| Rotational power must be transmitted from pilot’s legs to a propeller at the rear of the blimp. Furthermore, the propeller tilts along the up-down axis in order to provide vectored vehicle thrust up and down. | A hollow, rigid keel runs along the bottom of the blimp within which a chain travels from the pedal crankshaft along many pulleys (or through the envelope) to a chain gear next to the propeller |
| The chain gear next to the propeller is connected to a bevel gear which transmits the power through a right angle to the propeller axis. Remember that the propeller is allowed to tilt up and dip down, probably about the axis of the chain gear, in order to achieve vectored thrust. | Here is the location where a shaft drive would be installed: between the chain gear and the propeller hub. The shaft drive, including the housing, would be ideal as it is sized already for human power inputs and rotational speeds. As with any human powered aircraft, it is possible that “lightening holes” be introduced into any off-the-shelf hardware. |
Here are some examples of bicycle shaft drive units, shown from the website of Sussex corporation in Taiwan:
