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Reading about orbital manoeuvres, I found a few reference to the "Broken Plane Manoeuvre".

One illustration describes it:

Source: http://hopsblog-hop.blogspot.jp/2013/01/deboning-porkchop-plot.html

From what I understand, it is called life this because the burn which appear to instantaneous when scaled towards a sun orbit, appear to be broken.

In that sense, any manoeuvre that include a plane change is a "broken plane".

Any manoeuvre (with sufficient thrust) should appear broken the same way.

Do I understand correctly ? Why do we use the adjective "broken" only for plane (inclination) changes ?

Antzi
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  • I think the name comes from the "broken"/bent image of the combination of orbital planes before and after the manoeuvre, not from the properties of the burn itself. – jkavalik Oct 24 '16 at 13:05

1 Answers1

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The "pure" Hohmann transfer only includes entry and exit burns, and therefore the transfer itself occurs entirely in one plane. As an earlier diagram in your linked article shows, this requires nearly 90 degree plane changes at entry and exit, which is absurdly inefficient. For small inclination changes it is much more efficient to do a midcourse plane change, which breaks the plane of the Hohmann transfer.

In practice, nearly any interplanetary transfer in our solar system will likely include a plane change like this, unless the position of the bodies aligns with the ascending and descending nodes between the planes.

Russell Borogove
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