1.3 Vso on a glide angle over obstacles to short final, a quarter to eighth mile out depending on that airspeed, is an effective way to get airspeed and altitude reduced to a logical deceleration point. Deceleration is necessary to touch down slowly and softly.

Most pilots are taught to close throttle and begin this deceleration over the threshold or fence at a height that the resultant round out and hold off is manageable. 1.3 Vso, at this point, keeps the wing flying in ground effect a considerable distance down the runway.

Sanctioned training materials and techniques call for a .1 Vso reduction in airspeed to the round out point for short field landing. Pilots find this excessive kinetic energy, airspeed, very difficult to manage using sanctioned techniques.

In our search for a more effective deceleration point, but not stall out of ground effect, let's first throw out what doesn't work here: the airspeed indicator. We are stabilized at 1.3 or slow enough to achieve sufficient deceleration between the deceleration beginning point and touchdown below Vso. There are many more accurate indications of sufficient deceleration: changing relative wind noise, changing control feel, changing pitch attitude, changing buoyancy feel, MAINTENANCE of APPARENT BRISK WALK rate of closure (rate of closure will appear to speed up at close range), changing engine noise (If decelerating properly aircraft will lose altitude requiring more power.)

The reliable point, regardless of descent angle or wind conditions, is the point where rate of closure appears to speed up. This takes practice to get out ahead of the airplane because it will jump on us until experienced and not come at all when deceleration is adequate. The really big training advantage of the apparent brisk walk rate of closure is that everybody, including pilots, already know how to manage it and do so at every stop sign. None of us use the speedometer to decelerate at intersections..

But there are other ways to eliminate the round out and hold off. We can drag it in behind the power curve. Where no obstacle exists, we can hover taxi in ground effect to the desired touchdown spot and then reduce power.

All methods, save round out cut power and hold off, are power pitch. The classic spot landing, without power, requires some threshold for safety. Power pitch approach, hopefully to flair, requires no threshold.

Rather than a search for an airspeed that doesn't solve the short field problem effectively, we need to find a begin deceleration point that works for us and make it default for adequate practice.

Contact wrote.

“The reliable point, regardless of descent angle or wind conditions, is the point where rate of closure appears to speed up. This takes practice to get out ahead of the airplane because it will jump on us until experienced and not come at all when deceleration is adequate. The really big training advantage of the apparent brisk walk rate of closure is that everybody, including pilots, already know how to manage it and do so at every stop sign. None of us use the speedometer to decelerate at intersections..”

This is even more true for the California rolling stop. Or the one they do in parts of Mexico. Good training for landings although in some jurisdictions this will get you a ticket.

Best,

Tom

Yes, we do the rolling stop in airplane. The irritating thing about airplanes is how the instrument panel keeps moving up into the windscreen as airplanes get newer. That makes the numbers go under the nose sooner. With older airplanes, we could use the apparent rate with the numbers until flair. Cessna's 40 degrees flaps help us see down there but now we have to imagine where the numbers are.

In automobile, visibility is even better with the short nose on newer cars. Looking around and seeing what is happening is critical in either machine.

I'm glad you started this thread Jim because I've been pondering something closely related and I need someone smarter and more experienced to explain whether my musings are correct. Sorry in advance for the thread drift.

I bought and installed a AoA indicator like the one Motoadve uses. In calibrating it I've documented that my plane stalls will full flaps and a bit of power at about 48mph. Perfect, I thought, I can come in much slower than I was taught (70mph) and touch down on the water nice and slow.

BUT-- playing around in slow flight at altitude I realized that my plane might keep flying at 50mph but the nose would be so far up it would be a terrible (or dangerous) water landing. At 55mph with the nose in a landing attitude I'm sinking faster than I would like to hit the water.

I've realized that all through my meagre 250 hours of training and flying I've confused sink with stall. I thought I was stalling it a few inches above the runway and greasing it in but in truth I was just experiencing sink which is a function of my landing attitude and I was probably a good ways away from a proper stall.

So, a stall is when the wing looses lift and controllability. Sink is when the attitude will not provide enough lift to maintain altitude, but it is still providing lift and control. If these are true, why do people talk about a perfect landing being a stall a couple inches from the runway when really they are managing sink, not a stall?

Albravo,

That last paragraph is an excellent description of sink or mush verses stall. I can't help on float landing, but we want to get near stall in low ground effect, this is much easier with power, before leveling to wheel land. Ask MTV if that works for floats.

contactflying wrote:MAINTENANCE of APPARENT BRISK WALK rate of closure.

Contact, please explain this in laymen’s terms. Thanks!

Start with your pickup truck driving into a stop light intersection. Far out, you seem or appear to be approaching the light at a brisk walk. As you get closer, things appear to speed up causing you to decelerate. By decelerating, you cause the rate of closure to appear not to speed up. By decelerating, you maintain the apparent brisk walk rate of closure.

Now look at a forward target from the cockpit of your airplane. Regardless of true airspeed, you appear to be closing with that target at a brisk walk. Move on down to 1.3 Vso on long final. You appear to be approaching, closing with the numbers at a brisk walk. About the time you really start to get busy on one quarter to one eighth mile final, the rate of closure with the numbers appears to really speed up much faster than a brisk walk. How can this be? You are still at 1.3 Vso.

Too late now on that approach. You are going to have to round out and close the throttle, and you are going to hold off until the airplane decelerates below Vso to the actual airspeed the wing stalls in low ground effect.

So next time anticipate the speed up of the apparent rate of closure, faster than a brisk walk, on short final and prevent it by pitching up further and adding more power. If you pull back and go up now, you are going too fast. If you add power and go faster now, you are going too fast.

By decelerating in time to prevent speed up of apparent rate of closure, that is by maintaining the apparent brisk walk that has been there all the way down the glideslope until now, you will slow with e elevator and hold glideslope with power.

At first, and when not current, you will still have to round out and hold off because catching it takes practice. As you get ahead of it and maintain the apparent brisk walk rate of closure until the numbers go under the cowl, you will find you only have to flair onto the numbers and close the throttle.

Elevator is generally just more and more back as we feel it on, the same as after the long hold off. Throttle, however, is dynamic. Sink, for whatever reason, add power. Balloon, for whatever reason, reduce throttle. In strong gust spread we may add full throttle and then adjust and close throttle and then adjust. We could just go faster, but that gives up the slower groundspeed advantage of headwind component. It is really bad technique to go off the end of the runway with headwind component advantage. And by adding airspeed, we give up the angle across the runway in strong crosswind.

Contact,

I have related very well to most of what you have posted here over the past several years. I have spent most of the past 30+ years flying off airport. The methods you promote are very valid in a “non-standard” flying environment.

I have often refrained from commenting when others have been challenged with understanding your methodology and/or terminology, as I am personally challenged with most communication over social media.

Reading these words in this last post, “you will slow with elevator and hold glideslope with power” prompted me to comment. I believe that many of the folks that have been challenged with the “apparent brisk walk rate of closure” concept, may be able to better understand that terminology and better relate to the pitch/power concept.

Keep posting and keep trying to relate and get through to those who have not had the opportunity to experience the very real world flying conditions you are trying to articulate. I encourage you to continue trying to use alternate terminology to try and get your thoughts across. I believe your teachings have the potential to save lives.

I encourage those who are challenged with Contacts methodology and/or terminology to read his posts, and his book or ebook, with an open mind. I also encourage you to follow Nushi’s lead and ask for clarification if necessary. If you are fortunate enough to be in the vicinity and have the opportunity to fly with him, do!

Contact, I hope to have the opportunity to fly with you one day as well. If you have the urge to wander up Yukon, Canada way, let me know. We will certainly accommodate you and line up some flying.

UpNorth

Thanks, UpNorth,

I don't handle cold well anymore, but you guys are hot now. I was headed to Fairbanks to do a seminar/clinic with the state biology guys in 09. I crashed an ultralight with its owner and spent several months in the hospital instead. I hope to make Grande Prairie again sometime.

As I tell primary students who are looking for someone teaching flying now, "there are lots of Contacts out there. Most have sense enough to keep their head down. "

Keep flying. Not a lot of money in it, but it's fun.

Contact

.

contactflying wrote:Start with your pickup truck driving into a stop light intersection. Far out, you seem or appear to be approaching the light at a brisk walk. As you get closer, things appear to speed up causing you to decelerate. By decelerating, you cause the rate of closure to appear not to speed up. By decelerating, you maintain the apparent brisk walk rate of closure.

........

So next time anticipate the speed up of the apparent rate of closure, faster than a brisk walk, on short final and prevent it by pitching up further and adding more power. If you pull back and go up now, you are going too fast. If you add power and go faster now, you are going too fast.

By decelerating in time to prevent speed up of apparent rate of closure, that is by maintaining the apparent brisk walk that has been there all the way down the glideslope until now, you will slow with e elevator and hold glideslope with power.

..........

Elevator is generally just more and more back as we feel it on, the same as after the long hold off. Throttle, however, is dynamic. Sink, for whatever reason, add power. Balloon, for whatever reason, reduce throttle.

Contact, first of all, thanks for the explanation. I cut your post up into the items that really resonated with me; what you mean is now very clear. I have heard what you explained expressed differently as UpNorth mentioned with the pitch/power method but it seems the general school of thought in primary instruction is a high, stabilized approach at speeds that aren't real world down to a round out and ground effect. Sometimes that works well, sometimes I float it past my spot and sometimes, although rarely, I end up dragging it in. It just seems inconsistent....the pitch/power or apparent brisk walk rate of closure method seems far more reliable in a real world setting but unfortunately isn't taught by many primary instructors in short field landing techniques. Why is that?

.

Nushi,

We instructors were pretty much on our own and taught in various ways before the Practical Test Standards brought in integration of instrument with contact skills and the stabilized 1.3 Vso approach. Both were fairly successful in standardization of instruction and reduction of landing incidents and accidents.

When the FAA makes big changes like those, there is a period when they invite comment from operators, instructors, pilots, mechanics, and the public. After that they are very rigid in interpretation and expect compliance. While the resultant techniques do not carry the same legal force of Federal Air Regulations, much pressure is exerted on instructors to conform, mostly by peers.

In writing an operations manuel for an Ag school for example, techniques must be identical to those in any other flight school. Some Ag instructors go by the written operations manuel. Most, however, read between the lines. In the Army we called this a workaround.

Runways now are much longer than the common short, grass Muni or municiple I learned on. The school solution generally works. In other situations a workaround may provide greater efficiency and therefore greater safety. There are teachers of contact flying out there who will work with you. While workaround techniques can solve problems, they are generally not compliant with the standards.

For those not familiar with or comfortable with the airplane hover taxi, consider the classic soft field landing. Done well, that is to touchdown as slowly as possible, we will hover taxi in low ground effect to touchdown with power. Power is necessary to hover, and certainly to hover as slowly as possible. Yes, we will be slower than Vso.

A good way to work toward slowing sufficiently to tackle truely short fields is too work to bring the touchdown point further and further back from well down the runway on soft field landing.

By decelerating sufficiently to require considerable power to touchdown on the numbers, we automatically soften this slower than Vso touchdown on the numbers. The strangeness of this slow and this much power, for round out and hold off pilots, will lead to too fast (need to round out) or too hard (not enough power) landings at first. Getting there means consistent, default touchdown slowly and softly on the numbers. It is like ice cream on cherry pie.

I have covered dynamic proactive control movement before in earlier threads. While best for rudder only longitudinal axis alignment (directed course to the target) and finding nose attitude with elevator to maintain hover altitude, it doesn't work to find the point where we should begin deceleration. Pitching up early to get outside the begin deceleration point would get ahead of the rate of closure apparent speed up. We would, however, end up dragging it in out of ground effect.

Like some move the round out back to get the hold off started earlier, we need to creep back (on the next approach) a bit. Late begin decelerate point, apparent rate speed up is very apparent. A bit sooner begin decelerate point, apparent speed up still visible. Perfect begin decelerate point, no apparent speed up. Perfect begin deceleration point results in maintenance of the apparent brisk walk rate of closure from start of long, or short, final to touchdown on the numbers slowly and softly.

The apparent brisk walk rate of closure is a very common thing all industrialized people have observed many times in many types of vehicles. All drivers have learned to maintain the apparent brisk walk rate of closure by slowing down as they speed toward targets they don't want to crash into. Pilots, on the other hand, have been operate managed into the belief that they must stabilize their airspeed at 1.3 Vso until beyond this natural begin deceleration point.