Most jets climb at 250 knots up to 10,000 feet due to FAA regulations. Above 10,000 feet, 280 to 300 knots with a transition to Mach . 7 around 24,000 feet are average for the 737. The Airbus will climb 250 knots up to 10,000 feet, then accelerate to 300 knots or a little more, then transition to Mach .