Triples combinations have a rearward amplification of _________.

Rearward amplification causes the crack-the-whip effect. Rigs with the least crack-the-whip effect are shown at the top, and those with the most at the bottom. Rearward amplification of 2.0 on the chart means that the rear trailer is twice as likely to turn over as the tractor. You can see that triples have a rearward amplification of 3.5. This means you can roll the last trailer of triples 3.5 times as easily as a 5-axle tractor-semi.