Hydration is key for a long haul flight and important for skin whether you are in a hot or cold climate. Skincare brand Elemental Herbology specialises in treating skin in different seasons and environments because the weather can completely change the way your skin acts and feels. I'd recommend its Soothing Oil-Free Facial Hydrator SPF 12, £36, which hydrates skin whatever the weather, but also works to prevent breakouts which tend to occur on flights or when switching from one climate to the other. For a more purse friendly alternative try La Roche Posay's Hydraphase XL, £16 which expertly hydrates and soothes skin – it’s great for really dry skin types.
Always carry on a face mist, so you can pep up skin during the flight - air conditioning wreaks havoc on complexions. I love Caudalie Grape Water, £7 for 100ml, so you can take it on board.
When it comes to eye cream I don't think you can beat Aveda Tourmaline Charged Eye Creme, £27. Sadly I found out it has been discontinued, but you can still buy it on the Beautique.com website. It instantly brightens my eye area and in just a couple of weeks reduces dark circles and pesky fine lines. It's the only eye cream I've ever stuck by - flight or no flight; as soon as I find a replacement good enough I’ll let you know.