Originally posted by French Rage
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Business, Economics, and Taxes: Capitalism. Yay? >=(
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"It's as if the Drumpf Administration is made up of the worst and unfunny parts of the Cleveland Browns, Washington Generals, and the alien Mon-Stars from Space Jam."
-aparch
"Scenes in "Empire Strikes Back" that take place on the tundra planet Hoth were shot on the present-day site of Ralph Engelstad Arena."
-INCH
Of course I'm a fan of the Vikings. A sick and demented Masochist of a fan, but a fan none the less.
-ScoobyDoo 12/17/2007
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https://twitter.com/CNN/status/1380497176741175296
Boeing has announced a new problem with the troubled 737 Max plane — this time, the issue is with its electrical system.Last edited by Handyman; 04-09-2021, 10:29 AM."It's as if the Drumpf Administration is made up of the worst and unfunny parts of the Cleveland Browns, Washington Generals, and the alien Mon-Stars from Space Jam."
-aparch
"Scenes in "Empire Strikes Back" that take place on the tundra planet Hoth were shot on the present-day site of Ralph Engelstad Arena."
-INCH
Of course I'm a fan of the Vikings. A sick and demented Masochist of a fan, but a fan none the less.
-ScoobyDoo 12/17/2007
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"Airlines need to verify that one of the components of the plane's electrical system is sufficiently grounded."
They need to make sure the electrical system is grounded so that the airplane is not grounded...If you don't change the world today, how can it be any better tomorrow?
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The 737 Max was first grounded, after the crashes, the day I was on one from the west coast to Kona. For some reason we all knew about it before takeoff, that it would be its last flight. Which seems weird now.Huskies are very intelligent and trainable. Huskies make an excellent jogging companion, as long as it is not too hot. Grooming is minimal; bathing is normally unnecessary.
USCHO Fantasy Baseball Champion 2011 2013 2015
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Originally posted by St. Clown View Post
Were you approved for 2 or 3 million?
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Originally posted by LynahFan View Post"Airlines need to verify that one of the components of the plane's electrical system is sufficiently grounded."
They need to make sure the electrical system is grounded so that the airplane is not grounded...
How can the electrics in an airplane in flight be grounded?
I am mortified by how dumb this is. I'll hang my head in shame and listen.Cornell University
National Champion 1967, 1970
ECAC Champion 1967, 1968, 1969, 1970, 1973, 1980, 1986, 1996, 1997, 2003, 2005, 2010
Ivy League Champion 1966, 1967, 1968, 1969, 1970, 1971, 1972, 1973, 1977, 1978, 1983, 1984, 1985, 1996, 1997, 2002, 2003, 2004, 2005, 2012, 2014, 2018, 2019, 2020
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Originally posted by Kepler View Post
I have a short bus E&M question.
How can the electrics in an airplane in flight be grounded?
I am mortified by how dumb this is. I'll hang my head in shame and listen.
Cornell '04, Stanford '06
KDR
Rover Frenchy, Classic! Great post.
iwh30 I wish I could be as smart as you. I really do you are the man
gregg729 I just saw your sig, you do love having people revel in your "intelligence."
Ritt18 you are the perfect representation of your alma mater.
Miss Thundercat That's it, you win.
TBA#2 I want to kill you and dance in your blood.
DisplacedCornellian Hahaha. Thread over. Frenchy wins.
Test to see if I can add this.
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Marx was wrong. Most of the proles like wage slavery just fine.
Amazon workers in Alabama on Friday rejected unionization, a major victory for the e-commerce giant in a high-profile, high-stakes battle that will have ripple effects across the nation for workers and the labor movement.
Amazon, the second-largest private employer in the United States behind Walmart, has successfully staved off attempts to unionize at its U.S. warehouses for more than two decades. The vote Friday, in which the company won over workers at its year-old Bessemer, Ala., warehouse by more than a 2-to-1 margin, was a massive blow for labor organizers who saw the facility — and Amazon broadly — as ripe for organizing.
A union victory could have triggered a wave of organizing drives at other Amazon warehouses, potentially giving workers more flexibility to demand concessions from the company on things such as breaks, safety and the pace of work. But the loss throws cold water on that, and allows Amazon to add and cut staff at its warehouses as it wants.Cornell University
National Champion 1967, 1970
ECAC Champion 1967, 1968, 1969, 1970, 1973, 1980, 1986, 1996, 1997, 2003, 2005, 2010
Ivy League Champion 1966, 1967, 1968, 1969, 1970, 1971, 1972, 1973, 1977, 1978, 1983, 1984, 1985, 1996, 1997, 2002, 2003, 2004, 2005, 2012, 2014, 2018, 2019, 2020
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They’re in Alabama. Not only do they have a company propaganda to overcome, but they also have decades of anti-labor union sentiment. It’s something that would take time should they choose to continue pursuing it."The party told you to reject the evidence of your eyes and ears. It was their final, most essential command." George Orwell, 1984
"One does not simply walk into Mordor. Its Black Gates are guarded by more than just Orcs. There is evil there that does not sleep, and the Great Eye is ever watchful. It is a barren wasteland, riddled with fire and ash and dust, the very air you breathe is a poisonous fume." Boromir
"Good news! We have a delivery." Professor Farnsworth
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This isn't 1955...they have access to information and Amazon wouldn't risk retaliation. Sorry my heart doesn't bleed for them."It's as if the Drumpf Administration is made up of the worst and unfunny parts of the Cleveland Browns, Washington Generals, and the alien Mon-Stars from Space Jam."
-aparch
"Scenes in "Empire Strikes Back" that take place on the tundra planet Hoth were shot on the present-day site of Ralph Engelstad Arena."
-INCH
Of course I'm a fan of the Vikings. A sick and demented Masochist of a fan, but a fan none the less.
-ScoobyDoo 12/17/2007
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Thing is, in Alabama, these are probably really good, relatively high-paying jobs. You can forgive the workers for not wanting to potentially end up antagonizing that employer and suffering consequences.What kind of cheese are you planning to put on top?
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Originally posted by rufus View PostThing is, in Alabama, these are probably really good, relatively high-paying jobs. You can forgive the workers for not wanting to potentially end up antagonizing that employer and suffering consequences.Cornell University
National Champion 1967, 1970
ECAC Champion 1967, 1968, 1969, 1970, 1973, 1980, 1986, 1996, 1997, 2003, 2005, 2010
Ivy League Champion 1966, 1967, 1968, 1969, 1970, 1971, 1972, 1973, 1977, 1978, 1983, 1984, 1985, 1996, 1997, 2002, 2003, 2004, 2005, 2012, 2014, 2018, 2019, 2020
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Originally posted by Kepler View Post
I'm sure they were made to understand that if they unionized they would close the facility. Ownership doesn't need to smash heads anymore -- they play the rubes off against each.
(asking legitimately I never understood Labor Law)"It's as if the Drumpf Administration is made up of the worst and unfunny parts of the Cleveland Browns, Washington Generals, and the alien Mon-Stars from Space Jam."
-aparch
"Scenes in "Empire Strikes Back" that take place on the tundra planet Hoth were shot on the present-day site of Ralph Engelstad Arena."
-INCH
Of course I'm a fan of the Vikings. A sick and demented Masochist of a fan, but a fan none the less.
-ScoobyDoo 12/17/2007
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Originally posted by French Rage View Post
If I'm understanding this correctly, you basically try to pass the current to the outside of the body so it can dissipate into the atmosphere: https://monroeaerospace.com/blog/how...ally-grounded/
This is more-or-less impossible to explain without a whiteboard, but I'll try to get a few points across:
1. Your car is also not "grounded" to the earth (the only thing touching the ground are 4 pretty darn good insulators), so there's nothing all that special about airplanes in that regard.
2. While an airplane is in flight, or while your car is driving down the road, it definitely can build up static electricity that puts the vehicle at a different voltage from the ground. That either dissipates gradually over time, with electricity "leaking" very slowly via those highly resistive paths (via the tires or directly through the air - neither are perfect insulators), OR, when something does provide a conductive path from the vehicle to the ground, the electricity will discharge rapidly in a "static electricity" spark - exactly the same as when you scuff your feet on the carpet (building up charge on your body) and then touch a conductive doorknob (dissipating that charge very rapidly). You don't know this, but every single time your airplane comes into the gate, a ground crew member attaches a conductive wire to the airplane to do exactly that, so that nobody and no equipment gets sparked when the jetway touches the airplane or people disembark the airplane. If you drive a long distance, the same thing can happen to your car, and when you step out, you will become that grounding path and there will be a spark to your shoe - but you don't feel it, because of your shoe. This is why it is not a good idea to climb back into your vehicle while you're pumping gas - when you climb back out, there could be a spark. Sometimes you'll see trucks that carry explosive materials have a chain dragging on the ground, which is there to dissipate static electricity continuously, as soon as it is generated, so that you never get one big spark.
3. When we talk about "the" voltage of the airplane/car, that's a bit oversimplified, because of course there are many things at different voltages all over the aircraft. However, in general, what happens is that aircraft designers make sure that all the big metal pieces of the airplane (ribs, spars, skins, engines, etc) are electrically bonded together and that "chassis" becomes the "ground" for the airplane (car designers do the same thing). The electrical generator on board the aircraft has its negative terminal tied to the chassis, and then its positive terminal is the "hot" side that provides power out to all the devices on the aircraft that run on electricity. if you have a 270V generator, then your positive voltage will always be 270V above the chassis (whose voltage relative to the earth floats, as we've already talked about). Electricity leaves the generator, goes through various switches (remember this, it becomes important in a minute) and circuit breakers and finally to a pump or a flight computer or a cockpit display or whatever. Those devices "use up" the energy contained in the electrons flowing through it, and then return those electrons to the chassis and therefore to "ground" terminal of the generator, completing the circuit.
4. Those switches and circuit breakers in the loop are not all that different from the circuit breaker panel in your house - a "trunk" line of major power comes in from the generator, and then the electricity gets distributed out via the individual breakers to many different circuits. The biggest difference for an airplane circuit breaker panel is that the whole thing is computer controlled, so a control program can command individual circuit breakers to open and close (so long as they haven't already tripped due to over-current), which is how most devices on the airplane get turned on and off. So that "circuit breaker panel" is a pretty complex device in its own right. With lots of complexity, comes lots of failure modes. If "stuff" happens inside the box and electricity tries to go where it shouldn't, then that box needs to have a way to release those electrons safely back to the chassis, or too much electricity will build up inside the box. That eventually will get out, but if you don't have a designed-in path, then where it ends up going is pretty unpredictable, and chances are that it will end up putting more current through parts of the device than they can handle and those parts will burn. From what I can tell from news reports I've read (I have no insider information), 737MAX has an issue with the grounding of their circuit breaker panel, such there are probably a few bizarre, extremely improbable failure modes where the box would end up not able to dissipate the current back to the chassis. Who knows how they discovered this issue now, but these things are constantly being re-visited as airlines have trouble in the field with X or Y, and a new engineer gets asked to take a look at something and that new set of eyes sees something that the prior one did not.
5. Note that none of what I've talked about so far has anything to do with lightning. A lightning event (a huge current of electricity entering from outside the airplane) is nothing like what I described above, which would be called an "electrical fault" event. An electrical fault is simply when a piece of electrical equipment on board the airplane puts a moderate electrical current (that you generated intentionally in your generators) somewhere that it shouldn't be. When an airplane gets hit by lightning, the whole name of the game is to be sure that your skin (where the lightning enters) is electrically bonded so tightly to the chassis that the electricity hits the skin, immediately takes the path of least resistance through the chassis, and then exits the airplane at a different point on the skin. Lightning never "stops" at an airplane - it always just passes through. The idea is that you only want it to pass through the skins and the chassis, and not through any of the computers or other sensitive electrical equipment. If you do it well, a massive lightning strike can flow through the chassis, and none of the equipment (which all uses that chassis as a ground) will even notice - the equipment simply continues to "float" at +270V (or whatever your generator produces) above the chassis throughout the event. The chassis voltage will rise and fall as the lightning passes through, but the equipment won't care - it just floats along for the ride.
Well, that was more than I meant to write, but I hope it helped and was maybe even a tiny bit interesting in places....If you don't change the world today, how can it be any better tomorrow?
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