How do I make wudu on a plane?

Before you board

The easiest trick is to make wudu at the airport just before boarding, and put on your socks while you are in a state of wudu. The Prophet ﷺ said about his leather socks, "Leave them, for I put them on while I was pure" and then wiped over them (Sahih al-Bukhari 206). Many scholars apply this to normal socks too. That way, if your wudu breaks during the flight, you only need to wash your face, arms and wipe your head and socks. See Do I have to take off my socks every time I make wudu?

Step by step in the airplane toilet

1. Take a small water bottle or travel spray bottle with you, or use the tap.
2. Make your intention and say "Bismillah".
3. Rinse your mouth and nose once with a small amount of water.
4. Wash your face, then each arm up to the elbow. Once is enough; three times is sunnah, not required.
5. Wipe your head and ears with wet hands.
6. Wipe over your socks, or wash your feet if you're not wearing any.
7. Wipe the sink dry with paper towels so the next person isn't left with a wet mess.

The Prophet ﷺ made wudu with very little water, about one mudd, roughly two-thirds of a litre (Sahih al-Bukhari 201). Plane toilets have plenty for that.

If water isn't possible

On a short flight with the seatbelt sign on, or if crew ask you not to use water, scholars differ. Some allow tayammum by striking a clean surface; others say there's no earth on a plane, so you pray in your current state when the time is running out and some recommend repeating it later. Allah does not want hardship for you:

See How do I do tayammum?

Then pray

You can pray in your seat or in a quiet space near the galley if crew allow. See Can I pray on a plane?