The freedoms of the air
The freedoms of the air are a set of rights signed between countries, which grants the right to overfly an airspace and/or to land in those countries (bilateral treaties). There are 9 different freedoms, depending on the kind of flight. All these rules were defined in 1944 during the International Civil Aviation Convention in Chicago.
The right or privilege, in respect of scheduled international air services,…
1st.- …granted by one State to another State or States to fly across its territory without landing.
2nd.- …granted by one State to another State or States to land in its territory for non-traffic purposes
3rd.- …granted by one State to another State to put down, in the territory of the first State, traffic coming from the home State of the carrier
4th.- …granted by one State to another State to take on, in the territory of the first State, traffic destined for the home State of the carrier
5th.- …granted by one State to another State to put down and to take on, in the territory of the first State, traffic coming from or destined to a third State
6th.- …via the home State of the carrier, traffic moving between two other States
7th.- …granted by one State to another State, of transporting traffic between the territory of the granting State and any third State with no requirement to include on such operation any point in the territory of the recipient State
8th.- …of transporting cabotage traffic between two points in the territory of the granting State on a service which originates or terminates in the home country of the foreign carrier or (in connection with the so-called Seventh Freedom of the Air) outside the territory of the granting State (consecutive cabotage)
9th.- …of transporting cabotage traffic of the granting State on a service performed entirely within the territory of the granting State (stand alone cabotage)
Freedoms of the air
ETOPS: Unlimited Trustworthiness
The ETOPS (Extended-range Twin-engine Operational Performance Standards) defines the twin-engine aircrafts requirements to operate flights where the nearest enroute alternative airfield is further than 60 minutes.
At the beginning of commercial aviation, because of the lack of regulations concerning alternative airfields further than 60 minutes, the air carriers started putting pressure on Aviation Administrations to be modified, in order to be able to operate transatlantic routes with twin-engine. Because of that, ICAO and the FAA drawn up a new reguation that allowed to operate those routes.
Nowadays, there are several ETOPS ratings depending on some parameters. These parameters are including the engines and systems’ reliability, crew training and ratings, manteinance and so on.
Author Andrés Meneses
These are the different ETOPS ratings issued these days by Aeronautical Authorities:
- ETOPS-75
- ETOPS-90
- ETOPS-120/138 (138 minuts is a 15% plus 120 minuts, in order to cover a little part of the Atlantic Ocean, not covered with ETOPS-120)
- ETOPS-180/207
An ETOPS rating is gradual. That means if you want to reach ETOPS-120 rating, first of all the aircraft must have reached the ETOPS-75 rating (with 200 sectors with 98% relieability), then the ETOPS-90 rating (with 300 sectors with 98% reliability), and finally the ETOPS-120. For example, in order to achieve ETOPS-120 rating, the airplane must prove less than 0.05 per mil in-flight shut-down. That means, flying 20.000 flights there’s only one in-flight shut-down (obviously, an airplane does not achieve 20.000 routes in its life).
There’s a tremendous application called Great Circle Mapper where you can compute each ETOPS rating maximum range around the earth.