Night Fall

I looked at the fuel tank. I had imagined something the size of a truck’s fuel tank, but this thing was as big as a garage.

Mr. Siben continued, “The pieces of the original fuel tank that were recovered were taken to a laboratory where they were studiedintensely.”He looked at meintensely and went on, “First, there was absolutely no chemical evidence found of explosive residue other than fuel-air. Follow?”

I repeated dutifully, “There was absolutely no chemical evidence found of explosive residue other than fuel-air.”

“Correct. Second, there was no evidence on the fuel tank’s metal of a high-velocity explosion-no pitting, no sign of what we call torturing or feathering on the metal. Follow?”

“There was no evidence-”

“Third, there was no evidence on the fuel tank of missile penetration-no entry or exit hole, which we call petaling-like a flower petal-which rules out a non-explosive warhead-a kinetic missile.” He looked at me and said, “I understand that you believe a kinetic missile was involved.”

I hadn’t evenheard of a kinetic missile before I spoke to Captain Spruck, but Kate had written tonight’s script before I even knew I had a part in the play. I asked Mr. Siben, “Where’s the original fuel tank now?”

“In storage at the laboratory in Virginia.”

“What percentage of it was recovered?”

He looked at me and replied, “About ninety percent.”

“Is it possible, Mr. Siben, that there could be an entry and exit hole in the ten percent you haven’t recovered?”

“What are the chances of that?”

“Ten percent.”

“Actually and statistically, the chances of two distinct holes, entry and exit, opposite one another, both not appearing in the ninety percent of the reconstructed fuel tank, are far less than ten percent.”

“Okay, one percent. That still leaves it an open possibility.”

“Not in my mind. All right, we also looked for matching entry and exit holes in the fuselage…” He nodded toward the reassembled aircraft. “… and we found no distinctive holes with inward or outward metal petaling.”

I replied, “Obviously, the most critical parts of this aircraft are missing-the part where the explosion occurred.”

“It’s not all missing. Inside this fuselage, which you can see later if you wish, is the reconstructed interior. The flooring, carpeting, seats, overhead bins, the ceiling, lavatories, galleys, and the rest of it. You can’t tell me that a kinetic missile passed through the center section of this aircraft and did not leave one trace of its entry or exit.”

Mr. Siben was probably right, of course. So, here we had the classic case of the unimpeachable eyewitness-Captain Spruck-and the unimpeachable forensic evidence, represented by Mr. Siben. The evidence was totally contradictory, and to be honest, I was leaning toward Sidney Siben.

I glanced at Kate, who seemed pensive, or perhaps conflicted herself. Obviously, she’d been through this a hundred times, and for some reason she leaned, privately, toward the kinetic missile theory.

I tried to recall what I knew of the forensic evidence, and what Spruck had said, and I asked, “How about the air-conditioning units near the center fuel tank?”

“What about them?”

“Well, where are they?”

He pointed to the right of the center fuel tank. “There. Reconstructed.”

“And?”

“No evidence of high-explosive residue, no sign of a kinetic missile penetration. Do you want to look at them?”

“How much is missing?”

“Again, about ten percent.”

“Well, Mr. Siben, what’s missing might hold an important clue. And if I were a conspiracy theorist, I might say that something was actually found and spirited away.”

He looked a

I replied, “Yet, if this was a murder investigation, a medical examiner would be reluctant to rule this an accident and to rule out a crime.”

“Is that so?”

“Yeah, it’s so.”

“What would you need?”

“I’d need to knowwhy you think it was an accident and not a crime. The lack of evidence for a crime doesn’t prove it was an accident. Do you have proof it was an accident?”

“Noproof other than the fact that this explosion occurred where an accidental explosion is most likely to occur-in an empty center fuel tank, filled with volatile vapors. If you like analogies, imagine a house that burns down. Arson or accident? Arson is rare, accidents happen all the time. The fire marshal determines very quickly that the fire started in the basement. He goes right to the mechanical room where most fires start-furnace, air-conditioning unit, electrical panel, or stored flammables. He’s not looking for a Molotov cocktail thrown through a window. His investigation focuses on the most likely cause, based on appearances, on his years of experience, and on the overwhelming odds that accidents happen where and how accidents usually happen.”

He looked at me as though I might need another analogy, which I didn’t, but I had one of my own. “The safe neighborhood has changed, Mr. Siben. It’s now a dangerous neighborhood, and Molotov cocktails thrown through windows are not out of the question anymore.”

“You,” he said, “as a criminal investigator, look for and expect to find a crime. I, as a safety engineer, look for and expect to find-and have always found-a safety issue or pilot error as a cause to an aircraft accident. I am not unaware of the possibility of foul play. But there were hundreds of criminal investigators on this case, and not one of them found any concrete forensic or even circumstantial evidence of any crime-not an enemy missile attack, not a friendly fire missile, and not a bomb on board. So, why do people still believe it was anything but an accident? And who could be covering up something sinister? And why? That’s what I don’t understand.”

“Me, neither.” In fact, in criminal investigations you always have to ask why. If it was a terrorist attack, we knew why-they don’t like us. But why would the government want to cover up a terrorist attack?

If, on the other hand, it was a friendly fire accident, I could see why the guys who accidentally launched a missile at an American airliner would want to cover it up. But, as Captain Spruck said, virtually no one in the chain of command or the government would or could go along with a cover-up of that magnitude.

Kate, who had stayed silent for some time, said to Mr. Siben, “John seems to want to know how the center fuel tank could have accidentally exploded.”

Mr. Siben nodded and looked at the aircraft, then at the lime-colored tank and said to me, “First, you start with the nearly empty center fuel tank, which has only about fifty gallons of fuel left sloshing around the bottom that the scavenge pump can’t get to. Then you have these volatile vapors in that tank-”

“Excuse me. Why was the fuel tank empty?”

“Because the flight didn’t need the extra fuel. Wing tanks are filled first and the center tank only if needed. This flight to Paris had a light passenger and cargo load, and the forecast was for good weather and tailwinds.” He added, “Ironically, if the passenger and cargo load had been heavier, and/or there had been bad weather or headwinds, that tank would have been full of jet A fuel, which is actually difficult to ignite. Fuelvapors are volatile. So that fact alone fit the scenario of an electrical short circuit igniting the vapors and causing the kind of explosion that the forensic evidence strongly suggests.”