Crosswind Chaos

5195
image: Alan Wilson | CC BY-SA 2.0

Several years ago, my father was visiting from overseas and we were both keen to attend a small fly in and airshow prior to him returning. I booked the Cub for the whole day. The destination was only about one hour away, and the flying display started at 1400. Plenty of time …

We woke up early and set off to the airfield. The weather forecast was for good conditions with a light wind but as we were getting the aircraft ready, the cloud base looked a lot lower than expected. Since we still had time to spare, I decided to wait a bit, hoping the weather would improve. Eventually after several cups of coffee, it looked slightly brighter, so we decided to give it a go as time was ticking on. By now, the wind had picked up quite a bit. It was not as forecast, but it was down the runway. At least the runway of our home airfield anyway!

After a pleasant flight we eventually arrived at the destination and landed just prior to 1400 when the airfield closed for the flying display.

After a nice afternoon watching the display and chatting to a few other owners we slowly got ready to depart. The sky looked fantastic—sunny with a few puffy clouds at about 5000 ft. The wind was however quite strong and at this airfield it was 90° across the runway and gusting.

I started the take-off roll with the stick hard back and slight into wind aileron and smoothly applied full power. The Cub started to roll normally but as soon as the tail began to lift the aircraft began to veer rapidly to the right, into the wind. I fought for all it was worth with full left rudder to prevent a rapidly approaching ground loop.

We departed the sealed runway and ran onto the grass runway which was alongside. Fortunately, there were no runway lights or other obstructions for us to hit. As we bumped across the grass the nose started to pitch forward towards the ground. I just managed to regain control enough to bring the tailwheel back down, albeit with a bump.

Just when I thought I had directional control back the aircraft suddenly began to veer in the other direction. Again, I fought it with all that I had and eventually, after a struggle, the aircraft crossed back onto the hard runway again and finally became airborne. After shakily climbing away we had an uneventful flight home and a smooth landing on a (thankfully) into-the-wind home runway.

So, what had gone wrong and why? I viewed the video footage of the take-off which my passenger had filmed. Hindsight is a wonderful thing. I could already see a few things which I should have done a lot better.

During the taxi the video showed the horizontal windsock, so the wind was at least 15 knots at 90° to the runway and gusting stronger. The Cub flight manual says max demonstrated crosswind is 10 knots. I’ve heard many pilots argue that ‘max demonstrated’ is not an actual limit. Most pilots probably think they can handle stronger crosswinds and I suppose I was one of them. In this case I had exceed the limit of my skill level. I certainly will use ‘max demonstrated’ as a hard limit now.

In any crosswind you must ensure you use sufficient into-wind aileron. When I watched the video, I realised I probably only had a quarter deflection. It wasn’t enough. More aileron means more weight on the into-wind wheel helping keep the aircraft tracking straight on the ground. It also stops the wing from lifting.

If it is all going wrong on a take-off then close the throttle and stop. For some reason stopping never crossed my mind but was probably the safest thing to do.

I suppose the sun and fabulous looking sky had lured me in to thinking it was great conditions for flying. Combined with the fact that we needed to be home, we decided to give it a go.

Get home-itis. We have all heard about it and like me, most people think they won’t succumb to it. I was one of them!

It can creep up on you very easily without you even noticing. Always be aware of it, even on small trips. There is always another day to fly or another way to get home.

7 COMMENTS

  1. Nice share. I have had one or two crosswind moments in my RV7. I found it doesn’t hurt to put full into wind aeleron then reduce as you accelerate and weather cock into wind as soon as the wheels are off the ground. But that just comes with practice. Thanks for sharing

  2. It does depend on prop rotation as to the maximum cross wind.. Put blade horizontal and one blade of prop will have no bight into are and other will bight air and thus pull more and cause a bad swing. Lycoming, rotax do not like a LH cross wind while Gypsy major and VW do not like RH cross winds.

    • Full aileron into wind at the start of the roll is the way to go – straight out of the old instructor’s manual.
      Not sure about stopping though: full power gives instant rudder response and the thrust vector counters some of the directional instability (on the ground) that is inherent in all tail-draggers.
      Could you have delayed raising the tail for a bit longer? Keeping the tail wheel on the ground for as long as possible also counters some of the inherent directional instability by providing drag (both tyre friction and aerodynamic) at the back.
      All part of a fascinating subject actually!

      ~ Dick Gower

  3. I always understood that full aileron deflection was needed at first, what’s the point in partial aileron? If yr going to go beyond what’s recommended by the A/C manuafacturer and become a hero test pilot you do so at yr own risk! That was incredibly irresponsible to even consider that t/off!

  4. Hey Walter, whilst it is acknowledge you have your haters and some admirers in this safety forum ..could you indulge us with some of your bloopers over your commendable 40 year career ?
    Back to topic ..for budgetary reasons I now fly LSA and these aircraft can sometimes be harder to control than heavier aircraft. I find no flap gives me better control with cross winds and gusty winds. btw ..I have just landed from a flight YCAB to YCAS and in 10 years time I might tell everyone about it :)

  5. Walter, you are clearly Gods gift to aviation and someone who has never made a mistake in his life. Your comments are never constructive or contribute anything positive or useful to aviation. Might be better if you refrained from commenting if you have nothing to contribute

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