FSAirlines

Posted: **Tue Jan 08, 2008 3:23 pm**

I'm curious and just made some calculations of other necessary aspect - approach speed.
As more aircraft heavy is, as higher speed it has to maintain just to keep itself in the air.
So, I've presumed that I'll have land immediately after takeoff with fully loaded B747 and full tanks.
Calculated approach speed should be at least 180 kts with flaps dirty (dirty - pilots terminlogy fully extended), but 180 is a MAXIMUM speed for flaps dirty.
So I'll damage flaps or just will stall.
There simple rules of aerodinamic wich we should care about!

Posted: **Tue Jan 08, 2008 6:29 pm**

Myrm wrote:
Kimis wrote:..By the way, real A388 would be crashed during landing with such amount of fuel onboard. You should care about maximum landing weight.
That does not make sense to me! Imagine the scenario;

A B747-400 takes off from Kansas City, in the heart of the USA, for a long range flight. It's fuel tanks are full. As soon as it takes off it develops a serious fault, and needs to land again ASAP. Are you telling me that it would not be able to land due to being too heavy because of its full fuel tanks? It can't dump fuel because it's over land (I am lead to believe that planes can only dump fuel over large stretches of water, such as the ocean - though I must admit that I could be totally wrong. Perhaps the fuel can be dumped over land because it will evaporate before it hits the ground?) So the plane has to fly for several hours in order to either burn off the fuel, or get over the sea in order to dump fuel, and then return.

If a plane can take off with a full load, it must be able to land with a full load, surely!

Or am I totally out on this one?

With data directly from the boeing website, the B747-400 has a maximum takeoff weight of 396,894kg but a maximum landing weight of 285,764kg so assuming it took off from KC with a full load and had to return ASAP it would have to use or dump 111,130kg of fuel before landing.

FSAirlines

am holding off on this flight