HN 39:
I should have used the term near "isosceles" rather than near "equilateral" earlier. (45, 61, 74)
TST: AIR speed parameters (KTAS, KCAS) are sensed by the aircraft onboard systems. You are correct that the aircraft has a trig calculated speed of 151 knots. Your making the assumption that all 151 knots of actual speed would be sensed by the on board systems at a 61 degree AOA. Maybe you're right, I don't know, but the other possibility is that at that AOA (61 degrees) there is some disturbed airflow across the pitot. The pitots are roughly longitudinal. Most "normal" large aircraft flight conditions are flown with the pitots quite a bit less than 60 degrees from the relative airflow.