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Old Nov 16, 05, 3:48 pm
Join Date: Dec 2000
Location: PHL, NYC
Posts: 8,591
The range is only affected because the weight has to be altered in cases where the runway isn't long enough to achieve take off speed during hot days. If that weight is not reduced in the form of pax or cargo, then it has to be fuel, which translates to range reduction.

The only real problem with hot airports(and high, like DEN) is actual take off or landing performance.

Heat simply raises the density altitude, which makes the air thinner than standard, which means the aircraft must use up more runway to gain the same indicated airspeed before reaching liftoff speed. A 100 degree day in Denver, already at 5000 feet above sea level, makes it the equivalent of being at 9000 feet at normal conditions. This is why you are, in fact, moving along the ground much faster when taking off/landing at these airports. The plane has to move faster to achieve the necessary indicated airspeed since it's less dense than at sea level (like PHL, JFK, BWI, etc.)

Las Vegas' longest runway is 14,510 feet long, which should suffice for most heavily loaded aircraft on hot days. PHX, by comparison, has a max length of 11,489 feet, which is more in line with most other major airline airports. That would be a constraint on long haul departures (fully loaded) on hot days.

Denver Intl, built brand new in the middle of nowhere 13 years ago, was able to incorporate a 16,000 foot runway for those days where the temps are high.

Sorry for the digression, but I eat this stuff up. Density Altitude has gotten a lot of general aviation pilots killed when flying in/out of high/hot airports because they were used to sea level airports and denser air.

All that being said, a fully loaded A330-200 might be pushing its limits in PHX on hot days.
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