FWIW, Isp is measured in seconds and by multiplying it times gravity, you get the exhaust velocity. I believe this was done to more easily compare rocket efficiency regardless of units of gravity.<p>It looks like you&#x27;re doing this calculation:<p>Isp * Gravity &#x2F; Gravity<p>If you&#x27;re trying to predict the hover duration, that will depend on the delta V of the vehicle. Then, a hover duration would be:<p>Delta v &#x2F; Gravity<p>Not sure what the expected delta V is for the Dragon though.