Seems a Boeing 757 enroute in the US recently responded to a resolution advisory, and 2 passengers were injured. One seriously.
Reaction to Resolution Advisories is a subject I fairly frequently address in the simulator after a check. Though I believe the sim motion cues are useful, they can’t reproduce G-forces. Sometimes a crew overreacts, but the sim doesn’t give the physical feedback that would discourage this.
So I break out Eurocontrol’s ACAS guide, which provides the following guidance.
“An acceleration of approximately ¼ g will be achieved if the change in pitch attitude corresponding to a change in vertical speed of 1 500 ft/min is accomplished in approximately 5 seconds, and of ⅓g if the change is accomplished in approximately three seconds. The change in pitch attitude required to establish a rate of climb or descent of 1 500 ft/min from level flight will be approximately 6° when the true airspeed (TAS) is 150 kt, 4° at 250 kt, and 2° at 500 kt. (These angles are derived from the formula: 1 000 divided by TAS.)”.
I point out how small the required pitch changes are.
(And sometimes that knowing good ole’ Attitude + Thrust combinations to get where you wanna be are still a useful way to fly an airplane).
TCAS phraseology is also a point that bears emphasizing in training.