Proactive-dominant v. reactive control inputs for high gust landings
A technique I've developed and used with consistant success, predominantly in gusty winds above 30 knots direct/variable crosswind, uses proactive-dominant control inputs rather than predominantly reactive control inputs. With the latter method unless dead-on with control inputs, porpoising or a hard landing is a common result, as pertaining to elevator inputs and wing tip to surface contact can result pertaining to aileron inputs. The reason the reactive method starts to fail sooner is due to natural limits on neurosomatic reaction time to unseen gusts of even the most seasoned and quick reflexed of pilots.
The way the proactive-dominant method gains time over reaction time is by BOTH putting in a predetermined amount of anticipated over-control to one or more of the airframe controls required while immediately following it by a corrective OPPOSITE control force while simultaneously observing by aircraft's attitude and assessing how much force was actually required for the maneuver in the high gusts.
Let's look only at isolating pitch attitude on landings (although the same method is used for aileron and rudder inputs, and even power setting) to avoid porpoising on sea or land. Immediately after a too hard/fast touchdown one may find oneself re-launched back into the air by an unseen boat wake or something. The proactive-dominant method uses about 50% more down elevator than is anticipated to be needed to send the nose back down to avoid the tail first landing, immediatly followed by the OPPOSITE up elevator in an amount to correct pitch attitude as needed.
3 typical results will be observed regarding the application of the 50% "extra" nose down control; 1. It will be too much and therefore the already started opposite, nose up input will be correct. 2. It will be too little and the already started opposite, nose up input can be eased off a bit to become more correct. 3. It will be just right and the touchdown can be followed through to full landing on sea or land.
This whole process is repeated (very rapidly) over and over again as needed by fractions of a second until landing is complete, and is also applied to the other 2 major control inputs as needed and also can be used for engine power in a similar way. It is much faster to actually apply it in practice while landing than to read or write about it. The reason for the success of the proactive-dominant method is in the elimination of some of the reaction-time component of the gusty landing task
time-line. The reactive method requires all of the fraction of a second of reaction time that is the minimum reaction time typical of the well-trained human in optimum condition.
Since a new flight student may find normal landings with little or no wind just as challenging as high wind landings to a more experienced pilot, I have employed it with success in those teaching situations from time to time at that level. When done correctly, the flight path and aircraft attitudes will be far from "smooth" but, the resulting landing will be successful even in the most demanding of situations.
Pilots' attempts at what they conceive of as proper, "smooth" flight is what can often limit their success in higher levels of aviation accomplishment such as landing in high gust winds that most average pilots never even see, let alone do. As has always been the case, the penalties for failure in aviation remain potentially high regardless of method practiced so, often times it is best to not even get in an aircraft.
Interesting theory but sounds like a real arm wrestling match. I used to try to "fight" the wind excursions in heavy x-wx and try to anticipated what the wind would do from one second to the next - good luck. The guy who taught we float flying actually (after 15 years of land flying) actually taught we how to fly. This guy used to land a j3 cub onto his brothers moving pickup truck with a 20 know x-wx! (Yep he really is that good). When he observed me making many rapid control inputs to correct for excursion in heavy x-wx he memorably asked me what the heck (my word not his) I was doing. Forget the excursions, make smooth slow corrections, dont over control and remember it doesnt matter where the plane is until just at the point of touch down. I have never worried or fought a turbulent ride onfinal since! - Thanks Rick!
I am familar with that method too and use and teach it extensively for up to moderate conditions. As stated, this proactive-dominant method is in my 20 year practice -not therory.
Originally Posted by Marlin
It doesn't sound like you're flying in really strong, variable gusts with that reactive method. In such heavy, 30 knot+ gusts, if one doesn't "fight" them as you say, they would flip the plane immediately. If you read carefully, you will see there is no anticipation involved or mentioned in proactive-dominant, as the method has nothing to do with anticipation of often invisible wind gusts.
Smooth, slow corrections will never cut it in rapidly swirling gusts the 30+ knot magnitude. Slow corrections and rapidly changing, 30+ knot gusts are mutually exclusive and a guarantee to allow the airplane to be flipped.
Also, it most certainly does matter a whole lot where the aircraft is well before touch down, unless you're on some huge, wide runway and even then one may as well use the opportunity to practice staying on the centerline.
Last edited by CFII; 03-10-2012 at 06:39 PM.
I actually agree with that entirely.. I have always used proactive control inputs.
RE: "In such heavy, 30 knot+ gusts,"
Hard to tell if you're seriously trying to provide advice/instruction here, or just boasting. Can anyone tell me why someone would want to go fly their seaplane on the water with winds in excess of 30 knots?
CFIs get these types of questions fairly often.
Originally Posted by predmond
As to the "why", there are 2 primary reasons:
A pilot may, in spite of all due diligence in preflight planning get caught in such conditions where an extremely challenging crosswind landing is the best, or only option. Such a scenario has a higher probability of occurring in more remote flying destinations but, can occur almost anywhere.
A pilot may also, simply wish to voluntarily fly to higher limits, both to increase proficiency of perishable flying skills or for other personal reasons.
As our private pilot training told us, know your personal limits and respect the fact that at whatever level they are at, they are perishable flying skills and should be properly brought to renewed proficiency on a regular basis.