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Maisy, season 1 episode 27 «Plane»: air date March 4, 1999. Episode overview, season trailer and the cast of Maisy.
Maisy and Cyril are making paper aeroplanes. Maisy's aeroplanes can't fly very well, and lands in the sink. Cyril's aeroplane is magnificent - it flies beautifully through the house, out of the window and all round the garden.