It helps them to get air under the wings its a much better take off
In general and not specifically Heathrow aircraft takeoff into the wind, this helps reduce the four flight problems of weight, drag, thrust and lift. I hope this answer helped
runway
coze it needs more speed to take off
Special wheels and axels called landing gear.
Mostly they do, not always. It is more efficient to take off into wind.
Yes a head wind and flaps set to mid for wing configuration
No. An aircraft takes off and lands into the wind. (Or as close as possible to directly into the wind).
If it can be helped always land and take off into the wind (wind in your face)
If conditions (airport layout and traffic conditions) allow aircraft take off and land against the wind (headwind). This way the aircraft can take off or approach the runway at a lower ground speed.
They have streamlined bodies so that they can cut through the wind and air
Most Aeroplanes can take off with full fuel tanks, however it is common practice for planes to take off with enough fuel to get them safely to the destination, excess fuel adds weight and it's uneconomic to carry it.
Because you want full 360 degree vision available.