The PBS special brought up the point that the airplane's impact disabled all sprinkler systems above the crash.
The program only mentioned the subject of sprinkler systems in a couple of sentences about the first tower struck. It stated since the aircraft impacted the core, the sprinkler system was affected.
The program made the point that the core on the second tower was not directly affected by impact, and there was no mention of the sprinkler system in the second tower struck.
Ironically, in the FEMA report, one of the primary reasons for the collapse was the fact the sprinkler system had been disabled, yet in an hour long program, Nova mentions the sprinkler systems for less than 15 seconds.
No mention of the evidence presented in a Memphis court that days before 9-11 Middle Eastern terrorists, the Hammad cousins, were working on the sprinkler systems at the WTC.
see www.gomemphis.com
search for Hammad articles for the complete picture