9/11 Explosion according to NIST: WTC South Tower 9:37 am

“The video shot from the WTC plaza captured an intriguing event at 9:37:04 a.m. A jet of air, dust, and a large piece of debris was ejected from a window, 77-355, on the 77th floor at an extremely high velocity. Longer distance videos show that puffs of smoke and or dust appeared simultaneously on the east face from several open windows near the center of the 78th floor and from open windows on the north side of the 79th floor.“ - Page 50/268 in NIST NCSTAR1-5A Ch 9 Appx C. Their theory of why it happened i