floor. [ 57 ] [ 83 ] As they hovered above the target, however, the first helicopter experienced a hazardous airflow condition known as a vortex ring state . This was aggravated by higher than expected air temperature ("a so-called 'hot and high' environment" [ 57 ] [ 76 ] ) and the high compound walls, which stopped the rotor downwash from diffusing. [ 76 ] [ 84 ] [ 85 ] The helicopter's tail grazed one of the compound's walls, [ 69 ] damaging its tail rotor , [ 86 ] and the helicopter rolled onto its side. [ 23 ] The pilot quickly buried the aircraft's nose to keep it from tipping over. [ 72 ] None of the SEALs, crew and pilots on the helicopter were seriously injured in the soft crash landing, which ended with it pitched at a 45-degree angle resting against the wall. [ 57 ] The other helicopter landed outside the compound and the SEALs scaled the walls to get inside. [ 87 ] The SEALs advanced into the house, breaching walls and doors with explosives. [ 72 ] Bin Laden killed The SEALs encountered the residents in the compound's guest house, in the main building on the first floor where two adult males lived, and on the second and third floors where Bin Laden lived with his family. The second and third floors were the last section of the compound to be cleared. [ 88 ] There were reportedly "small knots of