More information about the Brazilian rocket tragedy

After two successful test flights there was a long delay in further flights (reason unknown, I'm still looking into it), and since resuming their VLS program there have been two failures in flight requiring destruction of the rocket, and now this accident on the launch pad.

From MASA Planet, a rocketry newsletter:
"...The rocket consists of seven solid propellant stages—three in the core vehicle and four strap-ons—with additional solid motors used for roll control. The first launch attempt was at Brazil's Alcantara site on 2 November 1997, but one of the SRBs failed to ignite.... Although the rocket maintained attitude and an upright trajectory, it eventually deviated from its planned course and the rocket and its SCD satellite payload had to be destroyed. The second launch, on 11 December 1999, was more successful, but the second stage failed to ignite and the rocket and payload, a Brazilian SACI satellite, again had to be destroyed. A third launch attempt may occur in 2003. "

No official word yet on what the cause of the explosion could have been, although speculation is suggesting that the previous ignition problems may have provoked a more rigorous pre-flight test of the igniters. Perhaps too rigorous.