This simple calculation would help Alex and his

team to work out how much thrust would need

to come from pedal power to overcome the

drag and the weight in order for the wing to be

moving through the air fast enough to generate

the lift required to get the HPA airborne.

Weight is a force (F)

created by gravity.

Gravity supplies the

acceleration (a) and

your mass (m) is you.

In outer space, where

there is zero gravity, you

would still have your

mass (all your bits would

still be present), but your

weight (the force F)

would be zero. In space

you are weightless.