More information has recently become available on the “Unexpected Energetic Event” that was apparently responsible for the failure of the first SM-3 Block IB intercept attempt (FTM-16) in September 2011.  The cause was a failure in the SM-3 interceptor’s third rocket stage motor.    Despite assurances that this component, which is common to both the IA and IB variants of the SM-3 interceptor, had performed successfully many times previously, it also apparently experienced an “anomaly” in its previous test (FTM-15, April 14, 2011, of an SM-3 IA) serious enough to temporarily halt deliveries of new interceptors.  In the most recent test, a May 2012 repeat of September’s failed intercept, the part of the third stage booster (the second pulse) that had failed previously was not used, and the interceptor hit its target.

 “Unexpected Energetic Event” during the FTM-16 intercept test, September 1, 2011.[1]

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X-Band Radar Transmit/Receive (T/R) Modules

In order to estimate the capabilities of missile defense radars such as the AN/TPY-2s used both as Forward Based X-Band (FBX) radars and THAAD theater missile defense battery radars it is necessary to assess the power output of the radars.  There do not appear to be any public official numbers for the peak or average powers of these radars.  However, one can estimate these based on the peak and average powers of transmit/receive modules making up their antennas.  This post discusses and assesses these power outputs for the TPY-2 and other X-band missile defense radars (SBX, GBR-P).  In particular, it argues that the average power outputs of the modules are 6, 10 and 16 watts for the GBR-P, SBX, and TPY-2 radars respectively

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