Single-engine Class B - Landing — Page 327, Lesson 402

Let’s start with the single most important idea for landing a single-engine Class B aeroplane: there is only one regulatory requirement, and it’s beautifully simple. The landing distance must not exceed the landing distance available. In plain terms, the aeroplane must be able to come to a complete stop within the physical length of the runway you intend to use. Now, where does this rule live? The requirements for single-engine Class B landing are found in CAP 698, and the operational rule itself comes from EU-OPS. EU-OPS states that the operator must ensure that the landing mass of the aeroplane, for the estimated time of arrival, allows a full stop landing from 50 ft above the threshold within 70% of the landing distance available — and this applies at the destination aerodrome and at any alternate aerodrome. Let me unpack that carefully, because every phrase matters. “Landing mass” means the weight of the aeroplane at the moment of landing, and you must check it for the estimated time of arrival — that is, the predicted time you’ll actually touch down, not some arbitrary planning figure. The landing must be a “full stop landing,” meaning the aeroplane comes to a complete halt, not just a touch-and-go. And the measurement starts from 50 ft above the threshold — that’s the standard reference height from which landing distance is measured. The key constraint is that this full stop landing must be achieved within 70% of the landing distance available. So the rule isn’t “land within the runway.” It’s stricter: you must be able to stop within 70% of the runway length. The factor used for this calculation is 1.43. Why 1.43? Because 1 divided by 0.7 equals approximately 1.43. That factor is your tool for converting between the 70% requirement and the actual distances. Let me walk you through the first example to make this concrete. Suppose the landing distance available at the destination airfield is 2200 ft. The aeroplane must be able to land within 70% of that. To find 70% of 2200 ft, you divide 2200 ft by 1.43. Carrying out that calculation gives 1538 ft. So 1538 ft is exactly 70% of 2200 ft. Therefore, the aeroplane must be able to achieve a full stop landing within 1538 ft. That’s the maximum landing distance the aeroplane is allowed to require at that airfield. Now, there’s a second way to look at the same requirement, and it’s the reverse problem. Instead of starting with the runway length, you start with the aeroplane’s landing distance. Suppose the landing distance of the aeroplane is calculated to be 1200 ft. What is the minimum length of landing distance available that would allow a pilot to comply with the 70% rule? Here you simply multiply 1200 ft by 1.43. That gives you the minimum runway length required. So the two operations are mirror images: divide the available distance by 1.43 to find the allowable landing distance, or multiply the required landing distance by 1.43 to find the minimum runway length. Let me make sure the logic is crystal clear. The 70% rule means the aeroplane’s demonstrated landing distance can only use 70% of the runway. So if the runway is 2200 ft, the aeroplane may only need to stop within 1538 ft — that’s the 70% slice. Conversely, if the aeroplane needs 1200 ft to stop, the runway must be at least 1200 ft divided by 0.7, which is 1200 multiplied by 1.43, giving roughly 1716 ft. Both directions use the same 1.43 factor, just inverted. One more critical point: this requirement applies not only at the destination but also at any alternate aerodrome. So when you plan a flight, you must verify the landing performance at every airfield you might use, not just your primary destination. That’s the complete landing requirement for single-engine Class B. The single rule, the 70% constraint, the 1.43 factor, and the two ways to apply it — dividing the available distance or multiplying the required distance.