I have an Eagle Book of Hobbies and an Eagle Book of Balsa Models somewhere which has the parkland peril in it. A profile Boy's Own rocket ship hanging on two bent up paper clips from a fine thread strung between two trees. The little Jetex 50c clips on the bottom. The naughty schoolboy creeps out from behind a tree, lights fuse and watches as old biddies run screaming from the woods!
We laughed, bless us!
The Jetex Bluebird was not, shall we say, unidirectional, but great fun. We used to light 'em up and aim for kids with Eezibilts in the hope of conflagration.
No such luck, though.
Ah happy days in Valentine's Park, Ilford.
Regards,
Vintagent