Old Jetpacks

Bell Rocket Belt - status: development canceled
patentimages.storage.googleapis.com/e2/e7/86/083aa4109dcd52/US3021095.pdf
1962 by Wendell Moore

Fuel - hydrogen peroxide
Flight time - 20 sec

It works by sending the pressurized fuel through a decomposition catalyst—in this case a series of fine-meshed screens made of silver. The peroxide instantly expands into superheated steam, producing a few hundred pounds of thrust at the exhaust nozzles. These are controlled by the pilot’s hand grips. There’s no aerodynamic lift; the thing stays aloft through the physics of brute force. It has the glide angle of an Acme anvil.

JB10 - status: retrofitted as new JB11 (see Fig. 35)
patentimages.storage.googleapis.com/c2/cc/4f/e885bd78655c95/US20170015419A1.pdf#page=28
2017 by David Mayman and Nelson Tyler

Fuel - kerosene or diesel
Flight time ~ 7 min