Urinary Incontinence Support Group
Urinary incontinence is the involuntary excretion of urine from one's body. It is often temporary, and it almost always results from an underlying medical condition. Stress, functional, and urge incontinence are the most common forms. Share with other support group members and learn from their stories and experiences.
You can also put a baby diaper or one of the male pads or poise pads inside the diaper and when it is wet just take it out and the diaper is still mostly dry. This will work if you use a diaper with the cloth outer cover and velcro tabs. You can also wear two diapers and just remove the wet one. I wear like a photographers vest that has large pockets that will hold extra pads and wipes.
On the larger planes on the international flights there is often a handicapped bathroom and that does give you a bit of extra room to change.