Guest basscheffers Posted July 20, 2009 Posted July 20, 2009 Crosswind in the sporty seems a little confusing. The POH says max demonstrated 10kt, but if you read the training guide, Evektor says something like "beginner: 10kt, Novice: 15kt and expert: 20kt". So which one is it? If they have not demonstrated 20kt, how can they say in the training guide an expert can do it? From experience, a 15kt stable crosswind is not an issue. We trained in that and I have done it several times since. What would the legal limit be? The issue of course being that a crosswind constantly changing direction and changing between 5 and 10 knots is a much bigger challenge than a nice and stable 15kt one! Hard to make a black and white rule...
motzartmerv Posted July 20, 2009 Posted July 20, 2009 Yea, i have to say im a little dissapointed with the sporty flight manual.. It is the document we are sapposed to go off, and legally can't operate the aeroplane outside of the paramaters set out in it.. especially at a training facility.. And as you said the demonstraated x-wind is 10 knotts, in lew of a MAX xwind figure, all they leave us with is the demonstrated.. Jabiru 160's have a similar problem.. The demonstrated is 14 kts, so if the atis at camden says more then that component of x-wind is currently blowing, our aurcraft sit on the ground untill it changes.. Which is very annoying considering i (and others) have demonstrated it can be landed in x-winds well above this speed...
Guest basscheffers Posted July 20, 2009 Posted July 20, 2009 One of the issues is also: what to do when you are up? I took off from Aldinga on Sunday when Parafield METAR said 350@14, or 9kt cross according to my calculation. When I got there ATIS said 320@16, max 15 cross! 330 is that awful direction at Parafield where you get 60-70 degrees off both 03 and 26. What to do, fly to random other places to find a legal one? Most don't have ATIS, so you just have to (mis)judge the airsock yourself anyway. My solution (as before) was to just fly the approach and decide if it is safe or not myself. Judging by the fact I am here typing this, I guess I did OK. Didn't feel unsafe or out of control for a moment...
motzartmerv Posted July 20, 2009 Posted July 20, 2009 Yea, thats a curley one.. I think the prudent thing to do would be to divert ( if possible) and wait for things to improve.. If the TAF is forecasting x-winds above the max or max demonstrated then i guess its time to stay home and play the simulator.. But as we all know, not all forcast's are accurate, and alot of strips dont have a TAF facility anyway.. So an understanding of backing and veering is needed so we can predict what winds will be doing on the ground from an area forcast wind... The main issue i can see (besides the obvious safety one) is that were an accident to happen, the insurance would be voided due to operations outside qouted max X-wind capabilities.. so a bloke could be up for a pretty penny for bending the undercarriage, or worse..
facthunter Posted July 20, 2009 Posted July 20, 2009 Max crosswind component. The POH does give you some figures, but qualifies them in some way. The stated figure is relevant if you damage the aircraft as a result of the X-wind AND your ability to handle it. The insurer could get out of paying by quoting some figure, if you landed and came to grief with figures above the ones stated for the crosswind. max. The x-wind component also has relevance at the flight planning stage. You have to carry fuel to another aerodrome IF the forecast cross wind is above the MAX for the aircraft type. Regardless of ALL this, the PIC should determine if he/she can safely execute a controlled and safe landing in the prevailing conditions. The buck stops with the PIC. How do you judge this? Familiarity with your aircraft and your capability, and I would use crab angle as the prime indicator with a reasonably long final tracking on the centreline. Whether you use into_wind, wing down as a technique is up to you, but I am talking about assessment. If you are coming in sideways you are going to have to put in some work Are you and the plane (in combination) up to it? That is the question. Nev
Guest Qwerty Posted July 20, 2009 Posted July 20, 2009 I nearly came unstuck with this earlier in my flying. I was following a mate (both of us in Lightwing GR 912). He landed first in what looked like a challanging but OK crosswind. He got on the ground OK but near the end of his rollout at about 20 -25 kn ground speed (I guess), he copped a gust that swung him into a ground loop and into a fence. He and his plane were OK and he had assistance on the ground so I p!$$ed off home with my tail between my legs. LESSON; dont relax untill its tied down, ground loops happen.Cheers.
Guest basscheffers Posted July 20, 2009 Posted July 20, 2009 Taking ATIS as a legal guide also brings the following problem: you know how often we hear something like: "runway 21 wind 240 at 10 kt max crosswind 12kt." WTF!? How does that work?
facthunter Posted July 20, 2009 Posted July 20, 2009 How does it make sense? It doesn't. You will often get a wind with a gust factor. Ie 260 @ 10 kts- G 15 knots. Perhaps they are infering this. If not gusts then occasional (OCNL) a bit more. They are probably trying to be helpful, by quoting a max. They could be leaving themselves liable. (pity) Nev
Mick Posted August 27, 2009 Posted August 27, 2009 Crosswind in the sporty seems a little confusing. The POH says max demonstrated 10kt, but if you read the training guide, Evektor says something like "beginner: 10kt, Novice: 15kt and expert: 20kt". So which one is it? If they have not demonstrated 20kt, how can they say in the training guide an expert can do it? ... Sorry I am a bit late coming across this thread but I may be able to offer some useful info. I cannot lay my hands on a copy of the flight manual from our Sportstar ( sold 24-4010 over a year ago ), but I am sure it listed the max X-wind for that aircraft as 18 knots. Our Sportstar was the original version with the small fuselage fuel tank, one of the first 4 or 5 to come to Australia. I have no doubt the manuals have been re-written for the newer versions and to suit the all determining American LSA regulations. Now here's the twist...... I am sure that while doing some major homework on both the Aussie and American LSA regulations that somewhere buried in the fine print of the USA version was mention that demostrated X-wind ratings should be given with the aircraft in full-flap configuration . In reality not many of us would use full flap in any sort of strong X-wind, especially in an aircraft with as much flap as the Sportstar ( 50 degrees of split flap and a flap with a huge surface area ). My Skylark which has even bigger flaps relative to wing area and a full flap deflection of 40 degrees, giving a similar effect to the flaps on the Sportstar, has a max X-wind at 90 degrees to runway rating of only 11kts.:ah_oh: When I queried this with the manufacturer they confirmed that the figure given was for full-flap configuration, a cover-your-butt worse case senario. I have comfortably landed the Skylark in up to 23-25 kts X-wind while only using 10 or 21 degrees of flap. When you get to the end of a long X-country flight of say 3.5 hours covering 420nm conditions on arrival are not always going to be what was forcast ( or even hoped for! ). If you are arriving at a field with ony one strip Murphy's law says that it will be a X-wind. At this point what can an insurance company expect you to do? Run out of fuel trying to get somewhere else or take on the X-wind if as PIC you are confident of acheiving the landing safely? Personally I practice X-wind landings at a field with more than one strip so if it reaches a point where I am not confident, I can just switch to the into wind strip and land safely. By doing this I have developed a good idea of the limitations of both myself and of the aircraft I am flying. Hope this helps, Cheers Mick
Guest Maj Millard Posted August 28, 2009 Posted August 28, 2009 I suppose you could always tell the insurer that is was off and on, and you landed during a momentary lull.....................I'd like to see him prove otherwise........Facthunter is correct, ultimatly it is up to the PIC and captain of the ship to decide if the landing is within capabilities.............
Barefootpilot Posted August 28, 2009 Posted August 28, 2009 You'll find that almost all flight manuals with have "demostrated cross wind limit" its basically because they have to put something in there. All it means is during testing that is what was demostated maybe for several reasons such as that was all the wind they had when they tested the aircraft. As its been pointed out if you bend the aircraft above the demo limit you will getting a few questions from your insurance company but usually these limits are on the cautiouse side.
SilverWing Posted September 29, 2009 Posted September 29, 2009 SportStar crosswind The 'demonstrated' crosswind figure for the SportStar Plus and SL/MAX (wing tanks) is 21 knots 'by an experienced factory test pilot'. The LSA regulations require a quoted maximum crosswind figure at full flap 'capable of being achieved by a pilot of average ability'. The SportStar factory has thus begun to quote the mixed figures 10/15/20 kts quoted by basscheffers. Hope that clears it up.
Guest sunfish Posted March 23, 2010 Posted March 23, 2010 The issue with the Sportstar is that it has low ground clearance. If you don' land it very flat in a crosswind you will run out of aileron authority very fast if the wind gets under the upwind wing tip. that gives you gravel rash on the wing tip, aileron or worse.
J170 Owner Posted September 16, 2011 Posted September 16, 2011 One of the issues is also: what to do when you are up? I took off from Aldinga on Sunday when Parafield METAR said 350@14, or 9kt cross according to my calculation. When I got there ATIS said 320@16, max 15 cross! 330 is that awful direction at Parafield where you get 60-70 degrees off both 03 and 26. What to do, fly to random other places to find a legal one? Most don't have ATIS, so you just have to (mis)judge the airsock yourself anyway. My solution (as before) was to just fly the approach and decide if it is safe or not myself. Judging by the fact I am here typing this, I guess I did OK. Didn't feel unsafe or out of control for a moment... You can get a rough idea of x-wind by how much drift you apply on final. I figure if I'm not flying sideways, I'm good...
Guest davidh10 Posted September 17, 2011 Posted September 17, 2011 Don't insure the aircraft and it is then just up to you as PIC as to whether you and the aircraft can handle the conditions. Mine's not insured, so don't have the dilemma. If I bend it it, is my cost, regardless. That does not make me shy of cross-winds, but I fly within my and the aircraft's capability. One issue with judging x-wind on final is that on the ground it can be quite different to circuit height and conditions can change quickly. Here's some situations I have experienced that illustrate the point:- 40kn at cct height; 20G25 on the ground (was x-wind @ 30deg). Actually this was my strong x-wind training 8 touch & go + 1 full stop in an hour. I still had sore arms the next day. 30kn at cct height; windsock limp. flying final with a 35 degree crab, but straightened up with the last 50' 30kn southerly at cct height; 12kn northerly on the ground. Two wind socks at opposite ends of the aerodrome, blowing in almost opposite directions, about 7kn. Gust front from a nearby line of rain cells arrives just as I taxied off the runway. Wind changed from 15kn northerly to 20kn southerly in about 20 seconds. Close encounter with a dust devil on final, other conditions calm. A down draught on late final that required cruise power to maintain correct descent rate. Look at the windsock or all if there's more than one. Check the water on local lakes and dams. Watch for smoke and dust. Watch long grass for wind patterns. In rain, you can also look at the rain fall patterns on the ground and how it is being affected by wind and gusts. This latter is how I spotted the approaching gust front, mentioned above. I was watching it and constantly reassessing if I could land ahead of it arriving or would have to ride it out at altitude. I would not have wanted to be encountering it on late final. The reality is that x-wind is just one of the atmospheric impairments we have to deal with, as and when we encounter them. While having an up-to-date weather report including TAFs is really good to avoid predicted adverse conditions, I've also flown when the report was adverse, but the reality was fine and that could be seen before take-off. Local weather conditions can be very different to the Area Forecast and can even vary significantly between local aerodromes. Knowing the local weather characteristics and trends is very important if the weather is likely to be poor.
facthunter Posted September 18, 2011 Posted September 18, 2011 Variable crosswinds, dust devils, gusts are the stuff that prangs are made of. All planes are affected but the larger heavier ones handle these conditions better that light low wing loading aircraft. Usually there is less wind at ground level, but the cardinal rule is to go around and reassess the situation if you are not sure of having enough control in reserve to maintain positive control. The go-around is not a completely safe manoeuver, at times but it is the lesser of two evils generally. If you are low on airspeed, fly in ground effect when possible to gain speed, rather than climb at a very low airspeed where another gust may dump you on the ground, or result in an unusual attitude being established, or the aircraft stalling. If another contact with the ground is unavoidable then make sure that you yaw the plane to minimise side loads on the undercarriage and don't let the upwind wing get high. Nev
Nathan_wins Posted November 16, 2014 Posted November 16, 2014 I know it doesn't help the dilemma of a local flight...and I would hate to sound like a legal eagle (because I'm definitely not), but just wanted to mention/remind in case anyone had forgotten that the AIP ENR does mention that a PIC must provide for an alternate aerodrome if the crosswind or downwind component exceeds the maximum for the aircraft...like people have said it would be hard for an insurer to prove he magnitude of a crosswind...just thought I would note the point for anyone who was not aware...it would be good to know what the legality/weight of the term "demonstrated" brings to an insurance claim...not sure if it was stated earlier.
rhysmcc Posted November 16, 2014 Posted November 16, 2014 Taking ATIS as a legal guide also brings the following problem: you know how often we hear something like: "runway 21 wind 240 at 10 kt max crosswind 12kt." WTF!? How does that work? The wind quoted is an average, it could be 5knots either side of what's quoted. When max is quoted that's the highest observed. The direction is also and average, rarely do you get wind as a constant velocity.
Kregster Posted December 4, 2014 Posted December 4, 2014 Took an Evektor Sportstar for pattern during our "Santa Ana" winds. The Sportstar is a great LSA and handles very well. This video is about 12 months old and taken prior to me getting my certificate. I really appreciated my CFI letting me experience the "winds"... Runway 1R, tower calls winds 030@25G30. We did three landings and the winds varied on each. Awesome experience!
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