Aircraft are subject to two types of airspeed restrictions set by the manufacture for safety reasons, these limits vary with altitude. The first limit is at lower altitude and is called Vmo-Maximum operating speed. This is a limit in KIAS that's normally around 320-360 KIAS and effective up to Flight Level(FL) 280-290(28,000-29,000 ft.). Above this altitude, the limiting speed is Mmo-Max. operating speed(Mach) and is expressed in percent of the speed of sound(the speed of sound is dependent on temperature) or Mach. This is normally around Mach .82-.88 depending on the aircraft. These speeds are listed in the aircraft documentation in FS.
The temperature, as an aircraft climbs, normally decreases. Mach .78 is faster at FL200 than at FL 350 because of the temperature difference. Normally aircraft have to be above FL 280 to achieve stated cruise Mach values.
Fuel- Large aircraft almost never take off with full fuel. Fuel load is based on the distance of the flight, 45 min reserve and any other fuel required to reach an alternate airport(if required). Full fuel would restrict the number of passengers and bags. Sometimes aircraft have to restrict the fuel load on a short flight because they will arrive at the destination with too much fuel(above Maximum Landing Weight).
ILS-The ILS is the normal aid for a large aircraft at a large airport in poor weather. During good weather, if available, pilots back up a visual approach with the ILS or other approach aids. Some runways are not equipped with an ILS and pilots are fully capable of landing a 747 on a runway using nothing more than their eyes.
I hope this in formation helps. 🙂
Last edited by CRJCapt on Fri Feb 02, 2007 12:31 pm, edited 2 times in total