He has published lucid on-line articles on the physical principles observervable in the collapse of the World Trade Center Towers. In particular, his article WTC7: NIST Admits Free Fall focuses on the significant errors and discrepancies in the National Institute for Standards and Technology official explanation of this third collapse. It is these very errors and discrepancies that form the basis for Chandler’s talk on Day 3 (September 10) of the Hearings.