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I feel like I've been lied to my whole life
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Sep 1, 2017 19:37
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EightBit posted:Gyroscopic effect takes some serious speed to be noticeable with light bicycle wheels. You can balance a bicycle while barely moving, but gyroscopic effect doesn't become noticeable until you're over 20mph, generally. If you sit on a chair that can spin and you hold a spinning bicycle wheel, you can tilt the wheel to turn the chair.
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Sep 1, 2017 19:50
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The Door Frame posted:I feel like I've been lied to my whole life Also airfoils don't work because "the shape creates a low pressure area above the wing". 
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Sep 1, 2017 20:18
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There is one way that gyroscopic action helps stabilize a bike both pedal and power, as the bike leans the gyroscopic procession adds a steering force that turns into the lean and helps to right it. Between this and the rake and caster it wants to autocorrect and will do so until it is going so slowly the resulting inputs are too dampened or the front tire scrubs or the forks or bars hit the frame. I think the reason a tight headset make hands free riding easier is that it dampens oscillations that would otherwise build.
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Sep 1, 2017 20:18
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xzzy posted:Also airfoils don't work because "the shape creates a low pressure area above the wing".
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Sep 1, 2017 21:12
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Cojawfee posted:If you sit on a chair that can spin and you hold a spinning bicycle wheel, you can tilt the wheel to turn the chair. I tried this with a high-powered leaf blower and didn't go as planned.
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Sep 1, 2017 21:16
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C-Bangin' it 
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The Door Frame posted:I feel like I've been lied to my whole life You have been, about a great many things. Fifty Three posted:Maybe I'm misunderstanding or missing a joke, but per Bernoulli's principle the fast-moving air above the wing exerts less pressure than the slow-moving air under the wing, correct? Thus creating a net force upwards? I'm assuming your point is that there's much more to it than that. You're missing the part about "why would the air move faster over the top part of the wing? What would make it do that?" Also "how do stunt planes fly upside down", and "how does that plane with the KFC buckets for wings fly?" edit: https://www.youtube.com/watch?v=K6geOms33Dk https://www.youtube.com/watch?v=aFO4PBolwFg Darchangel fucked around with this message at 21:22 on Sep 1, 2017 |
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Sep 1, 2017 21:18
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Colostomy Bag posted:I tried this with a high-powered leaf blower and didn't go as planned. You didn't plan on spinning around at high speed about once then flipping over?
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Sep 1, 2017 21:24
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Darchangel posted:You didn't plan on spinning around at high speed about once then flipping over? Not really. I was spinning a bicycle wheel during this escapade.
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Sep 1, 2017 21:37
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Fifty Three posted:Maybe I'm misunderstanding or missing a joke, but per Bernoulli's principle the fast-moving air above the wing exerts less pressure than the slow-moving air under the wing, correct? Thus creating a net force upwards? I'm assuming your point is that there's much more to it than that. I don't know if it is a joke, but if it is, probably in relation to the fact that giant planes like a 747 have a glide slope similar to a brick falling off a roof. An airfoil doesn't matter so much as the engines brute force the plane into the air.
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Sep 1, 2017 21:46
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Cojawfee posted:I don't know if it is a joke, but if it is, probably in relation to the fact that giant planes like a 747 have a glide slope similar to a brick falling off a roof. An airfoil doesn't matter so much as the engines brute force the plane into the air. I think you'll find the 747 glide slope as graceful as a sail plane compared to the Shuttle. Have you seen pics of the Gulfstream training aircraft for training shuttle landing approaches? LOL:  The Shuttle is worse than anything else at atmospheric flying.
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Sep 1, 2017 21:57
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TotalLossBrain posted:
Including the F-105?
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Sep 1, 2017 22:02
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Cojawfee posted:I don't know if it is a joke, but if it is, probably in relation to the fact that giant planes like a 747 have a glide slope similar to a brick falling off a roof. An airfoil doesn't matter so much as the engines brute force the plane into the air. A 747 has a better glide ratio than a Cessna 172. Most airliners have large, efficient wings which lets them glide pretty well. Quick googling: C172 (light piston single airplane): 9:1. It'll go 9 units forward for every 1 unit down. For the big guys: 747-200: 15:1 767: 12:1 777: 19:1 A320: 17:1 Regional jets are about 10:1, Twin turboprops are about 12:1, Bizjets are also around 10:1. Fighters are like bricks. 6:1 for the F-16, 6.5:1 for the F-15, and 5.4 for the F-18. Yeah, the Shuttle is like 1:1 until it flares, then it's only 4:1. It's falling out of the sky. Note that many helicopters autorotate at about 4:1. That's a pretty steep descent, but very controllable stop. babyeatingpsychopath fucked around with this message at 22:12 on Sep 1, 2017 |
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Sep 1, 2017 22:09
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Colostomy Bag posted:Including the F-105? It's even worse than the F-104, which is just an engine with small control fins attached. That thing has a glide ratio of ~5 clean, and ~3 with the gear and flaps down. It used engine bleed air in normal landings to make its glide ratio much better (blown flaps).
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Sep 1, 2017 22:16
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babyeatingpsychopath posted:It's even worse than the F-104, which is just an engine with small control fins attached. That thing has a glide ratio of ~5 clean, and ~3 with the gear and flaps down. It used engine bleed air in normal landings to make its glide ratio much better (blown flaps). If only Ford placed ceramic tiles on the Pinto.
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Sep 1, 2017 22:54
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babyeatingpsychopath posted:It's even worse than the F-104, which is just an engine with small control fins attached. That thing has a glide ratio of ~5 clean, and ~3 with the gear and flaps down. It used engine bleed air in normal landings to make its glide ratio much better (blown flaps). Shuttle is basically mathematical model. The 104 and the 105 were throwing darts at the wall (And and the lawn.) So was the B-58.
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Sep 1, 2017 22:57
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And Shuttle was originally going to glide even worse than that, but the USAF had plans that required bigger wings.
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Sep 1, 2017 22:58
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The "faster / slower air" thing is a misunderstanding of how a plane (flat object, not an airplane) interacts with a fluid it is moving through. It's easier (and truer) to think of objects as "collecting" particles that they're pushing through - if the object collects more particles on one side than the other, it creates a pressure differential in the fluid. The amount of pressure differential between the two sides of the object dictates how much force is trying to move the object towards the lower pressure. This visualization explains lift, downforce, drag, drafting, etc - think of a splitter on the front of a car collecting air on top of it. It shovels up air that wants to escape under the car, which creates pressure that wants to push the splitter down (downforce!), and also to push the car backwards (drag!), and also reduces the air that can escape under the car, which increases the pressure differential between the top of the car and the underside (downforce!). A spoiler creates a disturbance in the airflow so that the car doesn't just push particles up and out of the way, but also scatters them around behind it, which means that more particles end up behind the car than without a spoiler, which means that there is more pressure behind the car than would otherwise be there, which means that there is less of a pressure differential between the front (collecting lots of particles) and the back (in some cases nearly devoid of particles without a spoiler), which reduces drag. Good times, right?
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Sep 1, 2017 23:02
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Spoilers reduce drag they dont add it, an airfoil does i cant think of many that work that way on a car outside of f1 though.
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Sep 1, 2017 23:10
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Shame on everybody for forcing me to post a jalopnik article i hope you are happy. http://oppositelock.kinja.com/wings-spoilers-youre-probably-doing-it-wrong-1665312667
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Sep 1, 2017 23:16
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Colostomy Bag posted:If only Ford placed ceramic tiles on the Pinto. Did somebody mention flying Pintos? 
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Sep 2, 2017 00:03
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PainterofCrap posted:Did somebody mention flying Pintos? Isn’t that the one that was going to be used in The Man with the Golden Gun but then the creator died in a crash so they used a model?
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Sep 2, 2017 00:08
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The important thing to consider is that we are changing the direction and pressure of the air and that creates force. Both things are happening at the same time, so I don't think you can say "no, it's not the bernouille effect," because there is a pressure difference and that pressure difference exerts a force.
jamal fucked around with this message at 00:35 on Sep 2, 2017 |
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Sep 2, 2017 00:33
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Cojawfee posted:If you sit on a chair that can spin and you hold a spinning bicycle wheel, you can tilt the wheel to turn the chair. That's not poo poo compared to the force required to keep you upright.
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Sep 2, 2017 00:42
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DogonCrook posted:Spoilers reduce drag they dont add it, an airfoil does i cant think of many that work that way on a car outside of f1 though. That's what I said, yeah. More pressure behind the car because of spoiled air reduces the front>rear pressure differential and therefore reduces drag.
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Sep 2, 2017 01:29
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babyeatingpsychopath posted:A 747 has a better glide ratio than a Cessna 172. Most airliners have large, efficient wings which lets them glide pretty well. Yeah, this. I don't know where the stories about awful glide slopes for heavies comes from. They make their money by being efficient over long distances, which means low drag airfoils, which directly means better glide ratios. Now with full flaps and the gear down they're probably closer to steinway:1...
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Sep 3, 2017 02:47
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Platystemon posted:Isn’t that the one that was going to be used in The Man with the Golden Gun but then the creator died in a crash so they used a model? It was a model in the movie, but it was an AMC Matador. Most likely inspired by that one, though, since I think that Pinto was the only actual flying car at the time.
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Sep 3, 2017 03:09
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charliemonster42 posted:Now with full flaps and the gear down they're probably closer to steinway:1...
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Sep 3, 2017 03:40
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nmfree posted:Especially if they fly for Careless Air. That's why I keep a piano on my car, to prevent others from falling on it.
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Sep 3, 2017 05:39
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Darchangel posted:It was a model in the movie, but it was an AMC Matador. Most likely inspired by that one, though, since I think that Pinto was the only actual flying car at the time. The directors commentary on that movie says they were going to use a real one, but it ended up crashes shortly before they needed it for filming.
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Sep 3, 2017 10:04
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HandlingByJebus posted:That's what I said, yeah. More pressure behind the car because of spoiled air reduces the front>rear pressure differential and therefore reduces drag. But what if the car is on a treadmill moving the exact same speed as the wheels?
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Sep 3, 2017 12:20
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PainterofCrap posted:Did somebody mention flying Pintos? Ahem 
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Sep 3, 2017 14:17
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Meh......
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Sep 3, 2017 20:57
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Ah, the USMC's new air superioriCAS stealth nuclear fightersub.
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Sep 3, 2017 21:25
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Sep 4, 2017 09:23
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I don't see what's oh
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Sep 4, 2017 09:27
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Jesus, how long did it run like that?
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Sep 5, 2017 19:50
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Well it's out of a big truck (Volvo D16), so probably awhile.
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Sep 5, 2017 21:54
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Sep 7, 2017 08:38
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Tinypic doesn't seem to support SSL, so you'll have to rehost that elsewhere E: 
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Sep 7, 2017 09:53
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