Sunscreen on Plane Trips: A Dermatologist's 20-Plus-Hour Flight

I'm Dr. Hongseok Kim, a board-certified dermatologist with 21 years of practice and the medical director of VOS Dermatology Clinic in Gangnam, Seoul, right in front of Dosan Park. At VOS I see every patient myself, from the first consultation to the last treatment.

If you are flying long-haul, you may wonder whether you need sunscreen on plane journeys, or what else your skin needs in the air. This summer I tested my own routine on a trip to a seminar in Peru: more than 20 hours of travel with a connection in New York, then Cusco and Machu Picchu under very strong sun. This page is based on my YouTube video from July 2026; I rewrote it for readers abroad. The video above can be watched with translated captions.

Do you need sunscreen on a plane?

Short answer: the video does not measure UV inside the cabin, so I will not give you a number; what my skin showed on the flight was dryness, and that is what I treated on board.

I want to be straight about the limits here. I did not test window seats or cabin UV in this video. What I did document is how quickly the cabin air dried my skin early in the flight (in the video at 02:17), and what I did about it. Sunscreen became the main job the moment I stepped outside, and that part I cover in detail below. My general rule, which I repeat in the video (at 07:22), is that sunscreen is part of every day you go out, whatever the weather looks like.

Why mist alone does not help in dry cabin air

Short answer: in very dry air, water on the skin evaporates fast and can take more moisture with it, so you need something to hold it in.

Many people bring a face mist on board and spray it again and again (in the video at 04:07). It feels good for a moment, but the air is so dry that the water evaporates quickly and pulls moisture out as it goes. The same applies after a sheet mask: if you peel it off and leave your skin bare, it loses a lot of water (in the video at 02:49). The goal is not to add as much water as possible. It is to keep the water you add.

What I kept using: a few drops of oil

Short answer: after moisturizing, I put two or three drops of facial oil on top, and that is the step I repeated from the plane to the last night of the trip.

Before sleeping on the plane, I moisturized well and slept about six hours (in the video at 03:47). Somewhere over the US my skin felt a little dry again, so I repeated it. When I feel lazy, I put two or three drops of oil straight over the mask (in the video at 04:22). The oil makes a thin layer that slows evaporation, so the moisture lasts longer and I do not need to keep adding more once it has dried down.

You do not need a long product list for a flight: something that adds water and something that stops it escaping. If your skin reacts easily, my note on choosing face packs with the barrier first explains what I look for.

Clouds and heat are poor guides to UV

Short answer: the UV had not changed much when the clouds cleared; what I felt was heat, and UV itself does not feel hot.

At Sacsayhuamán, about 3,700 metres above sea level, the clouds suddenly cleared and the sun felt fierce (in the video at 06:30). Two hours earlier it had been overcast. It is natural to think the UV jumped at that moment, but my point on the spot was that it had barely changed (in the video at 06:53). The burning feeling comes mostly from infrared heat in sunlight, not UV (in the video at 11:44). UV does not hurt at first; you only notice later, when the skin starts to feel cooked.

How much, how often, and the spots I missed

Short answer: use a generous amount, reapply about every two hours outdoors, and include the neck and ears.

I applied sunscreen before going out, then topped it up once or twice with a compact and extra sunscreen (in the video at 06:37). Even with a large amount, I suspect it still was not quite enough. Reapplying about every two hours matters on a long day outside. I also made the mistake many people make: short on time, and not wanting sticky sunscreen on my collar, I skipped my neck, and I forgot my ears, which men in particular tend to miss (in the video at 07:47). For the detail on timing, see my video note on how often to reapply sunscreen.

UV index 11 at Machu Picchu, and the night care afterward

Short answer: at an extreme UV index, sunscreen alone cannot protect you, so avoid the midday sun first; afterward, a gentle one-to-two-minute cleanse, serum, a fragrance-free cream and a few drops of oil, the same as on the plane.

Machu Picchu sits at about 2,430 metres, and the day had not a single cloud (in the video at 11:32). The UV index read about 8 around 10 a.m. and climbed to 11, the extreme level, by around noon (in the video at 12:04). For comparison, in Seoul that summer it usually moved between about 5 and 8. At that level, no amount of sunscreen is really enough; the basic rule is to avoid going out in the strongest sun. The patch of neck I had left uncovered turned red. On the covered parts, sweat and dust stuck to the sunscreen, which made reapplying almost impossible. If you worry about the pigment strong sun can leave behind, my guide to Korean dark spot treatment explains the options.

There is no special trick to how I cleanse (in the video at 13:18). I lather the cleanser with only a little water, wash evenly for one to two minutes, add a touch more water if it starts to feel dry, and take a little more care at the tip of the nose and under the nostrils, where sebum and pores trap residue. Chemical (organic) sunscreens designed to wash off often come off in one round; mineral or hybrid formulas usually need a second cleanse (in the video at 14:57).

That evening my skin was red and warm. UV damage is not only about pigment; strong exposure can weaken the barrier (in the video at 15:36). So I moisturized right away: serum in two layers because the air was dry, then a cream. Any cream can work, but in conditions like these I choose a fragrance-free one (in the video at 16:31). I like cica textures, and PDRN products are another option. For sensitive skin, a product that leaves out likely irritants helps more than one packed with extras. I finished with two or three drops of oil (in the video at 17:05).

Ingredients such as vitamin C can come later. If your skin is peeling, though, they may irritate it further, so put barrier recovery first (in the video at 17:51). If you would like your products matched to how your skin actually behaves, VOS Skin MBTI was designed for that, and you can read creator experiences at VOS.

Wherever you travel, five minutes of the basics at the end of the day matters more than doing many things. Results vary from person to person, and what suits your skin is decided at an in-person consultation.

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Results, swelling and recovery vary from person to person. This page is general information from VOS Dermatology Clinic based on Dr. Kim's video and does not replace an in-person consultation.