Aus einem Artikel, den der Chef der Flight Operations-Abteilung von Cirrus Aircraft vor einiger Zeit verfasst hat:
One of the most common problems we’re seeing,” says Bill Stone, Director of Flight Standards & Operations, Cirrus Design Corporation, “is that the minute there’s any substantial crosswind component, some pilots are landing with half-flaps or even no-flaps.” Stone says that what some pilot may not be realizing is that the maximum demonstrated crosswind for the CIRRUS (20 KIAS for the SR22 and 21 KIAS for the SR20) was conducted using full flaps, and that it’s the intention of the manufacturer that full flaps be used for all normal (non-emergency) landings.
“There is a fallacy,” says Stone, “wrongly passed on from misinformed instructors or from other manufacturer’s airplane flight manuals that leads pilots to think that they have greater control over their plane during the landing phase with less than full flaps. The assumption is that the greater speed creates better control. In reality, that extra speed during the transition from flight to landing can actually cause a pilot to lose control. At the least it’s going to increase your landing distance, and possibly subject the gear to higher side loads”
Stone says another reason some pilots have been landing with less than full flaps is due to the lower pitch attitude view seen out of the forward windscreen. “They may have a bit of apprehension concerning crosswinds, and think that if they fly a flatter approach attitude by using reduced flaps, they’ll have better control. Again – they won’t. The steeper angle, and the lower speed afforded by full flaps, is the safest method and the recommended procedure for landing CIRRUS airplane.”
Stone is emphatic that any of the CIRRUS airplane, “can and should,” be landed using full flaps even with winds at or near the max demonstrated. When asked about landing in conditions with winds above the max demonstrated, Stone says that it’s not advised. “It’s not a defined limit of the airplane, but it is the limit of what wind was tested. If you go beyond that, it’s not illegal but we don’t advise it. In fact, in some cases, we recommend setting personal minimums which may be lower based on your experience, flight time, proficiency, and recency of experience.”
Stone adds that a steady wind is generally much easier to handle than a gusty crosswind situation and to be cognizant of the gust factor so that it doesn’t exceed either the demonstrated capability of the airplane, or the ability of the pilot.
In terms of landing procedure, CIRRUS recommends treating a crosswind landing the same as a normal landing by using the same landing speeds and full flaps. If there are gusty wind conditions, Stone says pilots should add one-half the gust factor to their approach speed. “Let’s suppose a wind of 12 knots gusting to 20. In that scenario, the pilot should calculate his landing speed by subtracting the steady state wind – in this case 12 knots – from the gust speed of 20. That leaves 8 knots of gust factor, and half of that – or 4 knots – should be added to the approach speed.
It’s important to remember that when compensating for wind gusts by padding your indicated approach speed, you do NOT take the steady-state wind into account – ONLY the gust factor. To make sure it’s clear, let’s run through another example: Suppose you’re approaching in the SR20 and the surface wind is being reported as 11 knots, gusting to 21. In that case, if you subtract the steady state wind of 11 knots from the peak gust of 21, you’re left with a 10 knot gust.
To determine your final approach speed, simply take ONE-HALF of that gust factor - which would be 5 knots - and add that to your normal published approach speed. In any event, since the max demonstrated crosswind for the SR20 is 21 knots (and 20 knots for the SR22) it’s highly unlikely that a pilot would find himself landing with anything greater than a 10-11 knot gust, which means that it would be a rare event to ever pad your approach speed by more than 5-6 knots to compensate for wind gusts.TECHNIQUE: Crab, Sideslip, or Both?
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Ganzer Artikel:
https://www.kineticlearning.com/pilots_world/safety/07_05/article_07_05_1.html