I am often asked to build a powered aeroplane and I wanted an excuse to buy a 'super capacitor' so I built another one of my chuck gliders and glued an electric motor from a vibrating toothbrush on the front. The propeller is made from a strip of aluminium cut from a drinks can.
I charged the capacitor for about 5 minutes using 2 AA batteries before each flight. This gave it enough power to cross my garden with a slight climb in it's flight path. I don't think it would do well in windy conditions and would probably do better indoors.
A proper propeller would improve performance significantly.
The width and length of the plane were just based on what the biggest section was that I could cut from the plates. The coffee stirrer is 17cm long. Each wing is 15.5cm long and 6cm wide. The tail is 12cm tip to tip and 3cm wide
The main components are:
Wooden coffee stirrer
Short length of solder or similar as a balance weight
You would get better results buying a proper propeller for small electric planes online.
Plastic jewellery bead for the bearing
Short plastic tube - mine came from a hand wash bottle pump
This motor came from a vibrating toothbrush or you might try a pager motor. I have lot's of old Oral B Pulsar toothbrushes that I have saved over the years. However I would not buy the toothbrush just to get the motor, they are expensive toothbrushes and you can get better more powerful motors for much LESS money if you buy online from somewhere like eBay or Amazon. I suggest you search for "3.7V Coreless Motor"