What to do for birthday?

[Ashley887]

My parents are coming to visit over my dad's 60th birthday. In lieu of giving him a gift, I want to do some sort of activity together. My dad enjoys the outdoors and is still reasonably physically-able. He really likes boats and airplanes. Does anyone have any ideas for a fun birthday activity we can do? My parents will also be staying on Bintan for a few days- are there any companies they can use to charter a sailboat or go for a biplane ride?