ETOPS: Unlimited Trustworthiness

ETOPS: Unlimited Trustworthiness

by Aviationer || Category: Airlines, Regulations

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.

Bookmark It!

1 Comment

1 Comment so far

  1. Crossing the Skies » North Atlantic Routes: I eat beef, you eat fish November 7th, 2008 10:46 pm

    […] aircrafts operating these flights (usually big ones) must have the ETOPS rating, explained in other post. That is because, the nearest alternative airport when flying above the atlantic is 180 minutes […]

Leave a comment

name (required)

email ( non sarà visibile ) (required)

sito web


Search for:



  • Aerodynamics
  • Airlines
  • Airplanes
  • Airports
  • Amazing stuff
  • Events
  • Off Topic
  • Regulations
  • Uncategorized


747ACAPaccidentacrobaticsaerolineaaeronauticaeronaveairbusaircaftaircraftairlineAirlinesairplaneAirplanesairportamazingATCatlanticaviationavionBoeingcharacteristicscrossingdesignengineETOPSextendedextended rangeflightflyFuelheavyJARjettisonmotorNATOPSracerangeroutesrunwayshowtrackstwinWelcome



Crossing the Skies © powered by WordPress || Theme by Mukkamu

Leave a Comment