Is Plane lighter going west than going east?
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...and don't forget the increase in mass due to aircrafts velocity in the Earths gravitational field. However, the E=W+Mc2 sh*t first really kicks in at speeds appraocing 60% of lightspeed, so no great operational concern 
Concerning the particle / photon thread : would this mean that the aircraft would need to produce more lift during high altitude / high lattitude flight due to increased cosmic radiation level
And finally : Raising the cabin temperature would tend to expand the airframe, thus increasing form drag (and possibly friction drag due to expanding gaps in the airframe). So should complaints about low cabin temperature be answered by a curt: "You want to arrive on time, don't you, Sir"?
Now I cannot dream up any more variables affecting aircraft performance for the fly-f***ing department to consider - might as well go to sleep
Concerning the particle / photon thread : would this mean that the aircraft would need to produce more lift during high altitude / high lattitude flight due to increased cosmic radiation level
And finally : Raising the cabin temperature would tend to expand the airframe, thus increasing form drag (and possibly friction drag due to expanding gaps in the airframe). So should complaints about low cabin temperature be answered by a curt: "You want to arrive on time, don't you, Sir"?
Now I cannot dream up any more variables affecting aircraft performance for the fly-f***ing department to consider - might as well go to sleep
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Does this all mean that we need to recalculate and rebug landing weights when turning from downwind to final on an east/west runway ???
Strewth, it's getting very technical...
Strewth, it's getting very technical...
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Travelling east does reduce your effective weight, and after a long sequence of confusing mathematics it seems to cause a loaded 747 to effectivly weigh 99.7% of its actual weight. On the flights we do across the Pacific pond easterly from ozland to usland that equates to very roughly 1.2 tonnes of fuel, and that IS a lot of fish.
edited for typos.
[ 08 September 2001: Message edited by: Back Seat Driver ]
edited for typos.
[ 08 September 2001: Message edited by: Back Seat Driver ]
Avoid imitations
Join Date: Nov 2000
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Ivan,
The expansion drag increase of the airframe is somewhat nullified by the fact that warmer air is lighter, reducing the all up mass and therefore allowing a reduction in angle of attack. Additionally, passengers travelling from further west are generally warmer when they board the aircraft so the fuel used to heat the cabin is also reduced, so this needs to be allowed for.
This thread has made me realise after 25 years of professional flying that I was never cut out to be a pilot.
How on earth are we supposed to calculate our fuel load these days? What we actually need are some mathematicians to sit up front..
"Captain to F/O, you have control - of the calulator. Quick, work out how much nose up I need to stop this rate of descent - what do you mean the batteries are flat?
"
Excuse me while I nip out to fill up my car with petrol. Anyone give me guidance on how much to put in for the coming week?
The expansion drag increase of the airframe is somewhat nullified by the fact that warmer air is lighter, reducing the all up mass and therefore allowing a reduction in angle of attack. Additionally, passengers travelling from further west are generally warmer when they board the aircraft so the fuel used to heat the cabin is also reduced, so this needs to be allowed for.
This thread has made me realise after 25 years of professional flying that I was never cut out to be a pilot.
How on earth are we supposed to calculate our fuel load these days? What we actually need are some mathematicians to sit up front..
"Captain to F/O, you have control - of the calulator. Quick, work out how much nose up I need to stop this rate of descent - what do you mean the batteries are flat?
"Excuse me while I nip out to fill up my car with petrol. Anyone give me guidance on how much to put in for the coming week?
Thread Starter
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Let me repeat again, if it is not the wind then this would be a very very interesting result.
Have the wind effects been subtracted out? Is this what was meant by the same conditions?
And how does one do this? Does one have accurate enough readings of doppler radar reflections from flying dust showing wind velocity relative to the ground at various altitudes where the plane is flying etc..?
Is it possible to say that repeated trips indicating more fuel used going west to east the same distance could not be accounted for by some systematic wind effects given the 200kg difference in fuel for the same specific distance?
Have the wind effects been subtracted out? Is this what was meant by the same conditions?
And how does one do this? Does one have accurate enough readings of doppler radar reflections from flying dust showing wind velocity relative to the ground at various altitudes where the plane is flying etc..?
Is it possible to say that repeated trips indicating more fuel used going west to east the same distance could not be accounted for by some systematic wind effects given the 200kg difference in fuel for the same specific distance?
