Why can't planes land in the fog, given that they can land in the dark?

Answer 1

Planes CAN land in fog, I've done it many, many times myself and have been a passenger on many, many flights that have done it as well. The presence of fog in no way implies zero visibility, and in fact, fog is not even an issue for a proficient instrument rated pilot in an aircraft equipped with an ILS receiver.

However, fog sometimes does limit the visibility to zero. Unless the aircraft and crew are certified for it, a plane can't land with zero visibility because you can't see the runway or runway lights.

Answer 2

Visibility. Depending on the technology onboard the plane and at the airport, regulations prevent a plane from taking off or landing at an airport that has a fog landing system if visibility is less that 600 feet. Some planes with high tech equipment are permitted to take off and land with 300 feet visbility.

The problem isn't just related to getting the plane into the air or onto the ground, the plane also needs to safely negotiate the taxiways and the airport itself.

Answer 3

Infrared technology may soon make fog nearly obsolete on landings. But everyone else above is correct. The remedy for darkness is as simple as turning on the lights, but the remedy for fog is a very expensive system known as a Category 3 ILS which requires extremely accurate equipment to be installed on the ground and in the aircraft as well as expensive training of the flight crew that must land the aircraft under these conditions.

Answer 4

They can if the runway is equipped for Cat 3 landings and the aircraft is fitted with auto land systems. For safety's sake though, the captain has to call a go around if he can't see the runway at decision height (50 ft).
It is not the landing that's the problem, but taxying around the airport looking for a jetway in thick fog and surrounded by very expensive aluminium.

Answer 5

You have to be able to see the runway in order to land.

This isn't a problem in the dark as the runway is lighted and the aircraft has landing lights to further illuminate the path.

However in fog you simply can't see the runway at all so therefore can't land safely.

Answer 6

Fog consists of tiny droplets of water vapor suspended in the air (in other words, a cloud), hanging near the ground. With the presence of fogs the visibility will be “zero-zero”—nothing but white ahead and above.
Whereas in the dark a tiny spark that can be seen can guide through the landing.

Answer 7

You can see runway lights in the dark, but not through fog.

Answer 8

It's a safety thing. Not just because you can't see the lights, although that is part of it. Modern aircraft avionics allow aircraft to land themselves in all weathers. But, just in case there is a computer drama the pilot would need to take over. So, if he/she can't see the lights then it would be a real drama.

Answer 9

in the fog you cant see the landing lights

Answer 10

Let's see, in the dark it is still possible to see the runway lights. When it is foggy I imagine it would be difficult if not close to impossible to see the lights.
I have never flown but personal experience from driving in the dark as well as foggy conditions helped me come to this conclusion. I could be wrong tho.