Before we look at the performance of the Tigra, we are going to compare the progress of the car that came through the same shot in the footage ahead of it (see Fig. 60). This will give us an idea about what a car would regularly do through that stretch of road, and it can also help us to identify any figures we arrive at for the Tigra as plausible or not. While we are going to eventually use the numbers generated by the slightly more complex maths, initially we will work with average speeds. These are not satisfactory because they only show what the average speed across a distance is, rather than what a speed is at a certain point.
So according to the author’s calculations (which can be seen in Appendix A) the preceding car came through the lights and crossed the junction at an average speed of 30mph. However, at point C, the speed across the distance from the junction exit had reduced dramatically – just under 20mph. This is a great reminder that Artillery Place, from the junction, runs up the side of a hill. Any driver, let alone any physicist, will know that a reversal of velocity occurs once a car gets on a hill due to the inclination to roll backwards, and there is a loss of forward speed. At this stage, the accelerator needs to be engaged to counter the deceleration.
Therefore, what we need to realise is that any car that goes up Artillery Place needs to accelerate up it as a matter of course. In fact, the lead car must be accelerating all the way up the hill to reach and maintain an approximate speed of 31mph. When he gets much nearer the top, at point G, his acceleration has been converted into a speed increase and he moves onto the hill top at about 34mph. The lead car, then, has had a need to accelerate to return to its initial speed. This reminds us that in this system, any applied acceleration does not automatically produce high velocity. On the contrary, a normal journey up the hill, where the driver must have been accelerating (although we do not know at what rate, of course), has only produced a small increase in speed across the system.
What we need to remember, then is when the witnesses talk about being aware of acceleration, this doesn’t mean that they are aware of speed. Both John Power and Amanda Bailey may have been aware of some indication of acceleration – like the noise of the engine of the Tigra, or the way it moved relatively to John Power’s car – but not one of the witnesses were able to satisfactorily able to describe the speed. This is a most surprising omission when it comes from John Power – he was following the Tigra, of course, and should have been able to understand his own speed through his dashboard. He should have understood the Tigra’s relative speed. It’s incredibly important that he only talks vaguely about acceleration rather than giving even an estimated number regarding speed and miles per hour.
So at last we get to the findings regarding the Tigra. From the results produced by the preceding car, it seems that we have reasonably good measurements for the distances, and have been able to time the progress of the vehicles quite satisfactorily. The first thing we must notice about the Tigra in comparison, is that it travelled extremely slowly over the junction: between points A and B it was travelling at a bit more than 16mph – we think the actual speed at B was under 17mph. Obviously, if the preceding car tells us what is normal, the behaviour of the Tigra, travelling at nearly half the speed, was definitely abnormal. Between B and C, (C is s where it began to swerve across the reservation, approximately), the Tigra was travelling at an average speed of 20mph – the actual speed at C was calculated at 22mph. This measly figure was the sum output of all that famous acceleration. Between C and D the car travelled at an average 24mph, the actual speed at D was 25mph, which is the position of the Tigra as it is imaged poised to strike Rigby. It should be noted that our more complicated calculations which involve knowing about acceleration bear a good similarity to the simple averages.
Now we get to point E, but the public didn’t see the Tigra travel this section from D. We can’t do an average speed, but that doesn’t matter. We can work out the speed based on an assumption of whether the vehicle was accelerating full pelt, or decelerating due to gravity (which wouldn’t require braking, and would be easier to conceal). So, continuing, if the car then decelerated before it hit Rigby – and it could be argued that the very reason we didn’t see the film was so that proof of deceleration couldn’t be disseminated to people who would do these calculations – at E the Tigra was travelling at an actual speed of just under 24mph. Even if we think that the Tigra continued to accelerate to this point – so that it would be travelling at 27 mph – it still would not be travelling as fast as the preceding car did. Therefore, the Tigra is at this stage going slower than what a normal vehicle would do if it was doing nothing special in its movement through the scene. It is fairly clear that because the Tigra was so incredibly slow before it reached the hill, it had to produce a higher rate of acceleration to reach a comparable speed with the preceding car at point E. So, what we can say is that a great show of acceleration – in which a terrible noise must have been generated – resulted in a below normal performance. It is a mystery quite how Lee Rigby “didn’t seem to mind the car or notice at all” according to Amanda Bailey. However, we can say that the promotion of the idea of acceleration through the witnesses had no connection with the speed that was claimed for the Tigra – i.e. 30-40mph. The Tigra was literally blowing smoke.
As was concluded in Chapter Thirteen, the Tigra definitely started to decelerate just before or just after it had hit Rigby, and then it continued to decelerate. The author’s findings suggest that the Tigra could very well have been travelling at 21mph when it came to position G – or when it was supposed to have hit the stanchion. If it accelerated into Rigby before decelerating, then it would have hit the stanchion at 25mph. Even if we decided that the Tigra accelerated all the way up the hill, it would not have been doing more than 30mph when it hit the stanchion – which means that in all possible cases, the prosecution’s figure of 30-40mph is completely outside, and by a long way, the window of real possibilities. And then the reader must remember that we are presuming that the Tigra is going at what we think its top rate of acceleration – and that the driver never touches the brakes. The reality could be that the Tigra arrives at the stanchion very slowly indeed. However, we’re going to presume, still, that Adebolajo wants to kill Lee Rigby, so the above mentioned figures are the fastest he could have been doing in order to try and accomplish it.
The “unknown” of speed is solved, and so are all of them. Before we go on to try and address the 8 points raised in Chapter Ten, we need to state a finding regarding the conduct of the trial in relation to this issue of speed. Given that there is no apparent valid source for the supposed speed at which the Tigra struck Rigby, we can accuse the prosecution of pulling it out of thin air, and at a suitably overstated figure that would fix an association between speeding beyond limits and catastrophic injury to pedestrians. If the prosecution had offered a lower speed – something that would be nearer a real figure – the association would not have been fastened in the minds of the jury. On the other hand, a lower figure would not necessarily have explained the injuries supposedly sustained by Rigby. So the figure was invented for maximum possible effect, and to make the narrative feasible. If the defence teams had challenged this figure, it would not have stood. This begs the question, when the data was so fragile in supporting the prosecution’s case, why didn’t the defence teams challenge it? We also need to question whether or not we can trust witness testimony that was obviously crafted to obfuscate so that we are hearing about ineffectual acceleration rather than speed. Even Miah’s ‘force’ is derived from a relationship between mass and acceleration. The question we need to ask is this: were the witnesses in any way directed to state their experience so as to corroborate the invented speed of the Tigra?