Same Intercept Altitude and Geometry

All of the tests have been arranged to have the kill vehicle intercept the mock warhead at the same altitude-230 kilometers. In addition, the geometry of the intercept has been the same in all these tests; that is, the relative direction of the trajectories of the kill vehicle and mock warhead have been the same, and the kill vehicle has approached the mock warhead from behind as both are on downward trajectories toward the earth.

Both the low intercept altitude and the geometry of the trajectories at intercept were apparently chosen to minimize the spread of debris on the ground and in space.

However, an operational system should be able to intercept at a range of different altitudes, and each intercept altitude and location would lead to a different intercept geometry.

As an example of an intercept at higher altitudes, Dr. John Peller, then National Missile Defense Program Manager at Boeing, the prime contractor for the system, described a simulated intercept of a missile launched by North Korea toward Alaska in testimony to the Subcommittee on Strategic Forces of the Senate Armed Services Committee on 24 February 1999. This intercept would occur at an altitude above 1,000 kilometers.