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Considering launches from the two major cosmodroms are launched into inclinations quite far from equatorial, and that inclination change in LEO is awfully expensive in terms of delta-v, what trajectory do rockets take to deploy satellites into a low orbit above Earth's equator?

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The answer is that they do not, the delta-v cost is as you state high. Plesetsk is 63 degrees north, and Baikonur is 43 degrees. Plesetsk is actually so inclined that it costs less to do a bi-elliptic manoeuvre, meaning that you accelerate almost up to escape velocity, do the inclination change at a great distance, and then fall back and brake into low Earth orbit. To have a satellite in low equatorial orbit, you have to launch from the equator or close to it.

For that matter, almost no satellites are launched to equatorial LEO from Cape Canaveral either.

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  • $\begingroup$ I'm not sure I understood your last sentence: Did you mean "almost no satellites are launched to equatorial LEO" or did you miss a comma? $\endgroup$ – SF. Dec 28 '15 at 1:05
  • $\begingroup$ @SF Yes, it is "almost no satellites are launched to equatorial LEO" $\endgroup$ – Hohmannfan Dec 28 '15 at 10:52
  • $\begingroup$ ...and I guess ESA is in the best situation, with the Guiana Space Center mere 5 degrees from the equator. $\endgroup$ – SF. Dec 28 '15 at 18:14
  • $\begingroup$ That's right! But even a 5.2 degree inclination change in LEO is 700m/s $\endgroup$ – Hohmannfan Dec 28 '15 at 18:57
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    $\begingroup$ I imagine that can be achieved much cheaper by launching towards the equator and then changing the inclination long before reaching orbital velocity, when the horizontal velocity factor is still quite low. $\endgroup$ – SF. Dec 28 '15 at 19:22

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