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Air India Taking Advantage of Tailwinds
- mankash666 10y agoGlad to see a government owned entity operating on science.
- pif 10y agoIndeed! Why didn't they start before?
- dingdongding 10y agoBecause it was government owned entity from INDIA
- swatkat 10y agohttps://news.ycombinator.com/item?id=12740388 https://news.ycombinator.com/item?id=12740388
- msandford 10y agoDoesn't this sort-of imply that they could do the same thing the other way also? Or are they already doing that by catching the polar jetstream at the top of the polar route?
- tantalor 10y agoThe wind goes the other way that way.
- tempestn 10y agoAnd so would the plane. That's why it's longer, so the Polar route is generally preferred.
- lucaspiller 10y agoLast year a flight from JFK - LHR made a record crossing of 5 hours and 16 minutes by taking advantage of the jetstream: http://www.telegraph.co.uk/news/worldnews/northamerica/usa/11337617/Jet-stream-blasts-BA-plane-across-Atlantic-in-record-time.html http://www.telegraph.co.uk/news/worldnews/northamerica/usa/1... I'd assume it's not worth it from SFO though, as the polar route is so much shorter.
- United857 10y agoI fly SFO-LHR often. Sometimes the flights do actually take a southerly route (overflying New York) to take advantage of the wind. It's all a tradeoff of increased distance vs increased speed, depending on wind patterns on that day.
- goatforce5 10y agoI was on a BOS-LHR flight once that picked up a good tailwind and we arrived well ahead of schedule, only to sit in a holding pattern for 30-ish minutes so we could land after the airport noise restrictions were loosened at 6am. Super frustrating to fly over your house repeatedly when all you want to do is get home!
- sandworm101 10y ago15+ hours in the air. In economy. That isn't healthy. I'm wondering if we eventually get to the point that health agencies speak up, that there is too much risk in having people sit in tiny chairs for such periods. When I was a kid I did lots of 8+ hour flights (YVR-London, London-middle east). Seats were bigger then. Now I see old people sitting in tiny seats and wonder how many will leave the flight with a DVT injury? How many will be in hospital with flu the next day? If sitting is the new smoking, these flights are like sleeping inside a chimney.
- soared 10y agoWhat is your suggested alternative.. force every plane to land half way and take a coffee break? Also, aren't they the same planes and seats as decades ago? We don't replace planes very often, neither do they just sneak in another seat on every row.
- untog 10y agoI don't think they are the same seats - they get replaced - but they are pretty much the same size. Legroom, on the other hand, has definitely decreased.
- greglindahl 10y agoActually newer seats have increased legroom by making the seats thinner. Of course airlines have moved them closer together.
- sandworm101 10y ago(1) Yes. I could see maximum times for flights if one could draw a link between long flights and poor health outcomes. Speaking of which... "One person in 4,600 experiences a symptomatic VTE in a month following a flight of four hours or longer, and only a minority of those are serious." http://www.news-medical.net/news/20120207/New-guidelines-for-travellers-to-avoid-DVT-on-long-flights.aspx http://www.news-medical.net/news/20120207/New-guidelines-for... (2) The airframes aren't new. but the seating arrangements sure are. And modern tech, big-data, means far more flights are booked solid. When I was a kid flying london-vancouver it wasn't unusual to see an entire row empty. That's not a thing anymore.
- manav 10y agoI wonder if it was just a matter of getting permission to fly that route over China / East China Sea.
- jdhawk 10y agoThat, and ETOPS planning.
- kylehotchkiss 10y agoYeah, much of the assumptions here seem to not account for ETOPS rules
- CPLX 10y agoIn the context of ETOPS180 there isn't much of the northern hemisphere that's off limits to you.
- greghendershott 10y agoYou can try various ETOPS (Engines Turn On or Passengers Swim) times on the Great Circle Mapper: http://www.gcmap.com/mapui?P=DEL-SFO&MS=wls&DU=mi&E=90 http://www.gcmap.com/mapui?P=DEL-SFO&MS=wls&DU=mi&E=90
- _vn5r 10y agoETOPS stands for Extended-range Twin-engine Operational Performance Standards
- will_hughes 10y agoYes, but the definition that greghendershott gives is the more amusing version, and seems to be pretty common amongst the Aviation crowd.
- deleted 10y ago[deleted]
- toomuchtodo 10y agoI hope someone is writing some code that'll automatically integrate winds aloft forecasts into flight plans! The fuel savings (and time in the air) ROI across the entire air travel industry would by yuuuuge, and the only cost is development time (I say "only" as you're not having to build any new physical machinery). EDIT: Boeing already offers this service it appears: http://www.boeing.com/commercial/aeromagazine/articles/2011_q2/4/ http://www.boeing.com/commercial/aeromagazine/articles/2011_... and the fuel savings are substantial.
- manav 10y agoBoeing already does this, I think AI just started to subscribe to it.
- toomuchtodo 10y agoI was unaware. Thank you!
- greglindahl 10y agoI'm stunned that they don't do that already. They've had specialized weather codes that give more accurate jet stream forecasts for a couple of decades now... Edit: This is the code: https://en.wikipedia.org/wiki/Rapid_update_cycle https://en.wikipedia.org/wiki/Rapid_update_cycle
- pavel_lishin 10y agoI'm surprised we don't have live data for this.
- greglindahl 10y agoWe mainly get data from where planes and weather balloons travel -- there's no way to get detailed data about the entire volume of the atmosphere (although it's being worked on.) As a result, models get initialized by the output of previous models, and the main thing that keeps them somewhat close to reality is the data we collect on the surface. Also, since a plane flight takes several hours, you really need a prediction to pick the correct path, not just the data right now. [3D satellite data for temperature and water vapor: https://en.wikipedia.org/wiki/GNSS_radio_occultation https://en.wikipedia.org/wiki/GNSS_radio_occultation but I don't think there's an equivalent for wind speed other than the very limited doppler radar.]
- myth_buster 10y agoKudos for ingenuity but from my understanding, flying over land is preferred than over an ocean as there are options available in case of emergency. So isn't this jeopardizing flights for fuel savings?
- United857 10y agoEven over the ocean, flights in airliners are planned so they're no more than 1-3 hours from the nearest diversion point. https://en.wikipedia.org/wiki/ETOPS https://en.wikipedia.org/wiki/ETOPS
- URSpider94 10y agoThey are nowhere near gliding range to an airport. They are hundreds of minutes of flight time from landing, in fact ...
- Johnny555 10y agoBut how often do airplanes glide into the ocean because they had some failure and couldn't reach land? Seems like an insignificant risk, and cutting the flight time by 10% might do more to reduce risk than staying over land.
- kijin 10y agoLand routes also tends to have certain hazards that generally don't exist in the open sea, such as 8km+ mountains, idiots with missiles, and much busier air corridors around major cities. That might balance out the risk of an ocean crossing.
- brc 10y agoI think there is only one case, and that was because if a hijacking. The plane broke apart on landing. It was caught on video by someone on the beach. Of course, we don't know what happened to mh17, which might have also glided into the ocean.
- hughes 10y agoI had always just assumed airlines did this... seems like an equivalent headline to "shipping industry taking advantage of ocean currents".
- ptaipale 10y agoIndeed - and the significance of tailwinds is larger than ships have with ocean currents.
- ptaipale 10y agoIs this actually a new thing? I was under the impression that carriers and captains have taken the jetstreams into account when planning their routes for decades and it is systematic. Cabin announcements have mentioned this already in 1990's: "Ladies and gentlemen, our flight path takes us today further to the north so we'll be passing Vorkuta and approach the Lake Baikal from north before entering Mongolian airspace. This way we can utilize tailwinds and our estimated time of arrival in Beijing is about half an hour ahead of the schedule."
- aaaadd 10y agoهلا
- highd 10y agoDid the jet stream change in some way recently? Or are they just now taking advantage of it?
- ceedan 10y agoBetter late than never, but why has it taken Air India so long to do this? Edit: Answered in replies to manav
- deleted 10y ago[deleted]
- dingdongding 10y agoBecause it is Air India. Slowest to adopt new technologies among other Indian carriers.
- swatkat 10y agoThen why other operators are not doing this long-haul nonstop route? This flight plan has been proven successful for Air India, they run it thrice a week at 88% occupancy. Now, they'll be flying this route daily[1]. [1] http://economictimes.indiatimes.com/industry/transportation/airlines-/-aviation/air-india-to-now-fly-daily-from-delhi-to-san-francisco/articleshow/53590740.cms http://economictimes.indiatimes.com/industry/transportation/...
- swatkat 10y agoAlso: https://news.ycombinator.com/item?id=12740388 https://news.ycombinator.com/item?id=12740388
- shabbyrobe 10y agoDoes the additional speed increase the stress on the airframe or is that more than offset by the reduced flight time?
- matheweis 10y agoNeither; the airspeed (speed of aircraft relative to the air around it) is roughly the same.
- null0pointer 10y agoAdditionally, most of the stress on an aircraft is from pressurisation/depressurisation. So most flights cause similar amounts of wear on the aircraft regardless of flight time.
- deleted 10y ago[deleted]
- gandalfu 10y agoWhy is the plane going faster? Less resistance from the wind due to the smaller speed difference? I don't believe the air can push the airplane... Any physicist care to explain?
- facetube 10y agoIf you're moving 20 m/s in a tank of water that's moving along the ground at 2 m/s, your ground speed is 22 m/s.
- ars 10y ago> I don't believe the air can push the airplane... Before I reply to you, first tell me if this is some sort of strange form of trolling, or do you really believe that?
- gandalfu 10y agoNo trolling, It seems to me the airplane does not have enough surface area (sail) to be pushed by the wind. My final conclusion is relative movement, the jet stream is moving at speed X vs the ground and the airplane at speed Y vs the surrounding wind, the airplane moves then at speed X+Y vs the ground. My question is now, a GPS based speedometer will read X+Y speed. A wind based one will read just X. I should have asked if the airplane is moving faster vs the surrounding wind.
- hyperknot 10y agoNot a physicist, but if a plane is flying by 900 km/h compared to the air, and the air is moving by 100 km/h relative to Earth, it can make the plane fly 800 or 1000 km/h relative to Earth, can't it?
- Manishearth 10y agoThe airplane works by pushing the air and gets a speed relative to the air. If the air is moving, the ground speed will need that speed added. Ignoring the airplane pushing the air, an airplane can be pushed by wind too. An airplane on the ground would not be pushed by air, because of friction. If you somehow managed to make an airplane float (without using the engines), this is no longer a factor; quite the reverse. The airplane will be dragged along by the air. "big things can't be pushed by air" is ground-logic, due to friction against the ground.
- aaron695 10y agoIs this just an example of India bureaucracy and more proof of the lost chances of most of the BRICS? Why wasn't this done on day one?
- swatkat 10y agoAir India DEL to SFO nonstop flight was launched in December 2015[1]. So, it's a relatively new route for Air India, and it has been very successful due to its non-stop nature. This change in route (flying over Pacific) was announced back in August 2016[2] itself. They're doing incremental optimization of route plan, nothing wrong in it. There might be permits/permissions required to fly over Chinese air space too, which might have been resolved by now[3]. [1] http://airwaysnews.com/blog/2015/12/07/air-india-inaugurates-nonstop-service-between-san-francisco-and-delhi/ http://airwaysnews.com/blog/2015/12/07/air-india-inaugurates... [2] http://www.tribuneindia.com/news/nation/air-india-to-fly-over-pacific-to-us-to-save-fuel/287021.html http://www.tribuneindia.com/news/nation/air-india-to-fly-ove... [3] http://dgca.nic.in/circular/ops/Ops05_2016.pdf http://dgca.nic.in/circular/ops/Ops05_2016.pdf
- thetruthseeker1 10y agoI dont think there is any greater lesson or theme here about lost chance of BRICS of anything. I think the world is ever changing and there is always newer opportunities that show up to capitalize from. India is a big country/ship and is harder to steer quickly. In the last 25 yrs, India's GDP growth rate has not fallen much below 4% (averaging more than 6%). India is achieving near 100% literacy rate below a certain age demographic, it has a good space program, there is good encouragement for education and free enterprise, I reckon India is doing many things right.
- 6stringmerc 10y agoAir India PR Person 1: How do we frame this airspace deal with China to make us look really good and not just playing catch up? Air India PR Person 2: Talk up the jet stream time savings! Air India PR Person 1: Brilliant!
- zeusk 10y agoFYI: This isn't AIR PR, flightradar24 is a third party service.
- wst_ 10y agoHm... They read Seveneves? There's similar concept in there.
- haalcion3 10y agoAnd for those that missed it, here's another way to reduce fuel usage: plasma. https://news.ycombinator.com/item?id=12365723 https://news.ycombinator.com/item?id=12365723
- dorfsmay 10y agoI don't know why, and even though the net effect is the same, I think it's really cool that instead of going back and forth, like most flights, this plane (and its passengers) keeps going in the same direction and goes once around the earth on each "return" flight.