Analysis of information sources in references of the Wikipedia article "Equator" in English language version.
Equatorial launch sites offered certain advantages over facilities within the continental United States. A launching due east from a site on the equator could take advantage of the earth's maximum rotational velocity (460 m/s (1,510 ft/s)) to achieve orbital speed. The more frequent overhead passage of the orbiting vehicle above an equatorial base would facilitate tracking and communications. Most important, an equatorial launch site would avoid the costly dogleg technique, a prerequisite for placing rockets into equatorial orbit from sites such as Cape Canaveral, Florida (28 degrees north latitude). The necessary correction in the space vehicle's trajectory could be very expensive - engineers estimated that doglegging a Saturn vehicle into a low-altitude equatorial orbit from Cape Canaveral used enough extra propellant to reduce the payload by as much as 80%. In higher orbits, the penalty was less severe but still involved at least a 20% loss of payload.
Equatorial launch sites offered certain advantages over facilities within the continental United States. A launching due east from a site on the equator could take advantage of the earth's maximum rotational velocity (460 m/s (1,510 ft/s)) to achieve orbital speed. The more frequent overhead passage of the orbiting vehicle above an equatorial base would facilitate tracking and communications. Most important, an equatorial launch site would avoid the costly dogleg technique, a prerequisite for placing rockets into equatorial orbit from sites such as Cape Canaveral, Florida (28 degrees north latitude). The necessary correction in the space vehicle's trajectory could be very expensive - engineers estimated that doglegging a Saturn vehicle into a low-altitude equatorial orbit from Cape Canaveral used enough extra propellant to reduce the payload by as much as 80%. In higher orbits, the penalty was less severe but still involved at least a 20% loss of payload.