飛機升降問題

講得岩....好似kai tak o個度咁.......

d flaps 同 engines 真係好似就黎撞落去咁 = =""

因為飛機
起飛後要好大ge引擎弓率 機輪 你都知道飛機機輪 十分大如果唔收起機輪
飛機use油會多同埋飛機可能機輪墥都野so一定要

加大機體體積: 機輪會令飛機阻力增加, 引致速度減慢

Main Reason is the gears will destroy/adversely affect the streamline of the plane, inducing drag and wasting fuel consequently.

Please note there ARE plane with wheels/gears throughout the flight, e.g. Cessna.

The *height* of the gear/wheels is only ~2-3m, the assistance in avoiding clashing sth is very minimal. Also, there is no heating/air con in the places where the gears are stored, therefore they will experience the ambient temperature. The humidity at high altitude is around 15% (see how dry in the cabin?), so it*s not correct to claim the environment *humid*

2006-10-14 17:18:42 補充：
According to Aviation (Navigation) Ordinance of HK, a min altitude of 1500 feet is stipulated about building in flying, therefore 碰到地上建築物 is not possible.And, the gears are moving in the same speed with the plane, i.e. there is no relative movement, there shouldn*t be damage of releaving it.

2006-10-15 21:54:40 補充：
1. Cessna is 飛機 and it's a civil airliner too.2. Kai Tak airport is NOT the reason for retracting the gears. But the breaking of streamline. Otherwise, there can be airports that do not require retraction of the gears. See how *flat* Denver airport is?

2006-10-15 22:01:47 補充：
3. The gears in Cessna is protruding, then it's protruding. 唔怕撞 is not the reason, but the extra fuel required is offset by that required for the retractable gears. On the other hand, the gears in *heavy* can also be designed 唔怕撞.

唔收既會減慢左飛行速度,都有有機會碰到建築物
而且上到天咁高,好凍,又潮濕,好易結冰,有機會受損或折斷.

我們常稱飛機為「鐵鳥」，其實有鐵的部份還不到百分之一。一架這般巨大﹑笨重的飛機，如果以純鐵製造，肯定飛不起來。有機會到「機肚」部份，可以發現大部份都是薄塑膠。曾經有家航空公司的飛機，在收機輪時不小心撞到「機肚」，仍能支撐十多個小時航程來到香港，真是幸運。

因為方便些,而且若機輪沒有收起,會影響飛行,可能會碰到其他物體,造成意外