Why does the Harrier jet have four landing gears? I was looking at pictures of Harrier jets and I noticed something.



They have four landing gears. That seems pretty unusual for a fighter jet - most have only 3 in a triangle formation.

What is the reason for this 4 point configuration? It seems to just add complexity and cost without really increasing stability.
The main load bearing landing gear is in a bicycle setup, with 2 outriggers for stability.

This allows the gear to be lighter, stay close to the center and out of the way for the jet blast.

The Lockheed U-2 also has its gear in the bicycle configuration and takes off and taxies with detachable "pogo" outriggers for stability.