As a passenger, you might see the word “ETOPS” (pronounced Ē-Tops) stenciled on airplanes. Occasionally, you’ll hear about it in the news. Follow a few AvGeeks on Twitter or Facebook and you’ll most definitely see this term used, joked about, and misused. What does ETOPS mean and why is it important?
[Author's note: Information in this article is based on United States air regulations. ETOPS rules and terminology may differ in other countries]
ETOPS: Acronym for Extended Operations. ETOPS is a set of rules that enhance safety when flying over areas of the world that have few airports that can be used in an emergency.
Suitable Diversion Airport (sometimes called an alternate): A preselected place to land in the event an airliner has a problem during a flight. A diversion airport must have appropriate facilities to handle the aircraft and meet minimum weather criteria.
The 60 Minute Rule
Airliners with two engines can fly most any route, as long as they stay within 60 minutes flying time of an airport that is adequate for landing in the event of an emergency. The 60 minute distance is calculated using the aircraft’s speed with one engine inoperative in still air (no wind). As an example, the 60 minute distance for the 767 I fly is about 430 miles.
North America and Europe have numerous airports that can handle airliners. When flying over these continents, it’s unusual to be farther than 60 minutes from a place to land in an emergency.
The 60-minute rule requires two-engine airliners to stay within 60 minutes of an airport. This flight is not allowed to fly a direct route between Gotham and Metropolis.
The same regulation that limits two-engine airplanes to the 60-minute rule allows passenger jets with more than two engines (like a 747 or A340) to venture as far as 180 minutes from an airport. 180 minutes gives these aircraft access to 95% of the earth’s surface. Aircraft with more than two engines are rewarded with a longer leash due to increased engine and systems redundancy.
More Than 60 Minutes in a Twin = ETOPS
What happens if we want to fly a two-engine aircraft, like a Boeing 777, out over the ocean? The 5 1/2 hour flight from Los Angeles to Hawaii takes us way beyond 60 minutes from an airport. For a two-engine aircraft to exceed the 60 minute rule, we need… more rules!
ETOPS to the rescue!
Over the past few decades, aircraft systems and engines have become amazingly reliable. Because of this reliability, ETOPS rules were created to allow two-engine airliners to fly beyond 60 minutes from an airport. The same regulations allow passenger aircraft with more than two engines (like the 747 and A380) to fly beyond 180 minutes from an airport.
There are different ETOPS ratings available. Typical two-engine ratings are ETOPS-120 (minutes) and ETOPS-180. The higher the rating, the more difficult and costly it is to receive and maintain approval.
Using ETOPS-120 authorization, this flight can use Riverdale and Metropolis as ETOPS emergency diversion airports to fly the direct route between Gotham and Metropolis.
120 minute ETOPS works well for many long flights, including most routes over the North Atlantic. If an airline wants to fly more remote routes, like the Pacific ocean, it needs approval for 180 minute ETOPS. Hawaii and Asia are just too far from the U.S. mainland for an ETOPS-120 rating.
Two-engine airliners need at least ETOPS-180 approval to fly from the U.S. to Hawaii or Asia.
Aircraft Type Approval is the first step of the two part ETOPS approval process. The aircraft model type must be approved for extended operations. To gain approval, manufacturers must include extra redundancy for key systems like electrical, hydraulics, fire suppression, and communications.
Based on the design of the plane and engines used, federal agencies (like the FAA or its European equivalent, EASA) will grant the aircraft model an ETOPS “type approval” that designates how many minutes it can safely operate with one engine inoperative. The Boeing 777 ETOPS models have a type approval of ETOPS-330. The Airbus A350XWB was granted ETOPS-370. These two aircraft are certified to fly over 5 hours from an emergency diversion airport - on one engine. Thousands of hours of engine performance and maintenance data are required before and airplane can acquire these impressive ratings.
Part 2. Operational Certification
Once the aircraft has ETOPS type approval, airlines must receive their own approval based on the routes they plan to fly. Aircraft certified for ETOPS have demanding maintenance requirements. Airlines must develop a special maintenance program for the aircraft they want certified. The higher the ETOPS rating, the more stringent the maintenance requirements. Frequent inspections for key aircraft systems with special attention to the engines are necessary. Airlines must also fly validation (test) flights on proposed ETOPS routes to demonstrate procedures to federal regulators.
Airlines often apply an ETOPS decal to certified aircraft as a reminder that the aircraft requires special attention. Photo: Southwest ETOPS 737 – By author.
ETOPS also requires special flight crew and dispatcher training, additional weather planning, special fuel quantity considerations, and enhanced communication capabilities (satellite communication is often used). A very important requirement for each ETOPS route flown is a passenger recovery plan.
Passenger recovery plan?
That sounds pretty ominous. No worries! The passenger recovery plan details how the airline will manage its passengers in the unlikely event of an emergency landing at an ETOPS diversion airport.
When an airline plans an ETOPS flight, they have to select suitable diversion airports to use in an emergency. Diversion airports must have the infrastructure necessary to handle passengers, often in remote areas of the planet. A little airstrip with one outhouse won’t work when flying over the North Atlantic in January. That’s why Halifax, Nova Scotia and Keflavik, Iceland are popular diversion choices for Atlantic routes. They can handle an extra 300 passengers in the event an A330 drops in with a problem. A recovery plan doesn’t have to promise everyone a room at the Ritz-Carlton, only that passengers will be reasonably comfortable and that basic physiological needs are met (safety, shelter, food, and bathroom facilities). The passenger recovery plan assures that passengers arrive at their final destination within 48 hours of the diversion.
ETOPS Navigation Charts
Airlines are quickly moving to paperless cockpits. Thanks to advanced systems in newer jets and tablet computers (like the iPad), we pilots do a lot less navigation work than we used to. One task many airlines still require is plotting ETOPS data on a paper chart. The nice thing about paper is that it doesn’t need batteries and still works after I spill coffee on it!
Below is an example of a plotting chart for a Los Angeles to Honolulu flight. We use a fresh chart for each flight. Using different colored highlighters is not only fun, but makes the chart easy to read. In the example, our planned route is highlighted in yellow and the 180 minute circles around our ETOPS diversion alternates are in green. This chart is custom printed for my airline; the ETOPS circles are the correct 180 minute no-wind distance for our Boeing 767 aircraft. There is a circle for each diversion airport we are approved to use. We simply highlight the circle (or arc) for the diversion airports our dispatcher selects for each flight.
Get out the highlighters, it’s time to color! Click chart for full-size image.
After we highlight the route and diversion arcs, we plot our ETOPS Entry Point where we fly outside of the 60 minute rule, and the Equal Time Point where the flight time to either diversion airport is the same. These points are provided to us on our computer generated flight plan. Knowing the ETP helps our decision-making in the event of an in-flight emergency. During the journey, we check our position about 10 minutes after passing each named intersection on the route. We take the present latitude and longitude from our navigation computer and plot that point on the chart. If the point is exactly on our yellow highlighted route, we know we are on course!
At the end of a flight, the ETOPS plotting chart makes a wonderful memento of the journey; suitable for framing. Usually, we throw it in the trash.
ETOPS: Engines Turn Or Passengers Swim?
An old airline joke is that ETOPS stands for “Engines Turn Or Passengers Swim.” It’s sort of funny (until you’ve heard it a few dozen times), but also misleading. ETOPS rules are not just for over water flights. Certain over land routes across Canada, Antarctica, Australia, Asia and Africa require ETOPS rules due to the lack of adequate diversion airports.
ETOPS for airplanes with more than two engines?
Why mention airplanes with more than two engines (like the 747 and A380) in an article about ETOPS? Doesn’t the T in ETOPS stand for Twin Engine?
The old acronym was: Extended-range Twin-engine Operational Performance Standards.
A few years ago, ETOPS rules were updated to include passenger airplanes with more than two engines. These long range jets routinely fly super-long routes over the Arctic, Antarctica and across the southern Pacific ocean. Government regulators felt that expanding ETOPS rules to include these aircraft would benefit safety. Thus, ETOPS now means: Extended Operations.
American Airlines Flies the Wrong Jet to Hawaii
Note: This ABC story incorrectly uses the obsolete acronym for ETOPS.
In late August of 2015, American Airlines mistakenly flew a non-ETOPS certified aircraft from Los Angeles to Honolulu. Was this a big deal? Yes, it was. Was passenger safety compromised? Statistically, there may have been a slight increase in risk to the passengers. Would I have been worried if I were on board? Probably not. The flight crew was ETOPS qualified. ETOPS dispatch, fueling, and navigation procedures were used, and the airplane likely had an ETOPS pre-departure maintenance check. The airplane in question was, no doubt, in tip-top shape. The problem was that the aircraft wasn’t listed on American’s ETOPS operating certificate so it wasn’t required to be in the airline’s ETOPS Maintenance Program.
American Airlines notified the FAA of the error while the aircraft was en route and immediately took steps to ensure a similar mistake would not happen again. After arriving safely in Honolulu, the aircraft was ferried empty back to LAX.
ETOPS is a game of risk analysis and statistics. The rules are designed to eliminate as much risk as reasonably possible to assure a successful flight. The farther an airline wants to fly from a diversion alternate, the more strict the maintenance requirements are to minimize risk. An aircraft in an ETOPS maintenance program should have a statistically higher probability of a problem-free flight than one that is not.
ETOPS Rules: Making extended operations safe!
ETOPS was first introduced in 1985. For over 30 years, the rules have succeeded in making long-range air travel for two-engine (and now four-engine) aircraft reliable and safe. Bravo, ETOPS!
Ken Hoke has been flying for over 30 years. He’s currently a Boeing 757 & 767 captain flying international routes for a package express airline. In his spare time, he writes AeroSavvy. Follow Ken on Twitter, Facebook,Instagram or YouTube.
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