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In aviation, altitudes are in feet, distances in nautical miles, speed in knots (nautical miles per hour).
To be fair: 1. The nautical mile is an SI derived unit, now fixed at 1852 meters. 2. It's a more useful unit than the kilometer for long-distance navigation due to its historical definition in terms of arc along a line of latitude making it easy to work with on charts.
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A lightweight paragliding set can be as light as 3 kg these days, and experienced pilots can travel 200+ kilometers regularly with a tiny bit heavier set (say 8 kg).
Paragliding requires ascending currents to maintain or gain altitude, IOW you're always going downwards relative to the surrounding air mass. Birds don't (although they obviously do know how to use it for the cheap). I think maybe the GP is more amazed about the (self-) generated lift and assorted scale. Seems like humans have a thing for hurling self-propelled heavy metal boxes at ridiculous speeds, whether on groun…
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Yeah I'm pretty sure that's the first rule that goes out the window when you're on a private jet.
There's a reason that people with money and power don't always experience good outcomes. Sure, you can do what you like on your jet, and therefore expose yourself to risk that most people never experience. Likewise skiing off-piste or a number of other equally silly activities that you can do, but absolutely shouldn't.
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Probably they have a different idea about risk management than more risk-averse people. Worrying a lot about very low probability events is not compatible with the risk-taking typically required to make a lot of money. After all millionaires are largely a "survivor club" filtered from high risk appetite workaholics.
>millionaires are largely Pedantic, but. Families with $1m net worth are largely late-middle-aged (newly retired) salary workers with paid-off mortgages on their median-priced houses in suburban flyover country, plus ~40 years of 401k contributions and capital gains. They drive Toyotas and fly economy for their 1-2 yearly vacations because that's what left when the 15% 401k contribution, mortgage on 3bd house, childr…
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If you recall Boyle's Law from high school physics - Temperature is proportional to pressure. Aircraft wings generate an intense area of low pressure over the top of the wing (which is what essentially generates the lift). This low pressure area is magnified when flaps and slats are deployed. On a humid day, the lowering of the pressure over the wings can basically force the air temperature at that point to lower and…
Every once in a while I have to re-realize how amazing this phenomenon is. The only thing in nature that flies are birds which weigh a few ounces. Nothing human-scale flies. Cars don't fly. Yet, the flying machines we decide to build weigh a million pounds and fly simply by going fast until the air lifts them up . That is some ludicrous black magic.
"and then he said, 'ounces'"
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True.I would think this would be more of a problem for people from US states where wearing a seatbelt is not mandatory. In other parts of the world (with more sense) such as Europe, Australia, we're conditioned to always using it due to strict enforcement and as such it's not such a novelty.
Speaking as someone who has actually done seatbelt enforcement, (I worked as a cop for a year after college before getting into software development,) catching people who aren't wearing their seatbelts is really, really hard. Each seatbelt ticket written probably takes ~30 minutes of time for the issuing officer.
The physics of this are insane. Then again, by my calculation the A380 displaces roughly 11 million cubic feet of air per second at the max landing weight.
Though note that a box around a cruising A380 at 827 feet per second * 79 feet tall * 262 feet wide is itself 17 million cubic feet.
The A380 is a lot more like 3 boxes (based on A380-800: http://www.airbus.com/fileadmin/media_gallery/files/tech_dat...):
1) A fueselage box with a cross section of 2067 ft^2
2) A wing box of ~1200 ft^2 (a very broad approximation because of engines, the actual wing box - the part of the plane where the wings meet the fueselage - and the curve of the wings),
3) A tail box with a cross section of 144 ft^2
So a total cross section of ~3411 ft^3 * 827 fps = ~3 million ft^3
Point being, the plane isn't moving 11 million cubic feet just to move forward, it pushes on a little more than a quarter of that directly. These wake effects happen because it's disrupting so much air outside of the zone it actually travels in, mostly below and behind it.
Good video of the same (similar?) effect on a small plane after taking off after an Antonov-2 http://www.youtube.com/watch?v=KXlv16ETueU
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> I'd be interested to see in this thread, who here has actually studied aeronautical engineering I studied Aerospace Engineering (PhD in Aerodynamics), and I stay out of internet conversations over "how" lift is generated. For me it is one of those topics that is just not worth debating. It seems that people get _really_ attached to their personally preferred theory of lift.
Agreed. That is what I have noticed in this thread. Who knew aerodynamics could be as polarising as politics or religion? :P I've contributed all that I wanted to say here, and am happy to bow out now and let the conversation take its course.
I think "It's complicated" and "Why do you need to know?" are often the only appropriate answers, as context is important. I've read some "aerodynamics for pilots" type books that from a research point of view I considered to be, to some degree, wrong. But ultimately they were _right_ in that they taught the pilot exactly what they needed to know.
In a way it reminds me of electricity. I know enough to design and make simple circuitry, but I know electrical engineers and physicists that could run rings around me at both the circuit design level and the "That's not how electricity works, you idiot!" level.
> It's an incredible feeling, > lots of fun > Yes, it can be dangerous, > but it's a risk you can > manage yourself Try meth!
This is hilarious. But for the sake of the internet, I just have to say, no, really, don't actually try meth.
