aircraft position calculation
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Nozzles
I'm getting seriously concerned about your lack of theoretical knowledge. It's bloody obvious man, you can't get enough fuel into a Harrier to hover for 24 hrs ......... jeez !!
Sarboy doodahs
Thanks for the Montessori maths lesson but how does that prove the unquestionable logic of Fecks theory that 'if you know where you are not, then you must know where you are' or 'if you don't know where you are then you must know where you are not' Revd Dodgson school of navigation.
I'm getting seriously concerned about your lack of theoretical knowledge. It's bloody obvious man, you can't get enough fuel into a Harrier to hover for 24 hrs ......... jeez !!
Sarboy doodahs
Thanks for the Montessori maths lesson but how does that prove the unquestionable logic of Fecks theory that 'if you know where you are not, then you must know where you are' or 'if you don't know where you are then you must know where you are not' Revd Dodgson school of navigation.
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Posted by sarboyw****r
Judging by the length of your post your social life needs looking at old chap ? 
I don't have the formulae to hand, and I'm not so short of a social life that I need to know it off by heart...
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Ah Whiz,
Such is life on a 24 hour SAR shift such as yesterday that I found myself with nothing better to do at 2200 than answer random questions...
And as for the Montessori maths lesson, well I did pick up a thing or two whilst I was spending your taxes at university! Thanks, they paid for quite a few beers...
Hic!
SBW
Such is life on a 24 hour SAR shift such as yesterday that I found myself with nothing better to do at 2200 than answer random questions...
And as for the Montessori maths lesson, well I did pick up a thing or two whilst I was spending your taxes at university! Thanks, they paid for quite a few beers...
Hic!
SBW
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Chaps. I hope there is more. I have learned far more from this thread than all the rest added together over the last couple of months! As a blunt and thick as a thick thing, I always wondered how those plane thingys stayed in the air, never mind the moving around thing. This is better than Television for Schools ever was! Thanks and much humbler now. 
Nozzles,
Look in your FRCs. That complicated table in there showing engine limitations is the giveaway. The reason for the short time limits operating at lift ratings is just because of earth rotation. If you stay around in the hover for too long, your landing spot will have moved away. It's happened to many a good mate in the past. Mexe pads seem to move faster than most surfaces.
C Hinecap,
To get the full explanation of how the plane thingys stay in the air, you need to read the article first seen in the Wittering View in 1982. The joint authors, Harvey Elling and V T Owen, managed to condense a very technical subject into a form that most could comprehend. Basically, it comes down to conventional aircraft moving fast enough to run into small lighter-than-air creatures called Bernoullis, which tend to stick to the wings. To manoeuvre, flappy bits on the wings (ailerons, spoilers, whatever) are moved, causing the Bernoullis to fall off. In the case of the Harrier, there is another effect when the production of sudden huge volumes of noise under the aircraft causes it to jump up in surprise, though as it gets used to this, it tends to settle back down unless some Bernoullis are collected. Best vertical results are achieved after long periods of conventional flight, when lack of fuel lulls the aircraft into a false sense of security that the noise is about to cease. Then it can really be startled away from the ground. For more details, refer to the eminent aerodynamicists and their original work.
Hope this helps.
Look in your FRCs. That complicated table in there showing engine limitations is the giveaway. The reason for the short time limits operating at lift ratings is just because of earth rotation. If you stay around in the hover for too long, your landing spot will have moved away. It's happened to many a good mate in the past. Mexe pads seem to move faster than most surfaces.
C Hinecap,
To get the full explanation of how the plane thingys stay in the air, you need to read the article first seen in the Wittering View in 1982. The joint authors, Harvey Elling and V T Owen, managed to condense a very technical subject into a form that most could comprehend. Basically, it comes down to conventional aircraft moving fast enough to run into small lighter-than-air creatures called Bernoullis, which tend to stick to the wings. To manoeuvre, flappy bits on the wings (ailerons, spoilers, whatever) are moved, causing the Bernoullis to fall off. In the case of the Harrier, there is another effect when the production of sudden huge volumes of noise under the aircraft causes it to jump up in surprise, though as it gets used to this, it tends to settle back down unless some Bernoullis are collected. Best vertical results are achieved after long periods of conventional flight, when lack of fuel lulls the aircraft into a false sense of security that the noise is about to cease. Then it can really be startled away from the ground. For more details, refer to the eminent aerodynamicists and their original work.
Hope this helps.
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insty66,
A very valid point, sir. In that case the laws of circular motion tell me that the further from the centre (and therefore the surface) of the earth one hovers, the faster one is going. At what altitude would one go supersonic in the hover?
eh?
eh?
A very valid point, sir. In that case the laws of circular motion tell me that the further from the centre (and therefore the surface) of the earth one hovers, the faster one is going. At what altitude would one go supersonic in the hover?
eh?
eh?
Champagne anyone...?
Beroulli's Theorem
noprobs
Your discussion of the Bernoulli, or Bernoullis Kineticus as it is better known at CFS and the Natural History Museum, brings to mind their involvement in the generation of thrust by propellers.
As you are no doubt aware, propeller blades can be quite sharp. Indeed they are sharp enough to damage or even kill Bernoullis. Over the years Bernoullis have come to recognise this fact and as such as have developed an inate fear of them. The sight of a turning propeller will cause any Bernoullis ahead of it to vacate the area. The speed with which they move is enough to briefly generate a vaccuum. As nature abhors a vacuum, the propeller and the associated mass of aircraft is then drawn foward into the space created by the departing creatures. The more Bernoullis you can scare, the faster forward you go.
Bernoulli scaring can be increased by adding more blades or making them sharper. Pioneering aviators found it difficult to attain much speed as their propellers weren't very sharp and the Bernoullis had yet to develop a fear of them.
Interestingly, even a stationary prop can generate fear in local Bernoullis. As the aircraft is parked and chocked it can't be drawn forward by the departing Bernoullis. This leads to a localised thinning of the air around the aircraft. The effects of this rarefied atmosphere can be seen to be best effect on, say, an early morning at Akrotiri. The crew may appear unsteady on their feet or drowsy and some of them be lying on the pan, under the wing, apparently unconscious. The younger, more inexperienced co-pilots often suffer the worst from this, what is basically a form of altitute sickness, and may often be seen vomiting on the nosewheel.
Your discussion of the Bernoulli, or Bernoullis Kineticus as it is better known at CFS and the Natural History Museum, brings to mind their involvement in the generation of thrust by propellers.
As you are no doubt aware, propeller blades can be quite sharp. Indeed they are sharp enough to damage or even kill Bernoullis. Over the years Bernoullis have come to recognise this fact and as such as have developed an inate fear of them. The sight of a turning propeller will cause any Bernoullis ahead of it to vacate the area. The speed with which they move is enough to briefly generate a vaccuum. As nature abhors a vacuum, the propeller and the associated mass of aircraft is then drawn foward into the space created by the departing creatures. The more Bernoullis you can scare, the faster forward you go.
Bernoulli scaring can be increased by adding more blades or making them sharper. Pioneering aviators found it difficult to attain much speed as their propellers weren't very sharp and the Bernoullis had yet to develop a fear of them.
Interestingly, even a stationary prop can generate fear in local Bernoullis. As the aircraft is parked and chocked it can't be drawn forward by the departing Bernoullis. This leads to a localised thinning of the air around the aircraft. The effects of this rarefied atmosphere can be seen to be best effect on, say, an early morning at Akrotiri. The crew may appear unsteady on their feet or drowsy and some of them be lying on the pan, under the wing, apparently unconscious. The younger, more inexperienced co-pilots often suffer the worst from this, what is basically a form of altitute sickness, and may often be seen vomiting on the nosewheel.
Champagne anyone...?
FEBA
Absolutely nothing. It was addressed to noprobs and the references he made in his post.
That said, surely this has to be first?? Somebody actually querying the relevance of a post to a thread title? Surely the idea of this place is to get away from the opening subject in as few moves as possible; or am I missing the point?
Now get back in your ditch.
Absolutely nothing. It was addressed to noprobs and the references he made in his post.
That said, surely this has to be first?? Somebody actually querying the relevance of a post to a thread title? Surely the idea of this place is to get away from the opening subject in as few moves as possible; or am I missing the point?
Now get back in your ditch.
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FEBA - Shhhushhhhhh! I'm learning things here. This is good stuff. Tell me - is it only the Aircrew that know about this stuff, or do the Ginger Beers know it too? Or was it classified? I can imagine that enemy forces would wish to control these Bernoulli thingys. Can they be controlled in any other way? It would make a very powerful anti aircraft weapon - perhaps firing extra Bernoullis in the path of aircraft?
Or am I thinking too much.
Or am I thinking too much.
Nozzles
Having considered your question I have concluded that it is a very good one
A very small amount of thought brings me to this conclusion.
Going supersonic means travelling faster than the sound you are making.
Therefore if you are not travelling with respect to the earth, you can't leave your noise behind, so no matter your altitude you will never go supersonic
Especially in those things
Having considered your question I have concluded that it is a very good one
A very small amount of thought brings me to this conclusion.
Going supersonic means travelling faster than the sound you are making.
Therefore if you are not travelling with respect to the earth, you can't leave your noise behind, so no matter your altitude you will never go supersonic
Especially in those things
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Nozzels
If I do a vertical take-off and do a perfect level attitude hover, how come I don't end up going round the World once every 24 hours?
Mmm. . . because you would be, essentially, in a very lo geo-synchronous orbit.
Anyway, you're already doing 19 miles per second just standing still!
If I do a vertical take-off and do a perfect level attitude hover, how come I don't end up going round the World once every 24 hours?
Mmm. . . because you would be, essentially, in a very lo geo-synchronous orbit.
Anyway, you're already doing 19 miles per second just standing still!
Err, nope. Can't be geosynchronous at anything other than in an equatorial orbit at an altitude of 36000 km. At that height gravitational and centripetal forces are in balance when the vehicle velocity is exactly equal to the earth's rotational rate.
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Quite! But why spoil it with facts? The grav and centrip forces you mention would obviously be equated by the thrust he would be producing. 
Anyway, Noz didn't say where he was doing it or how high he was a'hovering.
Anyway, Noz didn't say where he was doing it or how high he was a'hovering.
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Insty and beeayeate,
You guys are scaring me. I'm getting the horrible feeling that you thought my questions were serious. Here's another one that doesn't need to be answered:
If the space shuttle is doing 19 miles per second in space where sound can't travel, is it going supersonic?????
You guys are scaring me. I'm getting the horrible feeling that you thought my questions were serious. Here's another one that doesn't need to be answered:
If the space shuttle is doing 19 miles per second in space where sound can't travel, is it going supersonic?????
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Nozzles
For your information this thread is a serious one if it wasn't you wouldn't find contributers like Beagle or Stop Start posting on it, would you?
Hyper,super,trans sonic problems are not ones that we would normally associate with SHar pilots, any M number with a decimal point in front of it is more appropriate for you guys, that and a book of nostalgia.
Stop Start
Thank you for the helpful advice regarding my ditch. I read yesterday in the Sunday Times that Lord Hoon of Chilwell has withdrawn all ditches from service as part of his military cut back campaign. Troops will not be put at risk by this cut back as they will be able to make ample use of naturally occuring geological features such as casms rifts etc etc. Getting back to the navigational point of this thread, has anyone tried to get out of Rouen on the road to Dieppe recently?
Beagle
I'm looking on my keyboard to see how close D is to K
For your information this thread is a serious one if it wasn't you wouldn't find contributers like Beagle or Stop Start posting on it, would you?
Hyper,super,trans sonic problems are not ones that we would normally associate with SHar pilots, any M number with a decimal point in front of it is more appropriate for you guys, that and a book of nostalgia.
Stop Start
Thank you for the helpful advice regarding my ditch. I read yesterday in the Sunday Times that Lord Hoon of Chilwell has withdrawn all ditches from service as part of his military cut back campaign. Troops will not be put at risk by this cut back as they will be able to make ample use of naturally occuring geological features such as casms rifts etc etc. Getting back to the navigational point of this thread, has anyone tried to get out of Rouen on the road to Dieppe recently?
Beagle
Transport wander!