

Source - Arabian Peninsula & Persian Gulf Database
Visit link for full article
During the recent testing the Shahab-3B proved several significant differences over the basic production variant, with the most important changes being done on its guidance system and the warhead, but few small also on the missile body.
The most significant change is a new re-entry vehicle, with terminal guidance system and a new steering method, completely different from the normal re-entry vehicle with spin stabilization of the Shahab-3A.
The new re-entry vehicle has now place for a rocket-nozzle control system so that no spin stabilization is needed anymore - at least not during all of the flight after the boost phase. Nevertheless, this new nozzle-control system enables the Shahab-3B guidance and steering in all phases of the flight, so that course corrections can be done at any time.