Damage to Basement and Lobby

The best summary of damage witnessed in the lobby and basements after the aircraft impact is written as a discussion in a forum.

The posts by username achimspok provide the damage record in this lively debate.

Some highlights of the discussion are reproduced below:
How do liquid and droplets travel through air?

Since kerosene has a lower density than water I would expect smaller droplets after a 350m fall.

* g: gravity
* cw: ≈ 1, drag coefficient of the droplet
* ρL: density of air (1.2 kg/m³)
* vE: max. fall speed
* r: radius of the droplet
* ρW: density of liquid (825 kg/m³)

So we get for the elevation of floor 95 (pink) and floor 77 (yellow)

3mm drops from the elevation of floor 77 would fall one minute before reaching the lobby.
2mm drops ... 68 sec
1mm drops ... 98 sec
0.5mm drops ... 138 sec
Of course they have to fall straight down otherwise they would need much more time to running down the walls. And we have to consider the upwards speed of the air due to thermal suction.

The impression of falling elevators exploding on impact is hard to imagine if the pause between impact and explosion is at least 60 seconds. Well, impact of what?
A practical example of the dispersal of liquid fuel in air.

Notice how the speed of the liquid droplets slows down extremely when released from the solid projectile.

FAE: Fuel-air explosion in the elvator pits of the towers?

"Fuel-Air Explosives [FAE] disperse an aerosol cloud of fuel which is ignited by an embedded detonator to produce an explosion. The rapidly expanding wave front due to overpressure flattens all objects within close proximity of the epicenter of the aerosol fuel cloud, and produces debilitating damage well beyond the flattened area. The main destructive force of FAE is high overpressure, useful against soft targets such as minefields, armored vehicles, aircraft parked in the open, and bunkers."
http://www.fas.org/man/dod-101/sys/dumb/fae.htm

Elevator shafts to the basements and lobby

Elevator #7 at the 92nd floor. Elevator #6 to the right, elevators 90-92 at the top. It may be a bit hard to see, but the H columns are transitioning to box column further down.

Elevator #7 at the 80th floor. Elevator #6 shaft to the right, elevators 90-92 at the top.

Elevator #7 at the 46th floor. Elevator #6 to the right, express elevators 8-11 to the left.

Express elevator shafts 8-11.

Pit for Elevator #7 and #6. at the AB1 level.

Elevator 50 at the 92nd floor. Elevators 90-92 to the left.

Elevator 50 at the 75th floor. Elevators 72-74 to the left, and elevator 49 to the top.

Elevator 50 at the 47th floor. Elevators 72-74 to the left, and elevator 49 to the top.

Elevator 50 at the 42nd floor. Elevators 45-47 to the left, and elevator 49 to the top.

Elevator 50 at the 3rd floor, above the Plaza level. Elevators 45-47 to the left, and elevator 49 to the top. This is the only elevator that terminates at the AB5 level.

From username Enik from this post

Created on 03/24/2011 09:13 AM by admin
Updated on 06/15/2012 06:25 PM by admin