Why do we Lose Airspeed in a Turn and What Causes This?
Fly Conventional Gear
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What I was taking issue with was that he seemed to be saying that the aircraft has a certain amount of inertia (taken to mean momentum) because of its ground speed and that the momentum of the aircraft related to its groundspeed. (Which sounded a bit like what Mike Ox was saying right at the start.)
As I said, Momentum is proportional to velocity which is relative to the observer. Yes, an aircraft with more ground-speed has more momentum, because to have more ground-speed it must also have more airspeed. The figures work whatever the frame of reference. If you were in an aircraft going the other way, or in a balloon travelling at the speed of the local wind, the speed changes you would observe in the aircraft encountering windshear would be the same relative to you.Groundspeed is just a convienient reference, no truer than any other.
If you look at an earlier post of mine, you'll see that I tried to explain that the confusion here lies with the difference between speed and velocity. The downwind turn brigade are of the opinion that an aircraft turning at a constant gound speed has a constant velocity. It doesn't. Velocity is a vector meaning it has magnitude and direction. Change direction and you have changed velocity, which is defined as acceleration.
They think that because an aircraft going from up-wind to down-wind changes ground-speed it has to accelerate more in the down-wind case. It doesn't. In both case the acceleration is the same, cause by imparting the same force and with the same result.
Think of it this way- going from 100 kts west to 100 kts east is an acceleration of 200 kts towards the east. Going from 50 kts west (with a 50 kt wind) to 150kts east is ALSO a 200 kt acceleration to the east, so it actually does work reference the ground (or any other frame of reference.)
As a pilot, however, the most convienient frame of reference is the air around you, and that is the only one that the aircraft feels.
If you look at an earlier post of mine, you'll see that I tried to explain that the confusion here lies with the difference between speed and velocity. The downwind turn brigade are of the opinion that an aircraft turning at a constant gound speed has a constant velocity. It doesn't. Velocity is a vector meaning it has magnitude and direction. Change direction and you have changed velocity, which is defined as acceleration.
They think that because an aircraft going from up-wind to down-wind changes ground-speed it has to accelerate more in the down-wind case. It doesn't. In both case the acceleration is the same, cause by imparting the same force and with the same result.
Think of it this way- going from 100 kts west to 100 kts east is an acceleration of 200 kts towards the east. Going from 50 kts west (with a 50 kt wind) to 150kts east is ALSO a 200 kt acceleration to the east, so it actually does work reference the ground (or any other frame of reference.)
As a pilot, however, the most convienient frame of reference is the air around you, and that is the only one that the aircraft feels.
Fly Conventional Gear
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So big planes are more vunerable to windshear because when they loose airspeed they don't regain it as quickly because of their momentum (mass x airspeed)?
Fly Conventional Gear
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Thanks for clearing that one up 
Before I learnt to fly I was always under the misconception (probably like a lot of people) that heavy jets were somehow less affected by the wind and associated atmospheric phenomena than small ones.
Before I learnt to fly I was always under the misconception (probably like a lot of people) that heavy jets were somehow less affected by the wind and associated atmospheric phenomena than small ones.
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Lose Airspeed?
See like dude when you turn like some of the little lift guys fall off the wing and get killed like so you gotta pull back on the stick (a yoke is what transport guys have, pilot guys have a stick) to kinda glue the little buggers on to the wing so you don't leave little dead lift guys all over the place. When you pull back on the stick these lift guys get much bigger (which keeps them on the wing) but they decide to have a party and invite all their drag mates to come along 'cos they think they're so tough. This is a real bummer 'cos the drag guys mess the whole thing up by burning energy which slows ya down.
See it's that simple!
or I guess you could talk Bernoulli, Coefficient of Lift Vs Coefficient of Drag etc etc but I like the first answer better.
See it's that simple!
or I guess you could talk Bernoulli, Coefficient of Lift Vs Coefficient of Drag etc etc but I like the first answer better.
You are in for a treat as I will contribute later, having clarified my thought processes in happy hour,
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So, if stones sink in a pond but gravy doesn't........ but wood floats, and 'She Floats', She's made out of wood 'Right?'........ So She's a Witch!!!! ...... Burn Her! ... etc etc etc
Advo
PS: This is the funniest thread I've read in ages. Thanks.
Advo
PS: This is the funniest thread I've read in ages. Thanks.
