"I know that people always talk about a balloon or air launching providing so little energy to orbit vs. ground launch. However, If I launch at a higher altitude, would not the lack of drag allow me to accellerate faster, and thus less gravity loss? "<br /><br />Yes and no. Your gravity losses would be slightly less, and if, for instance, you were lifted by balloon to 100,000 or more feet, you'd gain significant velocity while dropping which you would be able to translate into lateral velocity, so you'd be using your gravitational potential to get velocity, but only if you had sufficient aerodynamics to do so (such as having wings of some sort). However if you drop too far, you lose a lot of that energy in aerodynamic losses.<br /><br />The lack of drag at altitude does reduce your aerodynamic losses, not your gravity losses. Your gravity loss savings are because you are less deep in the gravity well, so, for instance, if your balloon is floating east at 100,000 feet at a few miles/hr, you calculate the boost you get from the earth's rotation differently: instead of launching 4,000 miles from the earth's center, you are launching 4,020 miles from the earth's center, so the force of gravity is slightly less AND your flight path circumference around the earth means you are going faster in absolute terms than you would walking along at a few mph on the ground. Thus:<br /><br />4,000 mile diameter X 2 X Pi = 25132.741228718345907701147066236 mile circumference <br />25132.741228718345907701147066236 / 24 hours = 1047.1975511965977461542144610932mph angular velocity at the equator at sea level.<br /><br />Conversely, at 4,020 miles, or 100,000 ft above the eath's surface:<br />4020 x 2 x pi = 25258.404934861937637239652801567 miles circumference<br /><br />25258.404934861937637239652801567 / 24 hours = 1052.4335389525807348849855333986 mph<br /><br />Thus, at 100,000 feet you are going 5 mph faster than being on the ground, when launching from the equator.<br />Not much difference.<br></br>