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Using Big Numbers
by Tom Clements
Years ago, I was conducting recurrent King Air 200 training with the two experienced and professional pilots of a Midwest corporation. As part of their takeoff briefing, they used the phrase, “We’ll use big numbers.”
“What did you say?” I asked. “What does that mean?”
Their explanation made a lot of sense to me then, as it does now. It is a procedure that I have adopted and use regularly. I believe it adds a degree of safety that helps to stack the deck in our favor. With one very minor exception – that I will address later in this article – I can see no detriment or downside to it whatsoever. Let me explain.
Not all King Air models have differing takeoff speed numbers depending on conditions. The fine E90 model, for example, bases all of its takeoff data on using a rotate speed of 95 KIAS (knots indicated airspeed) and a 50- foot speed of 100 KIAS. Although Beech does not use the terms V1 and V2 for the E90 – reflecting its date of certification, its weight and the rules that then applied – those two numbers would be the 95 and 100. These speeds apply to all airport elevations, all outside air
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temperatures and all weights. I appreciate the simplicity they provide. Although they may not be “perfect” for all situations, the E90 is such a fine performer that it does very well using them in all situations.
As the King Air history evolved and the larger and heavier model 200 appeared – with first deliveries in 1974 – takeoff numbers became more elaborate. Although I have written and spoken about my disagreement with Beech’s choice of V1/VR for the 200, I have no problem whatsoever with their V2 choices. V2 varies from a low of 99 KIAS – while using approach flaps for takeoff at a light weight of 9,000 pounds – to a high of 121 KIAS – clean, at the maximum gross weight figure of 12,500 pounds. Similarly, the 300-series use a wide range of V-speeds that vary based on flap setting and weight.
Here’s the idea of the “big numbers”: The day that I first learned of this technique – with the two pilots of
FEBRUARY 2024