Except for Hotrod180, I have received little feedback on this approach. I realize the terminology is seldom used outside Army aviation. My question is, does this apparent increase in closure rate as you approach the fence cause any response. Are you already slow as in the drag it in or as in Patrick Romano's cord flat with horizon approach?

We all use stall and slow flight attitude, relative wind noise, control firmness, elevator position, and kinetic buoyancy either in lieu of or after round out. Does apparent rate of closure consciously or unconsciously factor into your techniques?

The book says we hold 1.3 until round out, but I see much slower approaches than that in the videos. What are you guys thinking as you approach a short field?

I'm not even sure what it means Jim. What if the wind is blowing 20 kts?

I'm with zane on this one. I don't get it. I read 'brisk walk rate of closure' and think, theres no way i can walk that fast.

It made no sense to me either until Jim showed me. I like the technique as it allows a faster approach, with the slow down period much closer to the runway. I don't use it 100% of the time but I do find it much more comfortable and relaxing at normal airport operations. In cases where performance landing or clearing obstacles is in play I resort to other methods. But I'm still learning new things all the time. Jims techniques on paper I had a hard time following, in real life they make great sense once he shows you exactly what, why and how. I'm sure next time Jim and I get together he will have even more to expand on.


Sent from my iPhone using Tapatalk

I'll take a picture out of a helo aircrew training manual for VMC approach later today. That might help explain what Jim's talking about. Thanks to primacy, the apparent rate of approach method is my primary. The key is to know how slow you can get before you run out of energy for the flare. That's best discovered at altitude, then tweaked in small increments in ground effect.

Zane,

With a 20 knot headwind, we could have 20 knots more airspeed to have the same apparent brisk walk rate of closure. This apparent rate does not change much, regardless of airspeed, until close. What actually happens is that we touch down with much less ground speed, even zero. We have to be careful to protect the nose gear and to avoid going backwards. I only touched down backwards once. It was in a Champ. It was scary and I had to wait for help to get tied down.

Thanks for the question, but do you notice the increase in the apparent brisk walk rate of closure when you get close? Do you slow down when you see this apparent rate increase? I really think more pilots do than think they do.

Jimmy (only my Mom and the Army call me that )

I think a lot of us use this method and don't realize it. Personally, when I'm landing I only look at my airspeed when setting my first notch of flaps. After that it's all feel. But I have been really noticing that when I watch my landing spot it does seem like a brisk walk. I slow down all the way until I land, I don't set a speed and ride it in.
I think the term "apparent brisk walk rate of closure" just goes over a lot of our heads.

contactflying wrote:... do you notice the increase in the apparent brisk walk rate of closure when you get close? Do you slow down when you see this apparent rate increase? I really think more pilots do than think they do.

Flying the pattern at a decent maneuvering speed, as to retain good control authority and be able to "cut through the gusts", gradually slowing on final to good and slow crossing the fence .......apparently I've been flying this "apparent rate of closure" approach for years, I just didn't have a fancy name for it.
I think a lot of pilots fly this way, but like me they haven't thought too much about it as it seems very natural, and unless they're a military helo pilot they haven't assigned a name to it.

Hotrod180,

Yes,I think this apparent rate enters the brain and pilots respond. The give away with you, in another thread,was when you mentioned continuously cranking in more up trim all the way down. I was young and vigorous when I flew C-180 quite a bit and just hauled back more.

It is evident, even in the videos, that pilots are perceiving the apparent rate of closure because airplane doesn't appear to close with the camera faster than a brisk walk even when close. I have done a lot of instructing from the ground using apparent rate.

Thanks for the comments.

Contact

I'm familiar. I think my issue is the terminology.

I could say don't stabilise airspeed, stabilise how fast you seem to be going. Or slow down like you're coming to a stop sign but you're going to make it a rolling stop. The important thing is that pilots realize this very helpful visual cue is out there, whatever we call.

Jim,

The problem I see with this is that you've never (at least on this website that I've seen) actually articulated what it is you're talking about. I for one have no idea what you're describing, though I suspect it is pretty much what many of us use during short field approaches.

Please try to DESCRIBE what you are talking about, not just keep saying "the brisk walk approach...." Maybe an Army aviator understands what you are describing, but the rest of us apparently don't.

Thanks,

MTV

"

Mike,

From 500 feet or higher, we appear or seem to be moving toward a distant target slowly. If we look down at our left main tire and count telephone poles, we appear to be moving much faster. While our speed is the same, we appear to be going faster when our field of view is limited. This same phenomenon occurs as we approach closer to and lower to the numbers. If we are on a stabilized approach at a constant airspeed, the speed at which we appear to approach seems to speed up the closer we get. This is if we are looking outside at objects and the numbers and not looking at the airspeed indicator, as during an instrument approach. By the time the numbers go under the cowl, we appear to be closing with the numbers very fast. If we round out and look on down the runway, the speed appears to slow back down to the original rate we were going before.

The trick is to use this incorrect rate, this apparent rate, to alert us to the fact we are going really too fast for a really short field or too fast for a fairly short field. By maintaining or stabilizing this incorrect rate, this apparent rate, we actually slow down over the last quarter mile and last 500 feet altitude of an approach so as to arrive at the fence with no need to round out. There is no need to round out because we don't need to slow vertical speed and forward speed. We have already done that by the gradual speed reduction caused by maintaining a constant apparent closure rate. Our airspeed will be slowing during this process. Our rate of descent will increase requiring more power. More power will force more air over the wing. Our pitch attitude will gradually increase from 500 feet and a quarter mile, and then increase a little more rapidly from short final on in. Our power will gradually increase to maintain the stable descent rate and then increase more rapidly as we get really close.

This is not to say we don't still control descent with power as needed and apparent forward speed (apparent rate of closure) with elevator as needed. It is just a normal power/pitch approach. The only difference is that pitch controls apparent speed, not a stabilized 1.3 Vso.) Wait! There is an important safety difference: we don't get really slow, and with a tailwind probably go behind the power curve, until really close and entering ground effect. Yes! In a tailwind this approach can safely be made to less than Vso on touchdown with a lot of pitch, a lot of power, and no bounce.

Thanks for the questions Mike, I think this visual phenomenon is or could be useful for the kind of flying a lot of these guys do. I want to do anything I can possibly do to explain it. That includes flying with you, Cary, and other instructors and pilots if possible.

Jim

Mike,
I forgot to mention there is a chapter on this approach in the book. Click below.
Thanks again,
Jim

I didn't have time to add this yesterday. Jimmy's last big entry is a much better descriptor. This thing isn't as explanatory as I remember, but it's not one of the tasks you re-read often after initial qualification.

I think a lot of the trouble some have with your tutorials is your phraseology.
"Apparent brisk walk rate of closure", "kinetic pressure of airspeed", "dynamic proactive", and some others I can't recall right now all kinda leave me saying "huh?".

Quoting Hotrod 180, "I think a lot of the trouble some have with your tutorials is your phraseology."
"Apparent brisk walk rate of closure", "kinetic pressure of airspeed", "dynamic proactive", and some others I can't recall right now all kinda leave me saying "huh?"

This is my perhaps crude attempt to change orientation from a speed we read off a gauge to a visual cue that will help us slow down gradually before the desired touchdown spot. With pressure airspeed I am going for the illusion that this fluid stuff called air provides the lift when it goes over the wing rather than a V this or V that that means nothing to my feeble brain. Most balance issues, like riding a bike or controlling an airplane, are dynamic. We can choose to remain static and then react to variable conditions or we can choose to move. We're better when we move. Finally we can be proactive. Pro means before and active means moving. I like moving. Proactive control movement is getting ahead of the airplane and causing movement we control rather than waiting and reacting to movement we do not control. Going back to balance, we are better when we control the movement. Once the broom balanced on our hand begins to move, we are behind and trying to catch up until we can't catch up and the broom topples. We have to apply dynamic and proactive hand movement to get ahead of that and actually control things. This is called balance.

I would submit that my terminology is no more complicated than sanctioned aviation terminology like exceeding the critical angle of attack. What is the critical angle and how does it get exceeded. Lots of confusion and questions here too. When we use common but complicated terminology we cause our students to zone out. They can say it and kinda remember what it means, but it doesn't get their attention. It doesn't make them think.

I apologize for the phraseology. I also very much hope it has made you think.

Regardless, thanks for the questions, criticism, and comments. They are critical to two way communication and appreciated. Communication happens when the picture in mind A becomes the picture in mind B. I will strive to see what you write, say, or demonstrate. I hope you will strive to see what I write, say, or demonstrate. I hope we get a chance to fly together sometime. We're better when we move. That said, as an instructor I mostly talk. You guys are beginning to worry me.

Apparent rate of closure approachs work extremly well in helicopters, where you are both descending and slowing all the way down final. As an ex army aviator, this was drilled into my head. In an airplane, it may work if your stall speed is slower than the ¨brisk walk¨ apparent rate of closue. In a helicopter, you basically only look at your desired touch down point. In airplanes if you only keep the desired touch point coming at you at apparent rate of closure of a brisk walk, you are well likely to stall on short final. If you look a lot further down the run way, you have changed your refernce and the apparent rate of closure will also change.

gdaniels,

Good point. In airplanes we lose sight of the numbers and have to look on down the runway before getting too slow. Also what is all that slow flight and stall practice for? I hope it's not to learn how to stall on takeoff or short final. I hope we learn to recognize the pitch attitude, relative wind, stick position and sloppiness, lack of buoyancy of mush and near stall, etc. Apparent rate is a helpful visual cue, not a replacement for all that pilot stuff.

Off topic, what did you fly in the Army and where?

Jim

I've never even been in a helicopter, but I'm not sure that applying helo approach tactics to flying a fixed wing airplane is necessarily the best way to go. The army's training tactics for the L19 Birddog, U17 Skywagon, or the L20/U6 Beaver might be more appropriate for most of us.