Max head tail wind sep /mep
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Many modern flight manuals I can think of provide performance information for tailwinds. Example, Cessna 172S, Figure 5-4 Crosswind Components provides data from a 15 knot tailwind to a 35 knot headwind to a 35 knot crosswind. Figure 5-5, Short Field Takeoff Distance, Note 3: "Decrease distance 10% for each 9 knots headwind. For operation with tailwinds up to 10 knots, increase distances by 10% for each 2 knots.". What information are you looking for?
For much older airplanes (pre 1970's), it was not a certification requirement to provide this information, so in some cases it was not published.
For much older airplanes (pre 1970's), it was not a certification requirement to provide this information, so in some cases it was not published.
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The "maximums" for the airplane will be presented as "limitations" (section 2 of a modern "GAMA" format flight manual). You are required to abide by these limitations. "Wind" is not presented as a limitation in a flight manual. Performance charts tell you what performance to expect from the airplane in the stated conditions, including wind. For the 172S, Cessna provides you with data for wind components from 35 knots headwind, to 35 crosswind, to 15 tailwind, with the note that the maximum demonstrated crosswind component (not a limitation) is 15 knots. They further give you takeoff performance data factors for head and tailwinds.
Neither of these are presented so as to limit the pilot in a decision to takeoff into a head wind, or with a tailwind. The decision to fly in any particular wind condition is a pilot judgement, rather than written flight manual value. But, I would also confer with the owner of the plane, they may have an opinion as to what winds they feel comfortable with you flying their airplane in!
Neither of these are presented so as to limit the pilot in a decision to takeoff into a head wind, or with a tailwind. The decision to fly in any particular wind condition is a pilot judgement, rather than written flight manual value. But, I would also confer with the owner of the plane, they may have an opinion as to what winds they feel comfortable with you flying their airplane in!
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Personally, I'd be a little circumspect about taking off into a serious headwind (say 25 kts or more) because I'd want to pretty quickly get to a speed where my safety wasn't compromised if it gusted (or un-gusted) and I'd need to be very certain that it wasn't going to back or veer by 45 degrees by the time I wanted to land.
My point being that it isn't the absolute windspeed that would concern me (unless I was in a 152 trying to take off into a 60 kt headwind) but the other circumstances or possibilities that were also a risk factor un the day.
My point being that it isn't the absolute windspeed that would concern me (unless I was in a 152 trying to take off into a 60 kt headwind) but the other circumstances or possibilities that were also a risk factor un the day.
U.K. CAA recommend not to fly if surface winds exceed 2/3 of the stalling speed of the aircraft. If you’re operating commercially you may think it a bit conservative, but for a C152 that would be a bit over 26 knots which is probably high enough for an averagely experienced PPL holder and their passengers.
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Had the rare experience as a teenage airport rat of helping a Chipmunk land, a gale blew up while the club machine was on a flight and upon his return was unable to land, wind in excess of stall, a group of members had to literally pull the aircraft out of the sky.
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U.K. CAA recommend not to fly if surface winds exceed 2/3 of the stalling speed of the aircraft. If you’re operating commercially you may think it a bit conservative, but for a C152 that would be a bit over 26 knots which is probably high enough for an averagely experienced PPL holder and their passengers.
Last edited by graziani; 18th May 2023 at 04:09.
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Today's flight was extended by an hour and a half to an alternate airport, as the wind came up, and the result was that my original destination airport, with one runway closed for construction, had a 17G26 knot direct crosswind on the remaining runway. I declined, and flew onward to the next airport, rather than try on the crosswind. I would not be able to explain to the boss why I tried it, if I groundlooped it! I may not know my limits, but I'm sure that exceeded them!
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In a lifetime of aviation I've never once heard of, let alone seen a limitation of headwind published or implied for any aircraft.
Windspeed limits for engagement of rotors, yes, but that's nothing to do with a take-off or landing limitation.
Ever.
Windspeed limits for engagement of rotors, yes, but that's nothing to do with a take-off or landing limitation.
Ever.
I mostly ignore tower and ATIS wind reports. What I care about is what the windsock closest to the landing point is showing.
Last edited by EXDAC; 19th May 2023 at 12:46.
