It would be foolhardy for a private pilot aspirant to announce to the designated examiner an intention to demonstrate no exceptional skill or alertness during a practical test, and let’s hope no flight instructor would recommend such an applicant for a checkride. In one area of pilot and aircraft performance, however, there is a bare-minimum ability to function safely that sets a bar of sorts.
Keep that in mind the next time you hear a pilot make the statement that a particular aircraft “can handle” a direct crosswind of this many or that many knots. Although the statement may have been proven true during aircraft-certification testing, it may not be an authentic predictor of a positive result each time a different pilot sits down at the controls. That’s why, for airplanes certificated after May 3, 1962, you can look up its “demonstrated crosswind velocity”—a figure most student pilots are sophisticated enough to point out is not a limiting value, but simply one that has been “demonstrated.”
But demonstrated by whom? If it had been demonstrated by a Patty Wagstaff or a Chuck Yeager, or some other aviation luminary, the number would not have much use as guidance for those in training or of modest experience.
When a Cessna 172 went out of control on landing in a gusting crosswind at a Wisconsin airport in the fall of 2017, the 103-hour pilot recounted a “huge gust of wind” that “took the plane and just threw it to the right,” resulting in the propeller striking the ground, substantial damage to the left wing, and the aircraft nosing over.
The National Transportation Safety Board’s report on the accident (on Runway 26, with wind from 190 degrees at 9 knots, gusting to 17 knots) said the probable cause was the pilot’s failure to maintain directional control in the gusting conditions.
The NTSB also noted language in the airplane’s pilot’s operating handbook: “The maximum allowable crosswind velocity is dependent upon pilot capability rather than aircraft limitations. With average pilot technique, direct crosswinds of 15 knots can be handled with safety.”
A similar definition appears in the Airplane Flying Handbook, noting that before certification, an airplane “must be flight tested and meet certain requirements. Among these is the demonstration of being satisfactorily controllable with no exceptional degree of skill or alertness on the part of the pilot in 90-degree crosswinds up to a velocity equal to 0.2 VS0. This means a windspeed of two-tenths of the airplane’s stalling speed with power off and landing gear/flaps down.”
The POH for a 1980 model Cessna 152 offers yet another wording of the term as “the velocity of the crosswind component for which adequate control of the airplane during takeoff and landing was actually demonstrated during certification tests. The value shown is not considered to be limiting.”
So if the demonstrated crosswind velocity is not considered limiting, what is?
Finding your safe limit comes from practice and experience in which you and your flight instructor focus on establishing a reasonable parameter—perhaps at a velocity lower than the published demonstrated crosswind velocity.
Numbers aside, the Airplane Flying Handbook offers pilots of any skill level a strong cue for identifying conditions exceeding the airplane’s, and the pilot’s, capacity to cope: “If the crosswind is great enough to warrant an extreme drift correction, a hazardous landing condition may result.”
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