In order to find his weight, let's analyze the formula for the gravitational force between two bodies:
![F=(GMm)/(d^2)](https://img.qammunity.org/2023/formulas/physics/college/qqbvjpv2h60tff7jujnwf3xgw12s3323kk.png)
We can see that the gravitational force is inversely proportional to the square of the distance.
So, if the distance doubles, that means the gravitational force will decrease by a factor of 4.
Joe's weight on Earth is 720 N, so his weight on the aircraft would be:
![W=(720)/(4)=180\text{ N}](https://img.qammunity.org/2023/formulas/physics/college/tqbyd7nm7ueax5k0jyu4snxka9kllzohwx.png)
Joe's weight would be 180 N.