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February 22

Boeing 777 range with 1 engine

A recent news item [1] reports that a Boeing 777 had an engine failure. How far can such a plane fly on only one engine? I read the Wikipedia article, but did not see that info. If the engine failure had happened midway between US mainland and Hawaii, could the plane have enough distance to reach an airport? RudolfRed (talk) 01:10, 22 February 2021 (UTC)[reply]

Flying a twin-engined airliner (such as the 777) further than 1 hour away at its cruising speed with one engine failed from a possible landing field is known as "extended twin operations", "extended operations", or ETOPS for short: the concept has also been extended to aircraft with more than two engines, and usually refers to flights at least partially over water or remote land terrain.

Every civil airliner is given an ETOPS rating that gives the upper limit of the permitted flying time with one engine out that it is allowed to get from any airfield(s) it could divert to and land at. No flight plan should be made or accepted that breaches this limit.

The rating for the 777 was originally ETOPS-180: this was later increased to ETOPS-207 in at least some circumstances: bear in mind that as with most types of airliner, there are several variants with different capabilities. My extremely rough estimate is that this would translate to about 2,000 miles, but doubtless more knowlegeable responders can and will correct this. Of course, this is an indication of what a flight plan should stay within, not the actual capability of the aircraft, which presumably is somewhat greater.

According to various issues of Flight Magazine I read some years ago, airline personnel amongst themselves refer to ETOPS as "Engines Turning Or Passengers Swimming." {The poster formerly known as 87.81.230.195} 2.125.75.168 (talk) 01:56, 22 February 2021 (UTC)[reply]

Interesting. Thanks for the reply RudolfRed (talk) 02:10, 22 February 2021 (UTC)[reply]

Range is not affected as much as speed. As an example, I once opted to get two free round-trip tickets. I was in Hawaii, heading home to New York. My flight was on TWA. The jet had a broken engine. They couldn't repair it in Hawaii. They had to get it back to mainland. So, they told passengers that we could get free tickets if we flew back in the plane with one engine or we could wait for the next day's flight and fly standby. It may take up to 3 days of waiting to get back. Because there was one engine instead of two, the plane flew much slower, but had pretty much the same range. I discussed this many years later with an aircraft mechanic and he said that theoretically it would have the same range, but there are three circumstances that shorten it. One is fuel. Each wing is a fuel tank and you won't get all the fuel from one side to the other. So, there's some fuel that won't be used, shortening range. I personally think that is odd, but I'm not an aircraft mechanic. The second is that crippled aircraft are slower and fly lower. They are in thicker atmosphere, which increases drag, which lowers range. Finally, thrust from one side and not the other tries to turn the plane. The plane has to constantly be turned back against this to go straight. Again, that increases drag, which lowers range. He then told me that when TWA started, they had a test for the first aircraft. It had to fly from Kansas City to Denver on one engine to prove that if an engine fails, they can still make it to the next airport. 97.82.165.112 (talk) 11:32, 23 February 2021 (UTC)[reply]

Contact email for the company Alkè

Hi,

So I'm not sure if this is actually a valid place to ask this question... but I thought I'd try it at least :) Does anyone know what the contact email for Alkè is? I looked on their website, and they only have a form for emails in the contact section... I want to just send them an email using my email client. If this question doesn't belong here, my apologies :) Regards, DesertPipeline (talk) 13:49, 22 February 2021 (UTC)[reply]

On several pages (e.g. here) they mention the e-mail address info@alke.com. --Lambiam 14:46, 22 February 2021 (UTC)[reply]

Oh, hey, thank you :) I didn't think to check the privacy policy page – I only checked the contact page. Thanks again for your help :) DesertPipeline (talk) 14:48, 22 February 2021 (UTC)[reply]

Many companies avoid publishing their email address to reduce spam from email-address harvesting. Sending an email to info@ followed by the company website name will usually work. But filling out the form may work better by directing your message to the appropriate department.--Shantavira|^{feed me} 15:15, 22 February 2021 (UTC)[reply]

When I couldn't find an email address on the contact page I tried sending an email to "contact@alke.com" – as you can imagine, that didn't end up working out :) Luckily the email address that Lambian provided was the right one and I got a response :) DesertPipeline (talk) 15:21, 22 February 2021 (UTC)[reply]