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| Thread ID: 64128 | 2005-12-04 07:01:00 | Sunday night Brain Bender - Airplane Physics | miknz (3731) | PC World Chat |
| Post ID | Timestamp | Content | User | ||
| 410082 | 2005-12-05 17:44:00 | Me pilot mate rang me a few minutes after I posted last night, I am a believer now it flys, it flys. The wheels mean jack **** | plod (107) | ||
| 410083 | 2005-12-05 19:05:00 | 120 posts in this thread. Amazing! Has anyone taken the trouble to take an updated count of the "flies" and "no flies"? |
JJJJJ (528) | ||
| 410084 | 2005-12-05 19:12:00 | As one last effort, non-believers just try this simple experiment: Take a model car with free turning wheels. not wheels connected to a motor or friction drive. Place car on a sheet of card. Hold one end of card with one hand , place finger tip of other hand against car. Pull card backwards and forwards underneath the car. Notice that puffteenth of stuff-all force is required to stop the car moving. What little effort is required is just the wheel bearing friction. It should not take any more brain power to get to the next step of seeing that a moveable runway under a plane could be moved backwards or forwards and only a small force required to stop the plane moving, just that due to wheel bearing friction. And then only a very small neuron effort to start the engines and take off :thumbs: |
Terry Porritt (14) | ||
| 410085 | 2005-12-05 19:50:00 | As one last effort, non-believers just try this simple experiment: Take a model car with free turning wheels. not wheels connected to a motor or friction drive. Place car on a sheet of card. Hold one end of card with one hand , place finger tip of other hand against car. Pull card backwards and forwards underneath the car. Notice that puffteenth of stuff-all force is required to stop the car moving. What little effort is required is just the wheel bearing friction. It should not take any more brain power to get to the next step of seeing that a moveable runway under a plane could be moved backwards or forwards and only a small force required to stop the plane moving, just that due to wheel bearing friction. And then only a very small neuron effort to start the engines and take off :thumbs: That just makes no sense at all :confused: |
Greg (193) | ||
| 410086 | 2005-12-05 20:55:00 | Plod, I am delighted that you pilot mate has confirmed that the plane will fly. Otherwise, I was going to have to ask you what Airline he flew for. :D Personal safety reasons you know. ;) (“Risk Management” to some of you) |
B.M. (505) | ||
| 410087 | 2005-12-05 21:14:00 | Plod, I am delighted that you pilot mate has confirmed that the plane will fly. Otherwise, I was going to have to ask you what Airline he flew for. :D Personal safety reasons you know. ;) (“Risk Management” to some of you) hes a private pilot, he answered the question without really thinking about it |
plod (107) | ||
| 410088 | 2005-12-05 21:30:00 | It's a hypothetical situation mate - too many people aren't getting the essence of the problem . If people can't understand the question properly they really shouldn't debate the answer . You certainly said a mouthful there Greg . Ignorance of aerodynamics and the principles of flight are the major barrier, plus an inability to understand that the principles of flight relate to air and thrust, not the runway or hypothetical movement of the ground the plane takes off from . Speed of the surrounding air and the level of thrust available are the only criteria that matter in this question . The connection to the ground is through virtually zero-friction and zero rolling-resistance wheels . The runway can do what it likes . The ability to fly depends solely on aerodynamics and reaction forces (thrust) . The inteface with the ground simply provides a means of moving while on the ground, and a relatively friction-free transport mechanism to enable the former factors to reach the AIR speed necessary to generate lift . Ground speed and airspeed are two different things as has been previously pointed out . In a very high headwind, a plane can have zero or even negative ground speed . The friction of freely rotating wheels on a runway is insignificant, so whether the ground stands still, moves forward or moves backward is totally irrelevant . Three thoughts: What do you think would happen if a plane flew in and landed on this hypothetical and very mobile reverse-runway while the first plane was trying to take off? Humour me and accept that the runway is long enough for both planes to use it simultaneously . Would it lose the power of flight the instant its wheels touched the deck? What do you think would happen if the runway ran forwards instead of backwards and a plane flew in and landed, and the pilot applied the brakes? Suppose it was a normal runway but built inside a ginormous wind-tunnel . Same plane, ordinary runway . The wind-tunnel controls are programmed to match the rolling speed of the wheels with an equivalent tail-wind . Will the plane achive lift-off? Sometimes looking at a question from several other perspectives helps to clear your thinking . The plane can fly, it is as simple as that . Cheers Billy 8-{) |
Billy T (70) | ||
| 410089 | 2005-12-05 21:46:00 | One day Billy you'll rent an original thought. Don't you know sarcasm when you see it Greg? Only ninja could or would inject crap into a simple thread like this, and it seems, only you would follow. Cheers Billy 8-{) :D |
Billy T (70) | ||
| 410090 | 2005-12-05 21:56:00 | OK, here's the score at present, taken at 128 posts, counting everybody once only, and taking flip-floppers at their most recent opinion. Plane will fly = 21 Plane won't fly = 12 Conscientious objectors = 1 It seems that commonsense and aeronautical principles have carried the day. Cheers Billy 8-{) |
Billy T (70) | ||
| 410091 | 2005-12-05 22:22:00 | OK, here's the score at present, taken at 128 posts, counting everybody once only, and taking flip-floppers at their most recent opinion. Plane will fly = 21 Plane won't fly = 12 Conscientious objectors = 1 It seems that commonsense and aeronautical principles have carried the day. Cheers Billy 8-{) I don't appreciate being called a flip flopper :blush: |
plod (107) | ||
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