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In a German news article it was stated that the additional weight (Norwegian puts 291 passengers on their 787-8) leads to operations restrictions in Las Vegas when temperature conditions exceed 40°C.

Is the 787-8 really limited at 40°C? What would happen at airports that are not only hot but also high?

What are the temperature/altitude limitations for the 787-8 at MTOW in this specific case?

European low-cost carrier Norwegian Air will suspend its four Las Vegas routes in March, saying hot weather there has created performance issues for its heavily loaded Boeing 787 aircraft.

usatoday.com

aerotelegraph.com

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    $\begingroup$ NOT A DUPLICATE! This question asks abou the 787 & if the temperature limits are really as low as stated; the other question is a general discussion of how hot weather can be limiting, but it DOES NOT EVEN MENTION the 787. Related, yes, but certainly not a duplicate. $\endgroup$ – Ralph J Nov 23 '16 at 13:37
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    $\begingroup$ I've attempted to reword the question to A) make it more specific based on the comments, and B) show that it's not a dupe of the suggested on. If I've taken it off course, please revert. Also, @OP, please quote the source of your German news article. $\endgroup$ – FreeMan Nov 23 '16 at 14:19
  • $\begingroup$ @FreeMan thx. I have added the german news article. $\endgroup$ – YPA Nov 25 '16 at 16:37
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Norwegian’s heat issues stem from an unusually high passenger capacity aboard the Boeing 787-8 jetliners that the carrier uses on its Las Vegas routes. Most airlines operate the plane with an average of 200 seats, but Norwegian puts 291 seats for sale on the 787-8 aircraft to keep costs down as part of its low-cost model.

Given the weight of those additional Norwegian passengers and all that accompanies them, the airline this summer found close to 300 people on board, including crew, and its planes’ ability to take-off during high-temperature periods was sometimes limited.

reviewjournal.com

You see that Norwegian carries more people compared to other 787 operators. And they do indeed cite the passenger count as the reason.

Hot and high limitations are explained here, the biggest limitation for twin-jet planes such as the 787 is the ability to climb if an engine fails during takeoff.

The longest runway at Vegas' McCarran International Airport is 14,512 ft; the elevation is 2,181 ft.

enter image description here

From the 787 performance dispatch manual at 2000 ft pressure altitude and 42°C outside air temperature, we find the limiting factor is the climb limit weight, which is 195 tonnes (429,000 lbs).

The 787-8's maximum takeoff weight is 228 tonnes (502,500 lbs), that's a structural limit.

The 33-tonne difference is equivalent to 300 passengers (80 kg adult + 30 kg luggage and carry-on). Of course the plane won't be fully fueled, despite the huge distance, but you see how big the limitation is.

It gets even worse above 42°C. 30°C seems to be ideal. Vegas record high is 47°C, and the mean maximum in July is 44.7°C.

Why not depart from Vegas at night? Most probably due to slot restrictions. Waiting for the sun to go down means financial penalties, which is confirmed by the German news article.

Several times the airline had to move the flights to the cooler hours. It costs.— Google Translate

Vegas to Europe is a huge distance, and a direct-flight without a technical stop to refuel is Norwegian's only choice—evidently and understandably. Their low-cost model that favors filling all the seats over fuel is the limiting factor.

enter image description here

(gcmap.com) The four Norwegian routes, they range from 4,462 NM to 4,701 NM, London being ~4,600 NM.

enter image description here

(Source—PDF)

Fully loaded with payload, the range is limited to 2,700 NM for a takeoff from a 42°C Vegas.

18 tonnes are to be shed to make it to London, i.e., 163 seats will be empty, or 90 empty seats plus leaving behind 8 tonnes of freight—airlines do depend on freight for profit. So, the typical quoted 200 passenger capacity would work. But if Norwegian doesn't do freight, then they're not to blame for cancelling the four European routes during the summer heat.


Boeing PDF on how to read the payload/range chart.

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    $\begingroup$ OT from the original question (probably better suited to chat): I find it interesting that they'd suspend the flights instead of limiting the number of pax. I guess they just don't make money unless the plane's full... $\endgroup$ – FreeMan Nov 23 '16 at 15:17
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    $\begingroup$ Another OT, but I find it really surprising that there are 291 Norwegians wanting to go to Las Vegas every week :-) $\endgroup$ – jamesqf Nov 23 '16 at 18:46
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    $\begingroup$ I pity the poor souls onboard - crammed into most likely very compact seating for such a long flight. $\endgroup$ – Peter Kämpf Nov 24 '16 at 6:44
  • $\begingroup$ I'd agree with you @jamesqf. I've been there twice, and that's more than enough for me, but Vegas seems to hold one heck of a appeal for people. $\endgroup$ – FreeMan Nov 25 '16 at 19:38
  • $\begingroup$ Why isn't it full of fuel? $\endgroup$ – JBithell Aug 2 '17 at 18:59

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