport (Brixton, if you're curious) and the A380s are the quietest airplanes I've (n)ever heard. The 737s are fire-breathing monsters in comparison.
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# ? Nov 2, 2013 14:17 |
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brains posted:[very well said 787 ] Excellent description, much better than what I would have come up with. The Ferret King posted:APUs starting from aircraft battery power are pretty typical right? Nothing about that portion of this process in the 787 is unique? Or is it an especially large APU compared to other airliners? The clever bit there, as brains hinted at, is in the power distribution network. Firstly, because of the way the AC busses are powered, you can and actually will start the APU using external power, which is different. If it's a totally dead aircraft, when you start off battery, it takes the DC battery voltage and inverts it to 115VAC and puts it onto the 235VAC bus that inputs into the CSMC which drives the APU starter/generator...lemme back up... CSMCs are these high power devices that get power from the 235VAC bus, (which is rectified to +/-270VDC), and use that +/-270VDC to drive all the high power loads like hydraulic pumps, air conditioning, engine start, and a few other things. (they can vary the voltage and frequency of that 270V however they need to turn motors) So you're starting off battery, and you're feeding the transformers that feed the CSMCs 115VAC instead of the usual 235VAC. Well that works out to be about half, so you end up turning the starter/generator half speed. Because external power, even though it's also 115VAC, powers the 235VAC busses fully, you get a full speed start off external. I'd love to post a picture of the electrical system synoptic, but there's a chance I'd get in trouble for it so I'd rather not for now.
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# ? Nov 2, 2013 14:36 |
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Ferremit posted:Im kinda surprised that it took over 3 minutes for the fire trucks to arrive- you'd expect that as soon as someone says "Fuel leak" they'd be notified and be on scene as the aircraft was pulled up- If they had been there earlier there wouldnt have been anywhere near the level of flamage. Adding to what Ferret King said, the fuel leak wasn't noticed until the ground crew spotted it after the aircraft parked and idled it's engines. The air crew were completely oblivious to it prior to, as it just happened on the taxi way. So either way, the aircraft will have arrived before the ground emergency crews.
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# ? Nov 2, 2013 14:59 |
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Linedance posted:Excellent description, much better than what I would have come up with.
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# ? Nov 2, 2013 15:47 |
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grover posted:What's the distribution voltage? Does it use aluminum cabling with conventional insulation, or something more exotic? Isn't all that cabling really heavy at 120/235V? it's a modular sort of architecture, so instead of running a power wire out to everything that needs it from lets say the forward E+E, the main power stuff for heavy users is in the aft E+E, close to the loads. Power is also run to remote power distribution units all over the aircraft, which in turn distribute to the loads. So in reality although the power cables might be bigger, there's a hell of a lot less of them. Add to that everything communicating on databuses, and you don't need anywhere near the amount of discretes either. (This bit isn't so much revolutionary, as Embraer and the a380 do similar things).
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# ? Nov 2, 2013 16:07 |
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Polymerized Cum posted:Sometimes. Other times not. Hahaha, my best friend is a pilot in Alaska and at one point he called me (I live in Portland) from roughly 10,000ft while flying a C208 around Mt. McKinley. We had a clear if noisy conversation. Technology, man. brains posted:Basically, traditional turbine aircraft design (and by traditional I mean drat near every design for nearly 60 years is based on this) involves pneumatically-driven starter motors geared to the engine driveshaft. Bleed air, which is air siphoned from a turbine engine after it's been compressed, is used to drive the starters which in turn spins the driveshaft of the turbofan, drawing in air and causing enough compression to start. This bleed-air can come from the other engine, a start cart (on older designs), and most commonly from the APU. Thank you! I do remember watching a lot of those jet engine detail videos on YouTube and I've used GPUs/Start carts as a line service tech for a couple of years, so this all makes a lot of sense. 1.5 megawatts, jesus. SyHopeful fucked around with this message at 17:22 on Nov 2, 2013 |
# ? Nov 2, 2013 17:16 |
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Mistayke posted:That's where I live! Lenny's Clam Bar 4LYFE! Lenny's and New Park pizza I miss terribly. The food in LI is god awful compared to even what is in HB!
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# ? Nov 2, 2013 17:17 |
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Linedance posted:Excellent description, much better than what I would have come up with. Google image serach 787 VFSG. Theres quite a bit out there thanks to the battery issue. There is so much in the electrical system on this airplane. Makes troubleshooting engine not starting difficult sometimes.
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# ? Nov 2, 2013 17:30 |
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Polymerized Cum posted:Sometimes. Other times not. I had a couple of bars at 30k feet in a C-17 as we crossed from Canada into the US near the Great Lakes, and followed our progress on the map. Signal strength wasn't a problem.
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# ? Nov 2, 2013 17:49 |
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Some charts & info on the 787 electrical system in this pdf: http://dibley.eu.com/documents/B787SystemsandPerf-GeorgeBeyle-31mar09.pdfGodholio posted:I had a couple of bars at 30k feet in a C-17 as we crossed from Canada into the US near the Great Lakes, and followed our progress on the map. Signal strength wasn't a problem.
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# ? Nov 2, 2013 18:05 |
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I turned on the FM radio on my iPod Nano last year somewhere over Chicago at cruise altitude and amazingly I was able to pick up stations.
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# ? Nov 2, 2013 19:50 |
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My airline nightmare is having someone yelling to their friends and family every 45 minutes, "hey I got a bar, check if yours has any more! Maybe we can call ahead and tell them we're going to arrive at the exact time the airline posted!". It's bad enough trying to go to sleep with someone furiously tapping on their smartphone with the "clinking" still enabled and cranked to max, but having to deal with regular poo poo that I hear on buses, trains and subways would be loving hell for +12 hours.
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# ? Nov 2, 2013 21:10 |
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I uploaded the first video I mentioned earlier, it's the F-5 Freedom Fighter doc. https://www.youtube.com/watch?v=ZMhByYUPfYA If any of you guys are interested in seeing the rest, I'll start working on them later.
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# ? Nov 2, 2013 23:19 |
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grover posted:Some charts & info on the 787 electrical system in this pdf: http://dibley.eu.com/documents/B787SystemsandPerf-GeorgeBeyle-31mar09.pdf Enough to follow us on the map app on an old iphone 3G. It was only when I held the phone up to the window that I could get anything, though. D C posted:I turned on the FM radio on my iPod Nano last year somewhere over Chicago at cruise altitude and amazingly I was able to pick up stations. If you think about it, you're only 6 miles up or so.
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# ? Nov 3, 2013 00:18 |
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Q_res posted:I uploaded the first video I mentioned earlier, it's the F-5 Freedom Fighter doc. Of course! do it
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# ? Nov 3, 2013 00:37 |
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Well, does anyone have a preference for which one I do next? I've got F-84 Thunderjet, F-86 Sabre, F-104 Starfighter and F-105 Thunderchief. I'll probably do one tomorrow, maybe one sometime during this week and then next weekend finish off the last two.
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# ? Nov 3, 2013 00:47 |
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Q_res posted:Well, does anyone have a preference for which one I do next? I've got F-84 Thunderjet, F-86 Sabre, F-104 Starfighter and F-105 Thunderchief. I'll probably do one tomorrow, maybe one sometime during this week and then next weekend finish off the last two. I vote -84 or -104.
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# ? Nov 3, 2013 00:54 |
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Q_res posted:Well, does anyone have a preference for which one I do next? I've got F-84 Thunderjet, F-86 Sabre, F-104 Starfighter and F-105 Thunderchief. I'll probably do one tomorrow, maybe one sometime during this week and then next weekend finish off the last two. -104, then -105.
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# ? Nov 3, 2013 01:36 |
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Q_res posted:Well, does anyone have a preference for which one I do next? I've got F-84 Thunderjet, F-86 Sabre, F-104 Starfighter and F-105 Thunderchief. I'll probably do one tomorrow, maybe one sometime during this week and then next weekend finish off the last two. F-105, then F-84.
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# ? Nov 3, 2013 01:50 |
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Visited Warner Robins Air Museum during Guard Weekend, been meaning to do it, glad I did.
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# ? Nov 3, 2013 01:58 |
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CommieGIR posted:Visited Warner Robins Air Museum during Guard Weekend, been meaning to do it, glad I did. What the hell am I looking at here?
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# ? Nov 3, 2013 03:22 |
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Goddamn that 707 is regal as gently caress.
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# ? Nov 3, 2013 03:40 |
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CroatianAlzheimers posted:What the hell am I looking at here? Some kind of drone or missile in front of a Jolly Green, it looks like. Loving those camel marks on the Spectre, though.
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# ? Nov 3, 2013 03:45 |
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CroatianAlzheimers posted:What the hell am I looking at here? A Ryan Firebee target/reconnaissance drone, parked in front of an HH-3 Jolly Green Giant.
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# ? Nov 3, 2013 03:45 |
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Fuuuck I passed this three times and normally I'm a continent away. Coulda woulda shoulda.
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# ? Nov 3, 2013 03:48 |
D C posted:I turned on the FM radio on my iPod Nano last year somewhere over Chicago at cruise altitude and amazingly I was able to pick up stations. ADFs operate in the same frequency range as AM radios. During training we didn't have any NDB's nearby but we needed to practice ADF work so we used the local AM station as a navaid. The station had a bunch of those bashit crazy conservative radio hosts, I'm suprised they never talked about all the airplanes circling their station monitoring their "beacon of truth." You can also use them to "listen" to lightning which is pretty bad rear end when you're flying next to a line of storms at night and the lightning syncs up to the static.
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# ? Nov 3, 2013 03:59 |
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KodiakRS posted:ADFs operate in the same frequency range as AM radios. During training we didn't have any NDB's nearby but we needed to practice ADF work so we used the local AM station as a navaid. The station had a bunch of those bashit crazy conservative radio hosts, I'm suprised they never talked about all the airplanes circling their station monitoring their "beacon of truth." The AM band has a much, much longer range than the FM band.
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# ? Nov 3, 2013 04:04 |
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Space Gopher posted:A Ryan Firebee target/reconnaissance drone, parked in front of an HH-3 Jolly Green Giant. Ah, okay. Thanks. It's been a long day here and I stared and stared at that image trying to make sense of it.
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# ? Nov 3, 2013 04:11 |
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holocaust bloopers posted:Goddamn that 707 is regal as gently caress. I'm thinking that may actually be a C-135. The door is in the wrong place for a 707.
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# ? Nov 3, 2013 05:31 |
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# ? May 25, 2024 03:21 |
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CroatianAlzheimers posted:Ah, okay. Thanks. It's been a long day here and I stared and stared at that image trying to make sense of it. Yeah for a second it looked like some really hosed up helicopter.
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# ? Nov 3, 2013 06:07 |