by Don Brown
Again, the position at capital “C” (ground zero) marks the position on the ground just below Extortion 17 the moment it was struck by the RPG.
The small “a” and the small “b” are the “legs” of the triangle, and the small “a” represents the distance between the helicopter at the point of impact and the ground, which the Combat Assessment Team determined to be between 100 and 150 feet (Exhibit 60, page 6).
All triangles have 180 degrees total. In this triangle, the interior angle at Point “C”—ground level under Extortion 17 (ground zero), is 90 degrees (a right angle).
That leaves a total of 90 degrees to work with using the remaining interior angles, which are the key to determining the length of leg “b” (distance from shooter to ground zero) and the hypotenuse “c” (distance from shooter to blade of helicopter).
In the diagram provided at page 14 of Exhibit 60, it appears that the interior angles at “A” (position of shooter) and “B” (point of impact) are each about 45 degrees.
Actually, that’s not far off. On page 28 of exhibit 60, the interior angle at the point of impact “B” was given as approximately 50 degrees. The report showed that the “(S) Weapon angle of impact was approximately 40˚ relative to the bottom surface of the blade” [author’s emphasis].
In other words, from the bottom surface of the blade to the line of attack by the RPG (the hypotenuse of the triangle), there was an angle of 40 degrees.
Now the blade, which was spinning horizontally, and the line down to ground zero intersect and form a right triangle of 90 degrees, mirroring the right triangle at ground zero (point “C”).
Let’s look at our triangle again.
So to review, the interior angle at “B” (point of impact) is 50 degrees. The interior angle at C (ground zero) is 90 degrees, because it’s a right angle. The interior angle at A (position of shooter) is by deduction 40 degrees, because we’ve already used up 140 degrees (90 at ground zero plus 50 at point of impact) leaving only 40 degrees.
With the length of “a” and the interior angle of “B” (50 degrees), the distance from the shooter to the chopper can be computed using the basic trigonometric principles of sine, cosine, and tangent.
The tangent of 50 degrees is 1.19. Remember that the known height “a” from ground zero (Point C) to the point of impact (Point B) is 100 feet.
To determine distance from ground zero to the shooter (line “b”), multiply 1.19 by 100 (length of “a”). 100 x 1.19 = 119 feet.
So now we know that the shooter was lurking only 119 feet from ground zero, at the time he fired the RPG that brought the chopper down.
Stop and consider this for a moment. Remember that the blades on that chopper were 120 feet all the way across, so that means they extended 60 feet out from the axis.
The shooter, assuming Extortion 17 was at a height 100 feet above ground, was on the ground 119 feet away from ground zero. But the choppers’ blades extend 60 feet each way out from the spinning axis being driven by the rear engine. That means that the shooter was so close to the chopper’s flight path that he could have been as close as 59 feet to being directly under the rotation of the blade!
That math is easy to calculate. 119 feet distance, shooter to ground zero minus 60-foot radius of the blade, leaves you with 59 feet. That’s how close the shooter was to being almost directly under the chopper as it landed.
On August 10, 2011, four days after the shoot-down, the UK Daily Mail quoted an Afghan governmental official as saying that the Taliban was tipped off as to the mission, that the Taliban knew the flight path, and that the chopper was lured to the landing zone.
He (an Afghan government official) said that Taliban commander Qari Tahir lured US forces to the scene by tipping them off that a Taliban meeting was taking place.
He also said four Pakistanis helped Tahir carry out the strike.
“Now it’s confirmed that the helicopter was shot down and it was a trap that was set by a Taliban commander,” said the official, citing intelligence gathered from the area.
That same report, that the Taliban had knowledge of the flight of Extortion 17, followed in one of the other major British dailies, the UK Telegraph.
Bear in mind this is not the Taliban crowing. It’s the British press quoting the Afghan government.
If the chopper were lured in by baited information on Tahir’s location, that would explain how the Taliban got off such a point-blank shot. And the math above shows that the shot was about as point-blank as you can get, which proves that (a) the Daily Mail report that the Taliban was tipped off on Extortion 17’s flight plan from the inside was probably correct, and (b) that the position in General Colt’s Executive Summary later adopted by the Defense Department, that the RPG was fired from a tower 220 meters (720 feet) away, is mathematically impossible.
Now moving on in our calculations, there’s still one number missing, and that’s the length of the hypotenuse, or “c,” which will show the actual distance between the shooter and the helicopter. Remember that General Colt claimed 220 meters or 720 feet (beyond the effective range of the RPG).
But now apply the Pythagorean theorem, a2 + b2 = c2, to get an idea of just what a point-blank shot this was.
The small “a” is the distance from the helicopter blade to ground zero. Using 100 feet, because the JCAT estimated between 100 and 150 feet above the ground at the moment of attack, a² is 100 times 100 or 10,000.
Now the small “b” is the distance from the ground (directly under the helicopter) where the terrorist fired the RPG. Based upon the earlier calculations using the tangent of 50 degrees, this distance is 119 feet.
Therefore, since b is 119 feet, b² is 14,161.
Now adding a² (10,000) plus b² (14,161) yields c² (24,161).
To get the estimated distance of line c, the hypotenuse of the triangle, take the square root of 24,161. The square root of 24,161 is about 155!
Therefore, if Extortion 17 were 100 feet off the ground, given the approximate angle as diagrammed by the JCAT team, the Taliban insurgent was probably about 155 feet (51 yards) away when he fired.
Remember, General Colt claimed the distance at 220 meters or 720 feet. But the math, assuming 100 feet off the ground as determined in the JCAT report, shows a distance of one-fifth that at 155 feet. The figure in the Executive Summary was a gross exaggeration.
Calculation with Chopper 150 Feet Above Ground When Struck
Assuming the chopper was 150 feet off the ground, the other end of the range, applying the same tangent and applying the Pythagorean theorem, the ground distance between the shooter and ground zero is 178 feet, and the actual distance, along the hypotenuse, is 227 feet.
That means the maximum distance that the shooter could have been from Extortion was 178 feet, not 720 feet as Brigadier Colt suggested.
Again, the gross exaggeration of distance-to-shooter is important to supporting the “we did nothing wrong” narrative, which in fact may have a larger purpose, not only to defend foolish rules of engagement, but also to hide the truth about Taliban infiltration of this mission.
So these calculations show an approximate range of distance-to-shooter between 155 feet (51 yards), if the chopper were 100 feet off the ground, to 227 feet (75 yards), if the chopper were 150 feet off the ground.
Just as significant is the shooter’s even closer distance to ground zero. The math showed that the shooter was only 119 feet to ground zero (assuming the chopper was 100 feet off the ground) to 178 to ground zero (assuming the chopper was 150 feet off the ground).
This super-close distance will become more relevant in later discussions of the military’s failure to clear out the landing zone with pre-assault fire, something it easily could have done.
What would be the chances that Extortion 17 would just happen to fly within 75 yards of a Taliban insurgent waiting
with an RPG, unless the Taliban insurgent knew in advance exactly where Extortion 17 was going to land?
About as likely as finding a needle in a haystack.
Clearly, the Taliban shooter was waiting at or near the landing zone, most likely tipped off by someone who knew Extortion 17’s flight path, as the UK Daily Mail reported.
Remember also that it’s mathematically impossible that the shot could have come from some building 220 meters away, not only because the math doesn’t add up, but because the military’s own JCAT (Exhibit 60, page 37) report shows that the maximum effective range of the RPG is 170 meters. Also even if the insurgent had night vision goggles, the range on those goggles is limited. In fact, under the limited lighting circumstances that night, and given that the chopper was operating with its lights off, it would be virtually impossible for him to have seen Extortion 17 from 220 meters (720) feet away, let alone get off an accurate shot with an RPG already out of range.
Chapter 30
Testimony of Apache Pilots and Pitch-Black Conditions
The testimony of the two Apache gunships accompanying Extortion 17 underscored just how dark conditions were at the time of shoot-down, and how difficult it was even for US helicopters with night vision goggles to keep track of Extortion 17.
In examining this interchange between the Apache pilots, it’s important to understand that the Apache call signs were Pitch Black 65 (Gun 1), and Pitch Black 70 (Gun 2). PB65FS is the Front Seat Pilot in the Apache referred to as Gun 1. PB65FS is the acronym for “Pitch Black 65 Front Seat.” PB65BS is the Back Seat Pilot in the Apache referred to as Gun 1. PB65BS is the acronym for “Pitch Black 65 Back Seat.”
The first testimonial exchange, at page 34 of Exhibit 53, was between the co-pilot of Gun 2, call sign Pitch Black 70, about the dark conditions:
BG COLT: Right. What was 17’s light configuration when he came inbound?
PB70FS: He was dark. He was really hard to see. I think they would have the pink light on in the Chinooks or something like that. And they would have their IR strobes on bright. So they were always easy to pick up.
Well, (Extortion 17) doesn’t fly around like that. They were actually—they were real hard for us to find.
More testimony is presented at page 53 of Exhibit 53, this time from the co-pilot of Gun 1, call sign Pitch Black 65 [author’s emphasis].
PB65FS: Where the point of impact was, Juy Zarrin [an Afghan village] was directly to the north. And, yes, that could have silhouetted them. We were literally under goggles. It was red alone. We were having a hard time seeing them due to the fact it was dark and they were dark.
A third exchange appears at pages 54-55 of Exhibit 53, this time from the lead of Gun 1, call sign Pitch Black 65 [author’s emphasis].
PB65BS: Based on where it was, there might have been enough light to silhouette the helicopter to give whoever the shooter was a better idea of the area to aim at. But at least unaided, it never appeared that there was a significant light source of any kind that would silhouette a perfect shape of an aircraft.
Note the consistent theme: Extortion 17 was blacked out to the point that even the American pilots accompanying them, wearing night vision goggles, were having a difficult time seeing the aircraft.
How could some Taliban insurgent, way off at a distance of 220 meters, see the helicopter well enough to aim a RPG launcher at it, fire, and have that RPG strike at a distance beyond its maximum effective range?
The Line of Sight Problem
The aerial photograph on page 174 shows the terrain between the point of attack and the alleged origin of the shot to be full of trees.
There was a field of trees between the “qualat,” the building from which General Colt claims the shot was fired, and the shoot-down point. Additionally, there was a line of trees along the “wadi,” beyond the tree line, separating the low-flying chopper from Colt’s proposed position for the origin of shots. So there was zero visibility, and there was a field of trees in between the shooter and the chopper, which was only 100 to 150 feet off the ground.
The trees in the field were not extremely tall trees, but they were tall enough to provide not only an additional visual obstruction, especially under pitch-black conditions, but also to make it impossible for the RPG to have come in and struck the blade at a 50-degree angle.
The photograph on page 175 is found at page 21 of the Exhibit 60, and was taken later in the day following the shoot-down. If the RPG had been fired from where Brigadier General Colt claims, some 722 feet beyond this tree line, then the grenade would have cleared the tops of these trees, then would have had to strike the chopper at a 50-degree angle, which as noted earlier is mathematically impossible given an above-ground altitude of 100 to 150 feet.
Remember, the chopper was 100 to 150 feet above the ground. These trees were not that tall. But they were much taller than a man, and therefore, were tall enough to create an additional visual obstruction for the shooter standing 722 feet away, and create an additional aiming obstruction, even if the conditions were not pitch-black outside.
It’s not like the shooter, under the Colt claim, would have been aiming across the wide-open space of a desert, or across flat, open water with no obstruction. There were plenty of visual obstructions.
To get a better idea of the obstruction that the trees created, imagine for a moment that you’re looking through these trees, out in the other direction, in pitch-black darkness, trying to see a helicopter about 720 feet (two-and-a-half football fields) away, flying from left to right, only 100 feet off the ground.
It would be impossible to see that chopper, or even aim at it, given the distance, the obstructions, and the dark conditions, even with a weapon that would effectively shoot that far.
Remember, here again is the diagram of the angle of attack, taken straight out of the military’s JCAT report.
Again, it’s plain from this angle, even without doing the mathematica
l calculations, that the RPG could never have cleared the trees, and especially not if the chopper is only 100 to 150 feet off the ground.
Now to recap the evidence proving that General Colt’s distance-to-shooter claim of “220 meters from a building” was clearly false. First, the effective range of the RPG, per the JCAT report (Exhibit 60) was only 170 meters. So the RPG was not in range of the chopper at 220 meters, even if the Taliban had been able to see the chopper and get a shot off from that distance.
Second, light conditions were pitch-black, so dark, in fact, that not even the US pilots in the Apache helicopters accompanying Extortion 17 could easily see it, even with sophisticated night vision goggles.
Third, the principles of mathematics work against Colt’s claim. Flying at 100 to 150 feet above the ground, with the RPG striking its blade from a 50-degree angle, approximate range of distance-to-shooter along the hypotenuse of that triangle ranges from 155 feet (51 yards), if the chopper were 100 feet off the ground, to 227 feet (75 yards), if the chopper were 150 feet off the ground.
Just as significant is the shooter’s even closer distance to ground zero. The math showed that the shooter was only 119 feet to ground zero (with the chopper 100 feet off the ground) to 178 feet to ground zero (with the chopper 150 feet off the ground).
Fourth, trees on the ground and along the wadi, located between the “building” from which Colt claims the RPG was fired and the helicopter, would have made the chopper even more difficult to see from 220 meters, and a straight line-of-fire even more difficult to attain at 220 meters (720 feet).
Fifth, the JCAT report, after assessing all the data on the issue, concluded, “Point of origin was never positively identified or actioned” (Exhibit 60, page 42). In fact, the JCAT report, on the very same page, also concluded that “Participating aircrews were not aware EX 17 was being fired upon until it was hit.”
All of
this undercuts Colt’s claim that the RPG was fired from 220 meters away. That dubious claim was being made, most likely, to try and deflect criticism against the military and the Obama Administration for the foolish rules of engagement that prevented pre-assault fire that could have saved Extortion 17.
This leads to the question—where was the RPG fired from?
Given the tight angle, probably along the tree-lined banks of the wadi. Under pitch-black conditions, the Taliban would have to have been that close to get off a point-blank shot, and the math suggests that they were in fact that close.
Chapter 31
Extortion 17 and the Earlier Ranger Mission
After reviewing Extortion 17’s odd and repeated delays, the sparkle vs. burn confusion, and its apparent stall in the air, one thing seems clear: the helicopter’s odd behavior does not add up.
Isn’t it interesting that just prior to its shoot-down, Extortion 17 was the only aircraft in the sky over the Tangi Valley that could not locate the landing zone? The Apache helicopter gunships knew exactly where the landing zone was. The AC-130 fixed-wing gunship circling 7,000 feet overhead knew exactly where it was.
Of course those other aircraft knew where the landing zone was. In an age of guided-precision GPS that allows smart bombs to find their targets with absolute accuracy and precision when launched from a thousand miles away, landing on the eye of a needle, it is impossible to envision a realistic scenario under which Extortion 17 should have had difficulty finding the landing zone.
