9

To be clear this is not a question on doing anything illegal. The question is about realms of control, and when you're "visiting" the territory of a country.

According to the UN's rules, territorial waters extend 12 nautical miles outside of the land. So to travel to country X, entering into those areas would put you under their territory.

What I'm wondering is whether a similar convention exists for altitude above ground/sea-level. I assume there's some limit, or the ISS would arguably be crossing countries' territories all the time...

Improve this question
7
  • 1
    When you fly you are traveling above the control of many countries...
    – Nean Der Thal
    Commented Aug 19, 2013 at 6:41
  • But they control the airspace, and can order you down...
    – Mark Mayo
    Commented Aug 19, 2013 at 6:46
  • 1
    There are certainly flights which go around entire countries.
    – hippietrail
    Commented Aug 19, 2013 at 7:43
  • 4
    Stratospheric balloon flights, at 30 km+, need permission from the countries they fly above.
    – gerrit
    Commented Aug 19, 2013 at 9:12
  • 3
    I always think about this when I see an airplane go over my farm. I own that piece of land and the air and the skies above. Those airline fellas need to pay me to fly over my land ! Or atleast give a few free tickets :)
    – happybuddha
    Commented Aug 19, 2013 at 15:51

4 Answers 4

Reset to default
13

Not without getting into what's technically defined as "outer space". From Wikipedia:

There is no international agreement on the vertical extent of sovereign airspace (the boundary between outer space—which is not subject to national jurisdiction—and national airspace), with suggestions ranging from about 30 km (19 mi) (the extent of the highest aircraft and balloons) to about 160 km (99 mi) (the lowest extent of short-term stable orbits).

Essentially, if it's considered airspace, rather than outer space, you're in the jurisdiction of the country you're over. If you've got a craft that can comfortably fly in "outer space", then enjoy your jurisdiction-less travel.

Improve this answer
2
  • So an airline passenger could be prosecuted if they do something illegal under the laws of the country which they are overflying at that moment, if they later visit that country or anywhere that has an extradition treaty with it?
    – bdsl
    Commented Jan 7, 2021 at 20:17
  • I see that the question has been asked at aviation.stackexchange.com/questions/2358/… and apparently the answer is yes.
    – bdsl
    Commented Jan 7, 2021 at 20:20
10

A convention sort of exists, in that countries recognize there's a limit, but they don't exactly agree on what the limit is. In any case, though the average consumer isn't getting that high up (at least for now).

Wikipedia says, on the subject of how high sovereignty extends,

There is no international agreement on the vertical extent of sovereign airspace (the boundary between outer space—which is not subject to national jurisdiction—and national airspace), with suggestions ranging from about 30 km (19 mi) (the extent of the highest aircraft and balloons) to about 160 km (99 mi) (the lowest extent of short-term stable orbits).

19 mi is roughly twice the largest absolute ceiling of commercial and business aircraft; you might be able to get up there with a military jet, but well, if you're flying military, the rules are probably bendable anyway.

Improve this answer
4

I would like to add to the other answers that once you pass the 30km (19 mi) height (which is possible with a stratospheric balloon) you are effectively outside of the actual control of a country. There is no weapon or force available in this height which can reach you. Most of the available missile systems reaches up to 25 km and even the SR-71 Blackbird cannot fly higher than 26 km horizontally. The US and Russia may have anti-satellite weapons, but any other country is pretty helpless against people flying in this height.

Improve this answer
4
  • 3
    "higher than 26 km horizontally"? Surely one of these words is not the right word? (-:
    – hippietrail
    Commented Aug 31, 2013 at 3:35
  • 1
    @hippietrail Just guessing but maybe “horizontally” means “in sustained horizontal flight”. Some maneuvers can briefly bring military aircrafts higher.
    – Relaxed
    Commented Jan 21, 2015 at 13:27
  • Ah so the Blackbird can hit 26km elevation but cannot fly horizontally at same?
    – hippietrail
    Commented Jan 21, 2015 at 13:36
  • @hippietrail Exactly as Relaxed said. While you as human are bound to the gravity of earth and cannot elevate yourself permanently on a long plain area, you can jump up and therefore get temporarily higher. You can use your high velocity with a plane to climb up, but your plane will slow down steadily until it comes to a standstill and comes down again (in reality, in such altitudes it will lose its lift long before a standstill is reached).
    – Thorsten S.
    Commented Jan 24, 2015 at 1:17
4

While there is no international legal agreement as to a specific altitude at which space begins, international law defines the lower boundary of space as the lowest perigee attainable by an orbiting space vehicle. The term "orbiting" implies unpowered flight, which given atmospheric drag means an altitude of around 150 kilometres.

Alternatively, the Karman line at 100 kilometres altitude is accepted by the Fédération Aéronautique Internationale as the boundary between airspace and outer space. It is at this altitude that the atmosphere becomes too thin to support aeronautical flight (using wings to generate lift) as the speed required to generate lift is greater than the speed of a ballistic trajectory (rocket flight).

Improve this answer

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .