103 votes

Why are Gatwick's runways too close together?

Historically, Gatwick had only one runway (08R/26L) with a taxiway to the north, but this obviously would cause problems if that runway was out of use for any reason - emergency, scheduled maintenance,...
90 votes

Why don't short runways use ramps for takeoff?

V1. There are other valid reasons, as have been listed - cost, bidirectional runway use, etc. These would still not completely disqualify ramps, just limit them to very special circumstances. But the ...
  • 17.9k
82 votes

Why do control towers have tilted glass panels?

I'm pretty sure that has to do with reflections especially at night. If you have ever stood between two mirriors you will understand the infinity mirror. Light bounces back and forwards between the ...
  • 4,846
73 votes

Why are Oscar, India, and X-Ray (O, I, and X) not used as taxiway identifiers?

Because those symbols are easily confused with the number 0, the number 1 and the symbol for a closed runway/taxiway (✕) respectively. (1) Numbers by themselves, and the letters "I" ...
71 votes

Why do airports have directional runways instead of a large area to operate in any direction?

The typical World War II "A" runway shape solves this issue, without covering a huge amount of area with concrete, etc. Even so, that configuration has fallen out of use in modern airports. ...
  • 8,870
68 votes

Why can't some airports handle heavy aircraft while others do it easily (same runway length)?

There are a few possible reasons Bournemouth (EGHH) can support a Boeing 787 but Kherson (UKOH) can't. Runway length is definitely not the issue. The runway at EGHH is 2271 metres long, the one at ...
65 votes

Why do airliners park with the nose facing the terminal?

To park a passenger plane with its tail towards the terminal has several disadvantages: it would require a pushback tractor (plus personnel) to do that. Thrust reversers in general are not meant for ...
  • 24.8k
63 votes

Why do airports in the UK have so few runways?

There are perhaps 101 non aviation-related reasons why the UK does not have larger airports, such as space consideration (we're only a small island!), politics (NIMBY!), civil engineering (Airports ...
  • 27.1k
59 votes

How to build a 2 mile long runway on a 1 mile square island?

Anyone who has ever flown at Zar (EPZR) in Poland knows how much a runway slope can reduce the needed field length. For aircraft which need a 2 miles long level runway, a 1 mile long one with a 15% ...
54 votes

Is there any combination of two airports that are connected via taxiways?

There are numerous joint use (commercial/military) airports with separate terminals/ramp areas. There aren't many where there are two connected fields. The only one I'm aware of is Naval Air Station ...
  • 18.4k
50 votes

Why don't short runways use ramps for takeoff?

Because then you can only land in one direction. What do you do if the wind blows exactly along the runway so that departing and landing planes have only tailwind then? You would waste a precious ...
  • 32k
48 votes

What is the purpose of a walled area in the vicinity of Heathrow Airport?

It allows them to do a run-up test of the engines without blowing debris at other parked aircraft, people, or things on the ground. [Credit to Ralph J] The walls have a structure that allows the ...
  • 35.7k
44 votes

Why do farmers register their fields as airports?

Just spoke to the farmer that owns Graham Farms Airport (SN72), a grass strip in a cornfield near the sprawling metropolis of Harris, Kansas. Here it is on the sectional: And Google Earth: ...
  • 27.9k
43 votes

Is there any combination of two airports that are connected via taxiways?

I think Chitose and New Chitose on Japan's Hokkaido island fit the criteria. One is an air base (Chitose) with ICAO code RJCJ, while the other is the island's ...
42 votes

Why do airports remove/realign runways?

In some cases the prevailing winds change and certain runways fall out of use. Since airports tend to be land limited they may wish to use the land for hangars or other facilities so the runways are ...
  • 97.6k
37 votes

Why do farmers register their fields as airports?

Private airfields are not at all uncommon in the U.S., especially the rural parts (which is most of the U.S.) These are probably for crop dusting or because the owner also happens to be a private ...
  • 19.1k
35 votes

What's the reason for this frog finger shaped parking lots at Köln/Bonn airport (CGN)?

@Simon is right. The 'parking lots' are actually dispersal areas in the (previous) military airfield at that place. The Cologne Bonn Airport started out as an airfield for Luftwaffe in 1938 in what ...
  • 99.2k
35 votes

Is there any technical reason that prevents installation of a jet blast deflector at Princess Juliana airport?

An immobile jet blast deflector could not be built far enough away from the runway end to be safely clear of the landing path. Large airplanes like 747s must touch down pretty close to the near end of ...
  • 51.7k
34 votes

Is there any combination of two airports that are connected via taxiways?

The airports in Berlin share runways. Strictly speaking, one of them (BER) isn't really operational... But it will be. Soon. For sure... Hey, look over there: a monkey with two heads!! google maps
  • 743
34 votes

Do any airports have runways or taxiways that cross active rail lines at grade?

There is at least one: In Gisborne, New Zealand, there is a freight rail line which crosses the south end of runway 14/32 at Gisborne Airport (GIS). It appears to still be an active line for freight (...
  • 1,447
33 votes

Why do airports in the UK have so few runways?

It's ALL about land use. Look at Mirabel, Denver's new airport, or Dulles (at the time it was built). They basically razed some farmland. America had the opportunity to do a whole lot of that. ...
32 votes

Why was the second runway at Sea-Tac Airport built so close to the first?

TL;DR/Abstract - Political, financial, and social expedience are often the dominant forces in the development of infrastructure projects - Sea-Tac is no exception. The history of Sea-Tac is messy, as ...
31 votes

Why are most helipads in São Paulo blue coated and identified by a "P"?

According to the Rules for Heliports in Sao Paulo, the P means that it is private heliport. H for public Heliports, M is for military. Hospitals use the letter H on a red cross, also when they are ...
  • 76.5k
30 votes

How do passengers board the planes on this airport?

They are specially designed apron jet bridges. It looks like the normal gates but required to transfer passenger by bus. A model shows how it runs (credit) :
  • 5,268
30 votes

Why do airports remove/realign runways?

Three runways (or pairs) 60 degrees apart was very common. Where land was limited, two runways (or two pairs) at 90 degrees was almost as good. These generic designs could be built very quickly almost ...
  • 27.3k
30 votes

Why do airports have directional runways instead of a large area to operate in any direction?

We have runways for the same reasons that we have roads: All traffic needs to move in the same direction, in visually easily identifiable lanes. Channeling the traffic improves safety and efficiency. ...
  • 60.3k
29 votes

Why aren't airports built identically (like aircraft)?

1. Terrain and land use Several new airports are build on landfill island or coast next to mountains, their shape is influenced by the terrain and their size. Hong Kong International Airport runways ...
  • 5,268

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