
Air India Taking Advantage of Tailwinds - obi1kenobi
https://blog.flightradar24.com/blog/air-india-taking-advantage-of-tailwinds/
======
toomuchtodo
I 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_...](http://www.boeing.com/commercial/aeromagazine/articles/2011_q2/4/)
and the fuel savings are substantial.

~~~
jacquesm
Every airline does this. A fuel estimation program I re-wrote in 1991 or so
had a whole bunch of tables and formulas related to correcting for the effect
of the jetstream on fuel estimates, you'd _have_ to do this otherwise when
you're going against the jetstream you're going to simply run out of fuel
before you reach your primary.

~~~
joezydeco
If you've ever flown one of United's 757s back from Europe, you know this
firsthand.

Has anyone else visited scenic Goose Bay, Canada recently?

~~~
kornish
Flew over Goose Bay going from Denver to Reykjavik in a 757, but that was
IcelandAir and not United. Beautiful!

~~~
dkroy
Haha, sorry this is going over my head. What is the significance of Goose Bay
in this conversation?

~~~
joezydeco
United gained a fleet of long-range 757s from the merger with Continental
Airlines. These are smaller planes (but ETOPS certified) with smaller crews,
which is good for United's bottom line.

757s can make it across the Atlantic, as long as conditions are good and there
are easy winds.

On the westbound return flights, and this happens more than United will care
to admit, the headwinds can be too strong and the flight needs to refuel in
Goose Bay before continuing to the United States.

This typically adds an unexpected 90 minutes to the flight, which can really
screw you up if you're trying to clear immigration and make your connecting
flight. You usually don't learn of this fate until you arrive at the terminal
for boarding.

~~~
niftich
Several sources substantiate this claim.

[1] (from 2012)
[http://www.wsj.com/articles/SB100014240529702034369045771529...](http://www.wsj.com/articles/SB10001424052970203436904577152974098241982)

[2] (from 2012) [http://www.cbc.ca/news/world/transatlantic-flights-forced-
by...](http://www.cbc.ca/news/world/transatlantic-flights-forced-by-wind-to-
land-for-fuel-1.1205359)

[3] (from 2015) [https://www.thestar.com/business/2015/01/14/strong-jet-
strea...](https://www.thestar.com/business/2015/01/14/strong-jet-stream-
forcing-airliners-to-make-labrador-retrievals.html)

[4] (from 2015) [http://mashable.com/2015/01/09/boeing-757-flight-
diversions/](http://mashable.com/2015/01/09/boeing-757-flight-diversions/)

~~~
joezydeco
Or I could have just shared the photos I took out the window from my last STR-
EWR flight. =)

------
ptaipale
Is 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."

------
hughes
I had always just assumed airlines did this... seems like an equivalent
headline to "shipping industry taking advantage of ocean currents".

~~~
ptaipale
Indeed - and the significance of tailwinds is larger than ships have with
ocean currents.

------
manav
I wonder if it was just a matter of getting permission to fly that route over
China / East China Sea.

~~~
jdhawk
That, and ETOPS planning.

~~~
greghendershott
You 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)

~~~
peachepe
ETOPS stands for Extended-range Twin-engine Operational Performance Standards

~~~
will_hughes
Yes, but the definition that greghendershott gives is the more amusing
version, and seems to be pretty common amongst the Aviation crowd.

------
dorfsmay
I 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.

------
ceedan
Better late than never, but why has it taken Air India so long to do this?

Edit: Answered in replies to manav

~~~
dingdongding
Because it is Air India. Slowest to adopt new technologies among other Indian
carriers.

~~~
swatkat
Then 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/...](http://economictimes.indiatimes.com/industry/transportation/airlines-/-aviation/air-
india-to-now-fly-daily-from-delhi-to-san-francisco/articleshow/53590740.cms)

------
aaron695
Is 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
Air 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...](http://airwaysnews.com/blog/2015/12/07/air-india-inaugurates-
nonstop-service-between-san-francisco-and-delhi/)

[2] [http://www.tribuneindia.com/news/nation/air-india-to-fly-
ove...](http://www.tribuneindia.com/news/nation/air-india-to-fly-over-pacific-
to-us-to-save-fuel/287021.html)

[3]
[http://dgca.nic.in/circular/ops/Ops05_2016.pdf](http://dgca.nic.in/circular/ops/Ops05_2016.pdf)

------
shabbyrobe
Does the additional speed increase the stress on the airframe or is that more
than offset by the reduced flight time?

~~~
matheweis
Neither; the airspeed (speed of aircraft relative to the air around it) is
roughly the same.

~~~
null0pointer
Additionally, 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.

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haalcion3
And 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)

------
myth_buster
Kudos 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
Even 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
They are nowhere near gliding range to an airport. They are hundreds of
minutes of flight time from landing, in fact ...

~~~
Johnny555
But 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.

~~~
brc
I 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.

~~~
codfrantic
MH17 was shot down over the Ukraine, you must mean MH370.

------
msandford
Doesn'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?

~~~
lucaspiller
Last 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/1...](http://www.telegraph.co.uk/news/worldnews/northamerica/usa/11337617/Jet-
stream-blasts-BA-plane-across-Atlantic-in-record-time.html)

I'd assume it's not worth it from SFO though, as the polar route is so much
shorter.

~~~
goatforce5
I 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!

------
highd
Did the jet stream change in some way recently? Or are they just now taking
advantage of it?

------
wst_
Hm... They read Seveneves? There's similar concept in there.

------
mankash666
Glad to see a government owned entity operating on science.

~~~
pif
Indeed! Why didn't they start before?

~~~
swatkat
[https://news.ycombinator.com/item?id=12740388](https://news.ycombinator.com/item?id=12740388)

------
gandalfu
Why 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?

~~~
ars
> 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
No 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.

------
sandworm101
15+ 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
What 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.

~~~
sandworm101
(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...](http://www.news-medical.net/news/20120207/New-guidelines-for-
travellers-to-avoid-DVT-on-long-flights.aspx)

(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.

~~~
mikestew
_When I was a kid flying london-vancouver it wasn 't unusual to see an entire
row empty. That's not a thing anymore._

I've been on domestic U. S. flights that have had multiple rows empty, to the
point that my rough math said the airline couldn't have been making a profit
on that flight. About a quarter of the time I'd get a row to myself. Those
days are long gone, of course. Now I can't even get an exit row months in
advance even if I want to pay for it.

~~~
coredog64
Airplanes need to be moved around. Maybe one leg is partially empty because
the plane needed to be somewhere for a D check.

When I was a dispatcher for a very small regional carrier, we might cancel a
flight that was too empty. More often we'd have to fly a nearly empty or empty
flight so that the plane would be where it needed to be for the next day.

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6stringmerc
Air 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
FYI: This isn't AIR PR, flightradar24 is a third party service.

