Hello, Dudes!

 

What are the limitations which a commercial plane cross of a Country? I've no idea of that. At how much height a one country's plane can remain on a second country? Or it's not height problem? If it's not height problem then is it a specific zone problem? What actually it's? I don't know its basics. Please help me.

 

Regards,

 

AP,

From my understanding, the airspace above a country belongs to this country from the Earth's surface up, without upper border, although, according to wikipedia, it is usually limited to 100km altitude (approximately 300 000ft). If we're talking about civili aviation, according to the Chicago Convention on International Civil Aviation, every civilian plane may pass any country without prior permission, and it is allowed to land there under the premise that this landing is due to technical issues (e.g. emergency or refuel), i.e. no deboarding in whatever way. In short, if I understood correctly, fly-over rights are not necessary for any civilian plane, but you will need permission to land and deboard a plane legally at your destination airport!

However, there can be some exceptions. For example, if there are special events (e.g. visits of the President of the U.S., rocket launches etc.), no-fly zones can be created an inforced, but in this case NOTAMs will be released informing pilots about the details.

 

In justified cases, I also think that civilian airplanes may be forced to land by a country.

 

(For military aviation, these rules obviously do not apply. Every country has its air sovereignity, and any violations could in theory be punished, hence military fly-overs require the permission of the regarding countries.)

Its mean, suppose, if one country's plane is going over the second Country at 10,000ft, then there will not be violation of air-limits?

 

Suppose, if UK's plane is going at 10,000ft in US then this isn't violation of air limitations?

 

Another question, if this isn't violation then why maximum planes fly over a country at 31000 to 40000ft? Why they don't fly at 10000?

I'm talking about height. Means from Country's surface to sky. What is the minimum height of a plane on which a second country understand that first country's plane is doing violation of our air field?

 

 

Its mean, suppose, if one country's plane is going over the second Country at 10,000ft, then there will not be violation of air-limits?

If it's a civilian plane, that wouldn't be a violation (supposing that the plane was cleared to take-off, that is -_-)

 

 

 

Another question, if this isn't violation then why maximum planes fly over a country at 31000 to 40000ft? Why they don't fly at 10000?

The reason for flying at high altitudes is simply fuel efficiency: "Thinner" air (less particles) at FL350 than at 10000ft results in less friction (not sure whether this is the correct term here, though) results in lower fuel consumption. (On a sidenote, although that is most likely not the reason, that makes a greater space available for the planes).

 

 

 

What is the minimum height of a plane on which a second country understand that first country's plane is doing violation of our air field?

Again suposing it's a civilian plane with all the necessary ATC clearences, it would basically never violate an airspace according to the Chicago Convention on International Civil Aviation (unless the plane is in a published no-fly zone, as explained above).

From a legal point of view, a coutry's airspace reaches from the ground upwards, without a defined end, but without endangering persons or property, one can probably fly as low as he wants. Exceptions apply here as well, e.g. for noise abatement.

 

The reason for flying at high altitudes is simply fuel efficiency: "Thinner" air (less particles) at FL350 than at 10000ft results in less friction (not sure whether this is the correct term here, though) results in lower fuel consumption. (On a sidenote, although that is most likely not the reason, that makes a greater space available for the planes).

 

Lovely Answer. Thanks.

 

Last is that if a British Airway Passenger plane comes from Heathrow and goes over Pakistan at 10,000ft height and its destinations is Japan, then would there be not the violation of Pakistan's Air space?

 

Another example is that, same thing, if a passenger A380 of Dubai, Emirates goes over Heathrow (without landing in UK) and its destination is Chicago then would it not be the violation of British Airspace?

 

What about this news? What has happened?

 

http://www.thenews.com.pk/article-102414-PIA-plane-lands-at-Manchester-airport,-probe-continues

 

 

Regards,

 

Your Friend,

 

AP,

 

 

What about this news? What has happened?

From what I read in another article, and the one you're referring to agrees on that, the problem was that some passengers threatened to "blow the plane", which is why the crew alarmed the controllers. Then obviously the RAF sent some Europfighters to escort the plane to Stansted.

So technically that was not a violation of air-sovereignity, but a suspected terrorist attack. I think that from the crew's perspective it definitely was the right action, in order not to endanger passengers or people on the ground, such threats have to be taken seriously, especially after 9/11.

 

Regards,

Flo

Actually overflying of a another country is only allowed with prior permission. About 130 countries have signed the International Air Services Transit Agreement which means they automatically allow planes from other signatories to overfly their territory, but a couple of big countries (e.g. Russia and China) never signed, so you will need a separate treaty or permission. One of the ways Russia fought the EU emissions trading scheme was to threaten to ban overflights of Russian territory.

Countries are also allowed to restrict overflights to certain routes and to charge navigation fees to allow overflights. More information on wiki: http://en.wikipedia.org/wiki/Freedoms_of_the_air

 

The altitude of the overflight doesn't matter, although a country usually has rules about minimum altitudes in various areas which apply to all flights, whether they're overflying or staying within a country. A country controls all airspace above it's territory (and territorial waters possibly?) from the Earth's surface up to space (100 km up, by international definition). Of course flying higher is beneficial, as it makes you plane more fuel efficient.

 

The reason for flying at high altitudes is simply fuel efficiency: "Thinner" air (less particles) at FL350 than at 10000ft results in less friction (not sure whether this is the correct term here, though) results in lower fuel consumption. (On a sidenote, although that is most likely not the reason, that makes a greater space available for the planes).

The correct term is drag. Friction is one of the things that cause drag, but not the only thing.

 

 

but a couple of big countries (e.g. Russia and China) never signed, so you will need a separate treaty or permission.

Thanks, I thought that I was missing something, but I couldn't find the error.

 

 

 

The correct term is drag.

Once more, thanks. In German we use the same word (with some prefixes to differ, though) for all these phenomena, that's probably why I tend not to remember them correctly.

@FloG @japascoe: Thanks Guys! These are fascinating answers. Thanks to both. Specially, Flo! has done terrific jobs with writing more threads.