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Comment: Re:As long as it's not windy (Score 1) 131

by michelcolman (#49386641) Attached to: World's Largest Aircraft Seeks Investors To Begin Operation

If an airship can fly at 80 kts (which is very fast indeed for an airship), it will *not* require 100% more power to increase its speed by 5 kts. That's just preposterous. Drag probably increases with the square of the speed just like (roughly) for airplanes. Obviosuly an airship will have more drag at any speed because of its huge frontal area, but the shape of the drag curve will not be drastically different. Certainly not to the point of requiring twice as much power for 5% more speed.

So the comparison with a small plane that has a cruising speed of 80 kts is in fact perfectly valid.

Comment: Re:As long as it's not windy (Score 1) 131

by michelcolman (#49384941) Attached to: World's Largest Aircraft Seeks Investors To Begin Operation

The GGP was talking about making headway against a strong headwind. In a steady headwind, any airplane with an 80 kt cruising speed will see the same effect from that headwind. The fact that the airship happens to be really big does not change the fact that it simply gets the same wind speed vector added to its airspeed.

Gusts would just make the flight more turbulent, but would not change the average speed much.

Comment: Re:Nintendo "Corporate Social Responsibility": (Score 1) 99

by michelcolman (#49384533) Attached to: Mario 64 Remake Receives a DMCA Complaint From Nintendo

There are legal reasons requiring companies to react to violations of their copyright and trademarks, since they may otherwise legally lose them. However, they could have just reacted with "place a notice on your website that we own all the trademarks and copyrights but gave you explicit permission to keep this excellent remake on your website as long as it's limited to part of the first level."

It's more publicity for their game and may actually lead to more sales from people trying out the web version and then buying the real thing. But alas, lawyers don't think that way.

Comment: Re:As long as it's not windy (Score 3, Interesting) 131

by michelcolman (#49384489) Attached to: World's Largest Aircraft Seeks Investors To Begin Operation

and making much headway against a strong headwind is going to take a lot of power with that much windage.

Just to clarify a common misconception about wind and "windage": many people seem to think that wind affects airplanes the same way as cars, needing more power to keep moving in a headwind. That is not the case. Airplanes fly in the air, they don't care about the ground. If that air happens to be moving, they move along with it. It's an extra speed vector to be added to airspeed, nothing more. Like walking on a conveyor belt, you don't get more or less tired (per minute) when walking at the same pace, but you do move more quickly or slowly depending on the direction of the belt. Airplanes don't "feel" crosswinds either, they just fly straight through the air, but end up moving sideways relative to the ground because of the addition of the two speed vectors.

The only reason why airplanes often use more power in a headwind, is because the pilot may elect to fly faster to (partially) compensate for the wind. An 80 kt airship in a 40 kt headwind will only have a ground speed of 40 kt, so the pilots may well choose to increase power to get a higher ground speed. The economic optimum speed for total fuel consumption over a given distance is at a higher airspeed in a headwind, and at a lower airspeed in a tailwind, simply because the math works out that way: the airship in a 40 kt headwind will get a 10% boost in ground speed (44 i.o. 40) for only a 5% boost in airspeed (84 i.o. 80), which shifts the economic optimum speed upward. But fuel consumption per minute at the same airspeed is the same no matter what the wind is.

So headwinds don't affect the airship any more than it affects a small plane with a cruising speed of 80 kts.

Changing gusts of wind are a different matter, of course. The plane or airship definitely does "feel" those.

Comment: Re:Take a bus, sometimes (Score 3, Insightful) 322

by michelcolman (#49377429) Attached to: Poverty May Affect the Growth of Children's Brains

I think that's just a small part of it, I know plenty of rich people who give their children junk food, and poor people who make a big effort to only buy healthy stuff.

I think the researchers simply got cause and effect mixed up.

People with smaller brains tend to end up with a lower income and get less education. And their kids end up inheriting the smaller brain from their parents.

Obviously that doesn't mean than all poor people are stupid, just that statistically, people with larger brains tend to do better in life, and this results in a correlation when you look at a sufficiently large number of people.

Makes a lot more sense to me.

Comment: Re:Protected relationships (Score 1) 379

by michelcolman (#49360307) Attached to: Modern Cockpits: Harder To Invade But Easier To Lock Up

The real reason for the secrecy of confessions is much cleverer.

If you tell people they should confess their sins, and their secrets are safe with the priest, the end result is that the priest knows all the secrets of the village. Need I say more? The local priest used to be the most powerful person in the village, subtly using his knowledge to play the people and instill fear in them. Brilliant idea.

Comment: Re:Ummmm ... duh? (Score 1) 379

by michelcolman (#49360285) Attached to: Modern Cockpits: Harder To Invade But Easier To Lock Up

In the US there is no true doctor-patient confidentiality when it comes to pilots. The medical certificate application requires a pilot to list all visits to a doctor in the last three years and the reason (item 19). Item 18 asks if you have ever in your life been diagnosed as having a plethora of conditions, including "(m) mental disorders of any sort; depression, anxiety, etc."

And it's obviously completely impossible to give false answers to those questions. No, never seen a doctor. No depression, nothing, perfectly fine.

Comment: Re:Ummmm ... duh? (Score 1) 379

by michelcolman (#49360255) Attached to: Modern Cockpits: Harder To Invade But Easier To Lock Up

What a wonderful idea, armed pilots in the cockpit :-(

But anyway, even with two unarmed pilots in the cockpit, one of the pilots can still crash the plane if he wants to. It won't be quite as clean as a nice long descent straight into a mountain, but if you just unexpectedly yank the controls down and to one side during approach, the other pilot probably won't have time to do anything about it. Especially on an airbus where they can fight over the controls with the override button (the last to press the override button has controls, so controls could go back and forth indefinitely, making recovery impossible).

And then there's always the crash axe or fire extinguisher. Hey, look at that plane over there... wham.

Of course this kind of action would be much more agressive and less likely to be performed by an introvert depressed person. Locking the door and starting a descent is psychologically easier than physically attacking someone or fighting over the controls. But no safety measure can ever be completely fool proof. People with power can do powerful things, not just in airplanes.

Comment: Re:Ummmm ... duh? (Score 1) 379

by michelcolman (#49360229) Attached to: Modern Cockpits: Harder To Invade But Easier To Lock Up

How long do the pilots hold out when the hijackers slaughter the passengers one by one outside their door, on their camera?

I would immediately make an announcement for everyone to fasten their seatbelts, wait 5 seconds, then create massive "turbulence". We can do -1g and +2.5g, so we can throw the hijackers against the ceiling and back onto the ground hard a few times. Then we can give the signal for the other crew members or passengers to overpower the attackers.

But in no case would we open the cockpit door. If they take over and crash the plane, everyone is dead anyway. So no matter how many people they slaughter in the cabin, that death toll can never be higher than what we'd get if we let them in.

Comment: Re:Ummmm ... duh? (Score 2) 379

by michelcolman (#49360213) Attached to: Modern Cockpits: Harder To Invade But Easier To Lock Up

Fast forward a few years. Depressed cabin crew member, alone with one pilot in the cockpit, hits him in the head with the crash axe which is stored behind the first officer's seat. Or with one of the fire extinguishers.

There's no winning this. If you can't trust the crew members, all bets are off.

IF I HAD A MINE SHAFT, I don't think I would just abandon it. There's got to be a better way. -- Jack Handley, The New Mexican, 1988.

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