Outside air temperatures can have quite an impact on the takeoff performance of planes. Hot air is less dense, which means that planes may need more runway to take off, and may need to restrict the number of passengers and cargo they can carry. While it’s rare, extreme heat waves can sometimes cause airlines to cancel flights out of certain airports.
Las Vegas can get very hot in summer, which consistently impacts the takeoff performance of planes. For most flights this isn’t an issue, given the long runway at Las Vegas McCarran Airport. Unfortunately even that isn’t enough for some airlines.
Hainan started flying to Las Vegas this past December, and it looks like they’re having their first issues with the Las Vegas heat. Hainan has adjusted their schedule for Las Vegas flights quite last minute between June 1 and October 1, 2017, due to heat. Per @airlineroute:
Currently their schedule for the route is as follows:
HU7969 Beijing to Las Vegas departing 2:45PM arriving 12:10PM
HU7970 Las Vegas to Beijing departing 1:00AM arriving 5:15AM (+1 day)
Meanwhile as of October they’ll switch back to the following schedule:
HU7969 Beijing to Las Vegas departing 2:45PM arriving 12:10PM
HU7970 Las Vegas to Beijing departing 2:10PM arriving 6:25PM (+1 day)
As you’ll notice, the eastbound flight timing isn’t changing, but rather only the westbound flight timing, meaning that the plane will be on the ground in Las Vegas for about 13 hours.
All of this is despite Las Vegas McCarran having a massively long 14,500 foot runway, which is the third longest in the US. My guess is that the 787 could take off from McCarran midday, but that it would be weight restricted, meaning they’d have to sacrifice cargo or passengers.
I suspect they could in theory take off later in the afternoon rather than waiting until after midnight, though that would ruin any connection opportunities in Beijing, so at that point they’re better off just delaying the flight so that it arrives in Beijing in the morning.
While I don’t think Qatar Airways will ever actually commence their planned Las Vegas to Doha flight, I wonder if they’d have to adjust their flight time as well, given that they have it scheduled to depart Las Vegas at 3PM. Then again, the flight is scheduled to be operated by a Boeing 777-200LR, which I believe has better takeoff performance. Furthermore, Qatar Airways is no stranger to heat, being based in Doha. 😉
This is all hypothetical anyway, since I doubt the flight will ever get off the ground.
It’s amazing the impact weather can have on flights…
KLAS is also around 2000 feet above sea level, which will also impact the takeoff performance
https://skyvector.com/files/tpp/1706/pdf/00662AD.PDF
@Peter Shenzheng airport, one of Hainan's hub
@Charles Yeah man. They do put some day flights in occasionally out of Tel Aviv. One time I flew TLV - JFK back in the day on TWA 747 in first class. Talking the late 90s here. And this WWF wrestler was so drunk he couldn't even walk on his own so three security people placed him into his seat and fastened the seatbelt for him . Guess they wanted him out of the country.
@Nathaniel . Philippines air tried the fifth freedom to Vancouver. Took it once plane was empty 777. Discontinued it not that long ago. No demand .
Phoenix Skyharbor gets even hotter. June & July and recently even August temps routinely get above 50C, and PHX is the official temperature for the city of Phoenix.
Most ME airports are busier at night than during the day, but I always assumed that was to make for more marketable departure and arrival times in Europe, North America an the Far East. And because the local residents probably have less clout in the ME than in affluent Western cities - aircraft noise all night would be beyond annoying.
Thanks for the notice. I actually booked this segment for someone to come from Asia this weekend, and now I have to rearrange it!
Israel does have many intercontinental flights at 1 AM but there might be scheduling or logistical reasons for this, They also operate Day flights that leave TLV at about 10 AM or even 3 PM.
@kq747 - You're quite right. Norwegian did shut down their 787 Vegas operations to European destinations (London Gatwick, Copenhagen, Stockholm, Oslo) for the summer being - citing the exact same reasons as Hainan. These Norwegian flights will recommence by october 2017. Somehow Norwegian wasn't able to rearrange there timetables to manage the summer heat.
@Peter That is Shenzhen airport.
Same thing in Israel. The flights leave at 1 or 2 am .
I am curious if there is enough demand to run a fifth freedom flight from Vegas to Vancouver and back?
The temps don't actually start coming down until about 7 pm in Vegas, so "later in the afternoon" is really more like "later in the evening", as compared to the middle of the night.
@Lucky what is the airport in the background? It is the most tarmac I have ever seen... looks really cool...
I believe Norwegian made a similar announcement a couple months back and that's just to Europe
Aircraft performance in Las Vegas is limited by the proximity to terrain, airport elevation (2,181ft ASL) , and when its hot, the density altitude. So for example, on the typical hot 105F days in LAS, say the baro is 29.55 with a relative humidity of 20%, can figure out that the density altitude would be around 6133 FT. So with that it would be like the plane is taking off at 6133ft vs 2,181ft.
https://www.aopa.org/training-and-safety/active-pilots/safety-and-technique/weather/density-altitude
...Aircraft performance in Las Vegas is limited by the proximity to terrain, airport elevation (2,181ft ASL) , and when its hot, the density altitude. So for example, on the typical hot 105F days in LAS, say the baro is 29.55 with a relative humidity of 20%, can figure out that the density altitude would be around 6133 FT. So with that it would be like the plane is taking off at 6133ft vs 2,181ft.
https://www.aopa.org/training-and-safety/active-pilots/safety-and-technique/weather/density-altitude
On a hot and humid day, the aircraft will accelerate more slowly down the runway, will need to move faster to attain the same lift, and will climb more slowly. The less dense the air, the less lift, the more lackluster the climb, and the longer the distance needed for takeoff and landing. Fewer air molecules in a given volume of air also result in reduced propeller efficiency and therefore reduced net thrust. All of these factors can lead to an accident if the poor performance has not been anticipated.
There's also the altitude of Vegas. Its 2030ft above sea level where Doha is 33 feet above sea level.
is there enough demand for this route ?
Almost all A380 departures in Dubai and Abu Dhabi are scheduled in the middle of the night for this reason.
I'm am sure this has been answered before (on here once before I think) but how does the Vegas summer heat affecting takeoff permfoance differ from hotter places like the Middle East where we don't hear about such issues?