Crosswind Limits
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Crosswind Limits
My aircraft POH says, "a pilot of average skill should be able to safely land in a 15kt crosswind", and a placard inside the aircraft says, "maximum demonstrated crosswind 16kt". Nowhere is the word "limit" used.
Does this mean that it's down to the pilot's judgement? Or would an insurance company drop you like a hot potato if you had an 'incident' during a landing outside the crosswind limit?
Does this mean that it's down to the pilot's judgement? Or would an insurance company drop you like a hot potato if you had an 'incident' during a landing outside the crosswind limit?
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Yes it is down to pilot skill and judgement and no it would not invalidate your insurance if you prang it during a landing with a 17kts X-wind.
It is not a lmitation.
IF my memory serves me well manufacturers only have to demonstrate that their mount is able to be landed with a crosswind component of at least 0.3Vs.
Nowt more nowt less.
That is why some STOL aeroplanes have a ridiculously low demonstrated crosswind, their stall speed is low so 0.3 * is going to be very low.
Maule = 12 mph.
They easily handle a lot more.
It is not a lmitation.
IF my memory serves me well manufacturers only have to demonstrate that their mount is able to be landed with a crosswind component of at least 0.3Vs.
Nowt more nowt less.
That is why some STOL aeroplanes have a ridiculously low demonstrated crosswind, their stall speed is low so 0.3 * is going to be very low.
Maule = 12 mph.
They easily handle a lot more.
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if it is not in the Limitations section of the POH, it is not a limit.
The factory test pilot was required to demonstrate a safe landing under available crosswind conditions using NO crosswind compensation (= very ugly). The test proved that the landing gear is strong enough to handle idiot pilots.
The factory test pilot was required to demonstrate a safe landing under available crosswind conditions using NO crosswind compensation (= very ugly). The test proved that the landing gear is strong enough to handle idiot pilots.
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Thanks chaps. I've landed it with 16kt cross a number of times and the aircraft feels well within its capability. Always worth knowing the facts which are, as usual, at odds with clubhouse propaganda.
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The C152 POH says there is a DCC of 12kts but it is not considered to be a limitation. From personal (supervised by a FI) experience it can be landed safely in a much greater crosswind than that - NOT that I would set out to do that, it's just good to know that, should the need arise, it can be done. 
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Agree on that count. When I was a student I (with instructor) landed a 152 in 25kt cross. It squirmed a bit, but no major problems.
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The factory test pilot was required to demonstrate a safe landing under available crosswind conditions using NO crosswind compensation (= very ugly). The test proved that the landing gear is strong enough to handle idiot pilots.
Does remind me of something else though. Apparently a 747, because of the outboard underwing engines, can't use the wing-down technique to land in a crosswind. So the recommended crosswind technique is exactly what's written above - no crosswind technique whatsoever. Just plonk it on the runway like you normally do, with up to 45 degrees of crab. The gear is strong enough to survive this, and since the main gear is behind the center of gravity, it will ensure the plane aligns itself with the flightpath/runway anyway. Videos on youtube, search for "fantastic video of crosswind landings"
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So the recommended crosswind technique is exactly what's written above - no crosswind technique whatsoever. Just plonk it on the runway like you normally do, with up to 45 degrees of crab.
Not all big jets can do that though....the MD11 apparently responds very badly to being plonked down still in the crab.
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It squirmed a bit, but no major problems.
I know it's not all that popular in some circles, but I really enjoy flying it. It won't be that long before it's considered a "Classic" and then they'll all want to fly it. 
The factory test pilot was required to demonstrate a safe landing under available crosswind conditions using NO crosswind compensation (= very ugly).
This came up a while back and I posted a link and some extracts here.
http://www.pprune.org/forums/showpos...6&postcount=18
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The crosswond is demonstrated using both the crab and the forward slip techniques.
If the test pilot finds that one technique is unsuitable for the average pilot then the expected technique will be put in the flight manual.
The aircraft undercarriage must be capable of withstanding certain sideloads etc as per FAR-23 or CS-23 as appropriate. This may not be part of the flight test programme if the certifying authority accept an alternative method of demonstrating compliance.
The maximum crosswind demonstrated during test flying of the aircraft is specified in the flight manual. If you choose to use a higher figure then feel free to be a test pilot. However, please check your insurance for the small print about using the aircraft for development testing.
When you have demonstrated the higher crosswind, please let the manufacturer know......they will either amend the flight manual or recomend that you have the aircraft checked due to undercarriage side load limitations.
I wonder which?
Regards,
DFC
If the test pilot finds that one technique is unsuitable for the average pilot then the expected technique will be put in the flight manual.
The aircraft undercarriage must be capable of withstanding certain sideloads etc as per FAR-23 or CS-23 as appropriate. This may not be part of the flight test programme if the certifying authority accept an alternative method of demonstrating compliance.
The maximum crosswind demonstrated during test flying of the aircraft is specified in the flight manual. If you choose to use a higher figure then feel free to be a test pilot. However, please check your insurance for the small print about using the aircraft for development testing.
When you have demonstrated the higher crosswind, please let the manufacturer know......they will either amend the flight manual or recomend that you have the aircraft checked due to undercarriage side load limitations.
I wonder which?
Regards,
DFC
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Apparently a 747, because of the outboard underwing engines, can't use the wing-down technique to land in a crosswind. So the recommended crosswind technique is exactly what's written above - no crosswind technique whatsoever. Just plonk it on the runway like you normally do, with up to 45 degrees of crab.
I say this as a pilot of low wing jet airliners!
As for maximum demonstrated crosswind, whilst it may be LEGAL to exceed it, it's probably not SMART. As it is the maximum demonstrated, no-one can say for certain what the actual maximum safe crosswind is. Therefore, any excursion beyond the demonstrated maximum is a journey into the unknown.
Think about it this way - juggling with chainsaws is legal - but is is SMART for the average person to do it?
We have a simple rule at our FTO - we treat the maximum demonstrated as a limit. Full stop, no questions. That way we all know where we stand.
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How does a properly executed wing-low landing put sideload on the undercarriage again?
The maximum crosswind demonstrated during test flying of the aircraft is specified in the flight manual. If you choose to use a higher figure then feel free to be a test pilot.
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Have you ever carried out a perfect x-wind landing where this has been the case (no side drift, nose pointing exactly ahead)?
I flew recently with a friend who learnt at Sherburn. As we headed back towards Leeds I had a listen to the ATIS and the surface wind was 260/14 for runway 32. The whole concept of flying sideways on final, then landing left wheel, right wheel, then nosewheel was completely alien to him.
Not saying I'm any better or worse a pilot than anyone else, but I know how to land with a crosswind. It's a handy skill, maybe more people should learn it
