Air travel is a form of travel in vehicles such as helicopters, hot air balloons, blimps, gliders, hang gliding, parachuting, airplanes, jets, or anything else that can sustain flight.
We must try to perform our obligatory Prayers (Salah) where ever we are including in an airplane. We must try to find a suitable place to stand for few minutes to pray.
The direction of Qibla can be known through the cabin crew who usually ask the pilot about the direction of Makkah. You can also see the map of the journey and check where is Makkah from your flight route. There are also Qibla applications which can help.
In case you have no way at all to know the Qibla direction, you must pray facing any direction. After praying towards any direction which is obligatory , it will be recommended (not obligatory) to pray towards the other three directions.
If you are for any reason not allowed to stand to pray in the airplane, you should pray in sitting position on your seat.
The main point here is that the obligatory Prayers Must be performed in the best possible way within its time and it is not allowed at all to leave praying the obligatory Prayers till its time goes away.
The Ka’ba is situated on the center of the earth. This is a miracle which has been confirmed and admitted by non Muslim scientists. No birds and planes can fly over the Ka’ba because of that miracle.
Since you will stay over 10 days, you will pray full
This would all depend on what time of the day/night you are travelling, and when your are leaving your place of iqamah, which is the place of your residence or where you have intended to stay for ten days or more.
If you leave your place of iqamah after noon time, you must stay fasting. If you leave before noon, you must break your fast once you exceed the boundaries of the place of your iqamah.
As for the next day, if you arrive before noon, you are able to stay in the state of imsak, from Fajr time, until you reach your destination, and then adjust your intention and make it intention of wajib fasting.
If you arrive after noon, then you will not be able to fast for that day.
And Allah knows best.
You are a traveler in this case and you can't fast.
But if you intend to stay in one place for at least 10 days then you have to offer your prayers completely and also fast.
Note that if you prayed a 4 unit prayer and you changed your mind (not to stay there for 10 days, then you have to pray completely and fast as many days as you will be there, like the next 2 days...)
Salaam alaykum, you can pray your dhuhr salah before maghrib once you arrive in LA. You need to pray maghrib-'isha, and fajr on the flight back to London. If you can pray dhuhr-'asr before maghrib in London, then you can do that, as maghrib is now approx 6:00 pm.
You may pray Zuhr and Asr on the plane, or after you land in LA before Qaza.
In the return case you must pray at least those Salats that would become Qaza if you wait until landing.
You will need to do your own calculations to determine where you will be in your flight at the average time for prayers and to determine if you need to pray or not. There are Apps for iOS and Android and also a web portal at https://www.halaltrip.com/prayertimes/inflight/ which may assist you in these regards.