Performance refusal-critical failure speed in C-130 General Posted May 11, 2013 That's an excellent explanation, thanks for that. I wish I'd seen that scissor chart when I was first starting out! My only comment is that this is how I learned this stuff early on (without the chart) and I think we could do better by also explaining that neither acceleration nor deceleration are linear when we talk about more advanced concepts. The relationships don't change, and the chart is 100% valid to explain the relationships, but when used in absence of true curves or explained that way, it doesn't explain everything. In fairness, when we're first learning these concepts, it's probably better to keep it simple, but there still needs to be some explanation that acceleration is not linear. And this skews our understanding of following concepts like accel time checks. To be clear, my point doesn't affect this aspect of TOLD at all, and to address the OP's question, this is probably as far as we need to delve into it. My point about acceleration curves only affects the accel time check which was brought up during the discussion.