Are inclination manoeuvres and eccentricity control the same thing or different things.?

Question

please tell me are inclination manoeuvres and eccentricity control the same thing or different things.

I read somewhere online that :when fuel approaches depletion, satellite operators may decide on omitting inclination manoeuvres and only control eccentricity. This could prolong the life-time of the satellite as it needs less fuel.

I was thinking inclination manoeuvres must involve changing of eccentricity.

Thanks in advance.

Answer 1

Inclination refers to the plane of the orbit with relation to Earth's equator. Eccentricity refers to the shape of the orbit. The two are independent, as you can change eccentricity without changing inclination, and you can change inclination without changing eccentricity. An inclination manoeuvre simply changes the tilt of the orbit. In practice this often does lead to a minor change of eccentricity, but the point the article is making is that it takes a lot more fuel to change the inclination of an orbit than it does to simply alter the eccentricity.