Ballistic Missiles and the “½ Rule”

May 18, 2017

Real Clear Defense:

North Korea’s ballistic missile tests are indeed a roller-coaster ride. After a string of failures in its recent ballistic missile testing program, with some missiles failing almost immediately after launch, last Sunday it conducted what some are calling its most successful ballistic missile test to date. The test provides a shot in the arm for Pyongyang’s WMD programs. It also signals to the broader international community that the North’s ballistic-missile capabilities are definitely improving. Yes, the missile flew to a range of 787 km—on the face of it, nothing startling. But over at 38North, John Schilling noted that the test represents ‘a level of performance never before seen from a North Korean missile’ and suggested that the missile’s range is better seen as 4,500 km, not 800 km. He’s not making a wild guess.

The test provides an excellent opportunity to remind readers of an important general rule about missile range. The rule can be found in a useful—and free—little publication called The physics of space security: a reference manual. In their chapter on space launches, the authors take the reader through what’s called the ‘½ rule’.

Read the full article.

International Cooperation