It is believed that 1,344 people were on or above floor 92 of WTC 1 when Flight 11 directly impacted floors 93 to 99, and all died. Some 600 people were on or above floor 77 (adjacent to a Skylobby floor) of WTC 2 when Flight 175 struck floors 77 to 85, of whom 18 escaped. Twelve of the people who escaped were among up to 200 people in the Skylobby. In interviews with 271 survivors, researchers in 2008 found that only about 8.6% had fled as soon as the alarm was raised while about 91.4% stayed behind to wait for more information or carrying out at least one additional task (collecting belongings/calling a family member). The interviews also showed that 82% of those who were evacuating stopped at least once during their way down, due to congestion on the stairs, to take a rest, or due to environmental conditions (smoke/debris/fire/water). Communication breakdowns also hampered the evacuation of workers as one survivor recounted calling 911 multiple times from the South Tower only to be put on hold twice, as 911 operators had a lack of awareness about what was happening and were overwhelmed with the amount of calls, at times repeating incorrect information. Communication issues were also seen as first responders were utilizing different radio channels to communicate, their frequencies were overwhelmed or they had been off duty and responded without their radios. North Tower In the moments after Flight 11 struck the North Tower, the roughly 8,000 people who were not trapped by the impact (everyone from Floor 91 downwards) were faced with a harrowing scenario. The towers of the World Trade Center complex had not been designed to facilitate a mass evacuation of everybody in the buildings, and in each tower there were only three stairwells descending to the ground level. Another hindrance to the evacuation of the World Trade Center was that as the planes struck, the force of the impact caused the buildings to shift enough to jam doors in their frames, and stairwells became blocked by broken wall boards, trapping dozens of people throughout the building, mostly on the floors closer to the impact zone. For those that were above the point of impact, all were trapped, with one victim relaying to 911 after the first plane hit that the stairs were inaccessible for the 106th floor. At least 77 people were freed on the