5 ms·

Note that this launch wasn't from the equator, because this constellation needs to overfly hurricanes. It's fairly uncommon for LEO satellites to want to be at

• Retric 10y ago
  Launching from the equator is useful for a wide range of orbits as a component of the final vector 1600km/h is really not that fast and your final orbit crosses the equator anyway. The only issue is if the ideal launch point is not over the ocean. Also, there is a wide band near the equator with close to optimal velocity.
  • greglindahl 10y ago
    Yeah, I suppose my comment was not the most clever. In this case they were only launching 1/2 the max payload so performance wasn't really an issue anyway.
  • bsdetector 10y ago
    It's about 5% of the final velocity, but that's way more than 5% fuel savings because you don't have to suspend million of pounds against gravity for a minute and also don't have to accelerate that fuel. For example Saturn V used 40% of its total fuel to get up to this speed. That's a huge savings. Unless I am reading the data incorrectly: http://www.braeunig.us/apollo/SaturnV.pdf http://www.braeunig.us/apollo/SaturnV.pdf
    • Retric 10y ago
      Vector addition means you save energy, but not one to one. EX: if you add 1 going north and 1 going east then your final vector is 1.414 going north east. So, it might only be worth 1% or 5% of the final velocity.