A SOFTWARE glitch has left the Pentagon wondering what really happened in the
missile defence test two weeks ago, in which a missile shot down a dummy warhead
(New Scientist, 21 July, p 12).
The glitch affected the sophisticated new radar system built on Kjawalein
Atoll in the Marshall Islands, the spot where the interceptor missile was
launched. The radar identified and tracked the dummy warhead, which was launched
from California, and guided the interceptor. However, the radar couldn鈥檛 assess
what happened after the impact.
The radar was primarily designed to guide the interceptor, but it could also
be reconfigured to focus on the debris. 鈥淲e wanted to see if we could use it for
hit assessment,鈥� says Rick Lehner of the Ballistic Missile Defense Organization.
Advertisement
It was supposed to switch automatically into a different operating mode at
the point of impact, so it could monitor the expanding cloud of debris.
Raytheon, the company that built the radar, believes something went wrong with
the software that was supposed to make the switch.
The radar did, however, record the raw, unprocessed radar signal, which is
now being analysed by Lehner and his team. So far, he says, 鈥淓verything else
seems to have worked as designed.鈥�
The failure may be significant if it shows the radar can鈥檛 deal with clutter,
such as strips of foil called 鈥渃haff鈥� released to confuse the radar, says Bob
Sherman of the Washington DC-based Federation of American Scientists. However,
he cautions, 鈥淲e don鈥檛 know that yet.鈥�