Pentagon Explosion
Explosion at Pentagon Involved More than Jet Fuel Combustion
The Pentagon attack involved an explosive detonation. This is documented by eyewitness reports of several features of the event that can be explained by powerful explosives, but not by the impact of a jetliner and combustion of its fuel. Those features include:
- A shockwave that was strong enough to knock people off their feet hundreds of feet from the center of the blast
- The odor of cordite, an explosive compound
- A bright silvery flash
Strong Shockwave
Several witnesses described a shockwave that knocked them to the ground, both inside and outside the building. Several described it as a concussion. Such a shockwave cannot be explained by the combustion of jet fuel, and indicates the detonation of an explosive. Explosive detonations produce blast pressures thousands of times stronger than hydrocarbon fireballs because explosives are oxidized by chemicals intrinsic to them whereas hydrocarbons rely on oxygen in ambient air for combustion. Consequently the chemical reaction proceeds at a much higher rate in an explosive.
Hydrocarbon fireballs can produce detonation waves if the fuel and air are mixed prior to ignition, but such detonation waves are comparatively weak. The violence of most plane crashes precludes such pre-mixing. In the Twin Tower jet collisions, the columns of the curtain walls diced the fuel tanks in the wings, assuring fuel and air mixing about as optimally as could be imagined in a collision, and yet there were no reports of detonation shockwaves.
Cordite
Cordite is an explosive compound used in aircraft gun ammunition. Several witnesses with the benefit of military experience recognized the smell of this compound. Cordite N consists of three main explosive compounds: nitroguanidine, nitrocellulose, and nitroglycerin. It is cool-burning, and produces little smoke and no flash, but, like other explosives, produces a strong detonation wave.
Silvery Flash
Several witnesses described seeing a bright or silvery flash. This is also inconsistent with jet fuel combustion, which produces a fireball whose color is at brightest yellow, not white or silver. This flash must have been produced by some means other than a cordite explosion, whose detonation is notably free of a flash.
It is possible that rapid oxidation of metals in the plane such as aluminum and magnesium, wes responsible for the bright color of the flash. The griding of the plane's metal by the high-speed impact, and possible augmentation of the explosion by explosives such as cordite, might have powderized a significant quantity of such metals to generate such fireworks.