Oops, sorry didn't see pages 2 & 3.

"Nothing to do with the jet stream--that affects the weather." Jet steams do affect the weather but have a significant influence on on aircraft routing and flight times. Flights across the Atlantic take advantage of it from USA to UK and it reduces flight times. Going the other way then flights have a headwind. See E-How.

This is an east-west influence and has little to do with a flight to Palma.

Woolwell

I was aware of that, but kept it brief as I assumed CurlyWhirly wasn't going the long way round!! (:-}}

FE

"The reason for this is to reduce stress on the pressurised section of the fusilage."

That's a myth. The fuselage of a modern passenger aircraft is built to withstand cabin pressure changes, and can easily handle the stresses involved

An airframe has a finite life. Every takeoff/landing cycle inflates the pressurised section like a balloon, only not as noticeable. Every time you distort metal, fatigue takes place, even though it may not be visible to the naked eye. In fact the science (I used to think of it as a black art when I was mending aircraft) of non destructive testing (NDT) is a highly specialised trade in itself. But I digress. Inflation/deflation of a balloon will eventually leave it ragged and floppy. You can increase the number of times you can blow up the balloon by not blowing it up as much. Also, the length of time it remains inflated does not significantly alter the life of the balloon. Hence a long haul aircraft suffers significanly less wear and tear than a short hop commuter. This was illustrated all too dramatically when a 747 went down I think somewhere in japan. The crash was shown to due to a failure of the rear pressure bulkhead (a dome like structure). The aircraft was subsequently shown to have an abnormally high takeoff/landing cycle.

WTM

(BTW CurlyWhirley, enjoy your holiday.)

WTM