Why stall it?

Since we're talking about the dangers and benefits of different approach speeds, compared to a normal approach, whats the most you have increased your approach speed due to heavy icing conditions?
 
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flyingron said:
Presumes you have a stall horn, but even then it's a bit inaccurate.

That's better... here's what the FAA says:

This maneuver demonstrates the flight characteristics and degree of controllability of the airplane at its minimum flying speed. By definition, the term “flight at minimum controllable airspeed” means a speed at which any further increase in angle of attack or load factor, or reduction in power will cause an immediate stall. Instruction in flight at minimum controllable airspeed should be introduced at reduced power settings, with the airspeed sufficiently above the stall to permit maneuvering, but close enough to the stall to sense the characteristics of flight at very low airspeed—which are sloppy controls, ragged response to control inputs, and difficulty maintaining altitude. Maneuvering at minimum controllable airspeed should be performed using both instrument indications and outside visual reference. It is important that pilots form the habit of frequent reference to the flight instruments, especially the airspeed indicator, while flying at very low airspeeds. However, a “feel” for the airplane at very low airspeeds must be developed to avoid inadvertent stalls and to operate the airplane with precision.
​
Neither MCA nor stalled is where you want to be at landing.
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Thanks to both of you, that helped clear it up some for me.
 
dmspilot said:
We've gone from a hypothetical discussion on whether a "full" stall is the correct way to teach someone how land or whether it can be "a couple knots" above stall ... to criticizing other pilots for landing 20 knots too fast and wheelbarrowing and running off the ends of the runways. It makes me wonder why I bother participating in a discussion when so many feel the need to attack straw men and insult others.
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I'm one of those guys who used to instruct, and am now a guy that gets to fix busted airplanes. What do you think I--or anyone else--should think about guys who land 20 knots too fast and run off the runway? Or their instructors who taught them that sort of landing? Is aviation the sort of area where nobody can be held to account for their decisions or actions? Where there are no losers so that nobody's feelings get hurt?
 
Dan Thomas said:
I'm one of those guys who used to instruct, and am now a guy that gets to fix busted airplanes. What do you think I--or anyone else--should think about guys who land 20 knots too fast and run off the runway? Or their instructors who taught them that sort of landing? Is aviation the sort of area where nobody can be held to account for their decisions or actions? Where there are no losers so that nobody's feelings get hurt?
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What you have failed to realize is that this thread was never about people who land 20kts fast and run off the runway. That was a red herring introduced by some who have difficulty following the substance of the discussion.
 
Cooter143 said:
What you have failed to realize is that this thread was never about people who land 20kts fast and run off the runway. That was a red herring introduced by some who have difficulty following the substance of the discussion.
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Perhaps, but I think it was insinuated in one or more posts that a pilot should be free to choose whatever speed desired when landing, conventional wisdom and commonsense be damned.
 
N659HB said:
Perhaps, but I think it was insinuated in one or more posts that a pilot should be free to choose whatever speed desired when landing, conventional wisdom and commonsense be damned.
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Can you point that post out? I honestly don't see it. If it was my post I'd like to know.
 
rykymus said: There are many ways for me to land my plane, some of them safer than others. But there is no one way that is right every single time, as the conditions are always changing. It's about understanding the dynamics, yes, but it is also about 'feel'. That became obvious to me in the later stages of my training, when I was being allowed to fly my plane from my training airport to my home airport each day. The tower was constantly giving me different entries, extending legs, asking me to get down quick for faster traffic on approach, etc... I realized that following the 1,2,3 steps that I was originally taught to land the plane did not work in all situations. The same is true with getting the stall horn chirping. You need to be able to land the plane safely at just above stall speed, and at 10-20 knots above it. Getting too locked into a 'standard' method of doing things is a recipe for disaster, IMHO.
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I think this was where it started, and FastEddie mentioned Cirrus pilots landing at 80 knots in another post. Sorry I couldn't quote properly.
 
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Landshark said:
Since we're are talking about the dangers and benefits of different approach speeds, compared to a normal approach, whats the most you have increased your approach speed due to heavy icing conditions?
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Not sure, I've only landed once in heavy icing and I kept the speed up to maintain controllability but don't remember how much. Landing 20kts fast would have been very doable on this occasion though.
 
N659HB said:
I think this was where it started, and FastEddie mentioned Cirrus pilots landing at 80 knots in another post. Sorry I couldn't quote properly.
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Thanks. I didn't read that as advocating a 20+ knot approach speed window, but rather accentuating flexibility and good judgement rather than blindly following a single method. 20kts over is probably excessive but there may be a need to be comfortable with landing fast, and I think that's his point.
 
Cooter143 said:
Thanks. I didn't read that as advocating a 20+ knot approach speed window, but rather accentuating flexibility and good judgement rather than blindly following a single method. 20kts over is probably excessive but there may be a need to be comfortable with landing fast, and I think that's his point.
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I recall I brought that up as an extreme case, one that results in about 78% more energy to be dissipated compared to a 60 kt "full stall" Cirrus landing.

And it's not exclusive to Cirrus pilots. I watched a Bonanza come in fast without flaps and land fast and use pretty much every inch of Copperhill's 3,500' runway. I asked him about why no flaps, and he told me he just didn't like 'em. These may seem like extreme cases, but honestly they're not all that rare.
 
FastEddieB said:
I recall I brought that up as an extreme case, one that results in about 78% more energy to be dissipated compared to a 60 kt "full stall" Cirrus landing.

And it's not exclusive to Cirrus pilots. I watched a Bonanza come in fast without flaps and land fast and use pretty much every inch of Copperhill's 3,500' runway. I asked him about why no flaps, and he told me he just didn't like 'em. These may seem like extreme cases, but honestly they're not all that rare.
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I was referring to rykymus' post.....I don't spend much time around GA airports but twice recently I had a few minutes and walked out to see someone come in to land. The first was a Cirrus dropping off a pax and he porpoised halfway down the runway but no damage that I could tell. The other was a Cessna and he held it off about 5' above the runway until it slammed down hard. Also no damage that I could see but I was surprised. I recognized the plane later as someone I had flown with and he had landed almost that bad with me in it. I guess we could just say there are lots of substandard pilots and some have the money to buy more airplane than they can safely handle. Some aircraft don't allow for sloppy flying.
 
Cooter143 said:
I guess we could just say there are lots of substandard pilots and some have the money to buy more airplane than they can safely handle. Some aircraft don't allow for sloppy flying.
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Lots of Cirrus fatals where excess speed on touchdown was at least a contributing factor. Hard to think of any where not enough speed on touchdown was a contributing factor.
 
I'm doing 60 over the fence. 80 is almost as fast as pattern speed in my 152. 80 over the fence would be nuts and I assume, float quite a bit.

Since my plane cruises at 95, the difference in feel between 60 and 80 is very large. Maybe if you're in a plane that cruises at 160, the the difference in feel between 60 and 80 would be much less. The outcome could be just as bad though.

There was this phenomenon that I read about and have experienced it somewhat myself to. I forgot what it was called. It detailed driving for long periods of time at high speed on the highway. When it comes time to slow down for the exit and turn, what is perceived as a normal speed is actually much faster in reality and the driver runs straight off the road, unable to make the turn. The driver becomes acclimatized to the higher speed and anything else would feel slow.
 
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FastEddieB said:
Lots of Cirrus fatals where excess speed on touchdown was at least a contributing factor. Hard to think of any where not enough speed on touchdown was a contributing factor.
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Not a stats guy, but I'm sure there plenty of accidents attributable to getting too slow.

To play along with you're reasoning though, we actually have to find the accidents caused by landing at or just above the stall horn and compare those who "stall" too early before touchdown to be a relevant argument.
 
Cooter143 said:
Not a stats guy, but I'm sure there plenty of accidents attributable to getting too slow.
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Fatal accidents from being too slow at touchdown? Find me one and we can discuss it.

Sure, you can get too slow and stall/spin in the pattern. I'm trying to narrow this back down to the actual landing, which was the topic

And I guess you could balloon to ridiculous heights and get too slow and drop in in hard enough to kill yourself, but even there I don't think the main problem is the speed.
 
FastEddieB said:
Fatal accidents from being too slow at touchdown? Find me one and we can discuss it.

Sure, you can get too slow and stall/spin in the pattern. I'm trying to narrow this back down to the actual landing, which was the topic

And I guess you could balloon to ridiculous heights and get too slow and drop in in hard enough to kill yourself, but even there I don't think the main problem is the speed.
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Ok, sidebar here. You have missed my point multiple times, and not responded to the posts where I've made it. You need to understand that you are assuming gross error on those who fly fast and no, or negligible error on those who would get slow. You need to have equal balances when judging the technique. You make the assumption that landing a few knots fast equates to opening the door to touching down at near cruise speeds, neglecting to consider how they got there. Why do you have to give an exaggerated example to make your point, but then act like it would be silly to assume that an equal error could be made in the opposite direction? Please respond because that is a critical point in obstructing the progress here.
 
Cooter143 said:
Ok, sidebar here. You have missed my point multiple times, and not responded to the posts where I've made it. You need to understand that you are assuming gross error on those who fly fast and no, or negligible error on those who would get slow. You need to have equal balances when judging the technique. You make the assumption that landing a few knots fast equates to opening the door to touching down at near cruise speeds, neglecting to consider how they got there. Why do you have to give an exaggerated example to make your point, but then act like it would be silly to assume that an equal error could be made in the opposite direction? Please respond because that is a critical point in obstructing the progress here.
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People aren't so much afraid of landing too fast. I think it would be more common that pilots afraid of getting too slow creep further away from the target speeds specified in the POH. So, carrying to much energy I think would be a more common problem. I don't think there is a winner or loser to this argument, especially when you assume no gross error either way.
 
Cooter143 said:
You make the assumption that landing a few knots fast equates to opening the door to touching down at near cruise speeds, neglecting to consider how they got there.
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It was meant as a sort of argumentum ad absurdum.

To show how far it can go. 21% more energy at touchdown doesn't get your attention? How about 78% more? AND IT SOMETIMES HAPPENS IN REAL LIFE!

But I think I've made the best case I can for my position, and anyone can go back through this thread - hardly the first on this topic - and reflect on my "body of work", so to speak. And then decide how fast they choose to land.

My work here is done.
 
Cooter143 said:
Thanks. I didn't read that as advocating a 20+ knot approach speed window, but rather accentuating flexibility and good judgement rather than blindly following a single method. 20kts over is probably excessive but there may be a need to be comfortable with landing fast, and I think that's his point.
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Now that I have re-read his post several times, I think he meant carrying 20 knots into the approach, but not the landing, and I think he clarified that in a follow-up post. I have under 200 hours, so I'm no expert, nor do I mean to come across that way, and I'm certainly not pointing fingers at anyone.
 
FastEddieB said:
It was meant as a sort of argumentum ad absurdum.

To show how far it can go. 21% more energy at touchdown doesn't get your attention? How about 78% more? AND IT SOMETIMES HAPPENS IN REAL LIFE!

But I think I've made the best case I can for my position, and anyone can go back through this thread - hardly the first on this topic - and reflect on my "body of work", so to speak. And then decide how fast they choose to land.

My work here is done.
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I am just trying to keep the discussion level so that the important points aren't being obscured. I don't mean to offend or be off putting but I am a bit of a stickler in sorting out the distractions and getting to the heart of the issue. As one last follow up, reductio ad absurdum should be used to bring light to a point that is being misunderstood, not the only means of argument itself. Otherwise, it begins to look like an evasion. At a bare minimum, if you insist on using it at least grant your opponent the same latitude. I think you made some good points, but reductio worked against you here. I'll post tomorrow and lay out the pros and cons as they were presented here and my take on them for anyone interested.
 
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exncsurfer said:
I don't think there is a winner or loser to this argument, especially when you assume no gross error either way.
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It doesn't need to get separated into winners and losers unless someone is clearly wrong. I don't totally agree/disagree with either way and I think preference is fine for most circumstances. I just want both sides argued on merits not absurdum. Eliminating all error would be the fairest way to argue it.
 
I'm not going to take time to read back through everything posted so my summation may not be totally accurate, but I'll try to cut through the fog and lay out what I saw as the pertinent points here. I really wanted to keep the discussion on track but didn't seem to have much success but the main thrust was finding support for either holding off the aircraft until it would no longer continue flying, or preserve some flying speed and use it to fly gently down to the runway. I am a proponent in most circumstances of preserving flying speed so I may have been a little biased.

STALL IT PROs:
1. Excess energy can be an issue if other factors are ignored (like runway length, density altitude, approach path, etc). It increases proportional to the square of velocity, so a little goes a long way. This is the single best point raised in my opinion but the point was mostly lost by those who couldn't seem to acknowledge the difference in 2kts and 20 kts. The slippery slopers kind of killed the discussion in my opinion.
2. FAA sets a standard and this technique definitely meets the standard. I agree, if it can be done properly you shouldn't have any question that the examiner will be pleased.
3. You might need it in some circumstances so it's best to do it every time and hone the skills.
4. If something unforeseen goes wrong on the ground, slower is better.
STALL IT CONs:
1. Slow can put you in box that's tough to recover from. (This didn't get mentioned but I think it's valid). Over correcting on the flare at near stall speed can set up a high and slow which can be bad if not recovered properly. BTW, those have been some of my scariest moments as an instructor.
2. Less energy means less options. Getting down to MCA reduces your ability to correct for crosswind, gusts, or anything interrupting the landing.
3. Slow can severely impede go-around as a ready and viable option. It is more of a mindset thing, but many times it was brought up that you hold it off until the plane was "done flying". That doesn't foster a good go-around mindset in my opinion.
4. We never addressed floating eating up usable runway. Especially in gusty conditions, I would like to see some landing distance data regarding floating vs setting it down firmly and getting on the brakes. Short field, why do we do it the way we do for short field and why can't that be brought into the discussion? None of the run it off the end 20kts fast people addressed this.

I've run out of steam, so I'm not going to list out the other side the same way. But a couple of points to consider:

A toolbox of skillsets is necessary for safe flying. Being adaptable to the conditions is part of what makes it challenging and fun. I don't treat every landing the same and I don't treat a 5000' runway the same as a 1700' grass strip. I'm confused as to why the reasonable man approach didn't prevail here. Treat each landing as it's own challenge and don't neglect to read and understand the available information. It seems pretty straightforward to me. PTS don't require depleting all flying energy before touchdown and any decent pilot should be able to touch down somewhere between stall and bounce it off the runway fast and readily recognize the difference between the two. One last thing, in regards to checklist everyone seems to operate on the idea that you run them like you would in an airliner because someday you might move up to bigger and faster airplanes. But, in regards to landing, this idea was never brought up. The fact is, you don't land the bigger planes the same way and the proponents of stall it to land it appeared stuck in taildragger short field land. If that's all you fly, great, but there is a bigger world and most people operate elsewhere.

Those are my thoughts on the matter, hopefully this was helpful to someone.
 
Cooter143 said:
4. We never addressed floating eating up usable runway. Especially in gusty conditions, I would like to see some landing distance data regarding floating vs setting it down firmly and getting on the brakes. Short field, why do we do it the way we do for short field and why can't that be brought into the discussion? None of the run it off the end 20kts fast people addressed this.
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With any excess speed, the brakes are less than effective. I have changed way too many tires on flight-school airplanes when students or instructors have tried to fix a fast landing with brakes. That wing is still lifting, and any weight on it is taken off the tires and they skid and get flat-spotted or even blown out. Many are the times I've watched this happening, and the elevator isn't being pulled full-up to get more weight on the wheels. Resource management.

Airliners are another matter entirely. Their weight means that speeds have to be nailed. If the thing gets slow, it takes time to fix it, maybe too much time. I also often watch them float a long way down the runway. Airliners have reverse thrust, which most of us will never have. All we have are brakes that rely on weight and traction, which relies on the wing's lift being at a minimum, which relies on minimum speed. There's not much getting around that. That wing will still generate lift with the nosewheel on the ground. You'd need the nose pointed well down to stop all of it. Too many seem to think that once the wheels on the ground, the flight's over.

Nosewheels and their mechanisms suffer horribly with excess speed as well, especially since most of them haven't been dynamically balanced, and any shimmy just tears things up and the severe vibration can ruin everything else in the airplane, too. Excess speed costs in so many ways.

Short-field landings aren't the easiest thing, so many pilots learn just enough to get past a checkride, then forget all about them. It's part of the complacency that sets in. We don't do short-field landings as a matter of course on every landing unless we want to spend extra bucks on tires and brakes, but we could do soft-field landings a little more often. They're almost as short if they'de done right.

Too much speed in gusty conditions can lead to an inadvertent liftoff. The wing isn't stalled and is quite willing to respond. Got to keep flying the airplane and watch for that. Sometimes accidents happen because the conditions were beyond the pilot's abilities, and he should have aborted the landing and waited a bit, or gone somewhere else, or chosen another runway. Or stayed on the ground.
 
Airliners also have spoilers. Some POHs recommend lifting flaps to approximate that, but the effect seems minimal at best, at least with common electrical flaps. Heck, in the 182T, I can come to a complete stop before the flaps are done retracting from full. Those are the slowest flaps I've ever seen.
 
Cooter143 said:
4. We never addressed floating eating up usable runway. Especially in gusty conditions, I would like to see some landing distance data regarding floating vs setting it down firmly and getting on the brakes. Short field, why do we do it the way we do for short field and why can't that be brought into the discussion? None of the run it off the end 20kts fast people addressed this.
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This is all that I could find on the matter. Keep in mind that the extra distances vary by type and this chart was developed by Boeing for their airliners. Maybe someone can comment on how we can translate it to GA airplanes on a percentage basis. I found it in "Professional Pilot : Proven Tactics and PIC Strategies" and more information can be had in Boeing's D6-44247.

For every knot of excess airspeed, there was a 200 foot increase in float if the plane was allowed to bleed off airspeed in the flare and touchdown was at the normal speed. So 10 knots of excess airspeed resulted in 2000 feet of extra flare.

If the plane was flown onto the runway with an extra 10 knots, the increase in ground roll was only an extra 400 feet or 20 percent, the same percentage that we calculated earlier in the thread, due to the extra energy. This number includes the use of thrust reversers.
 

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Landshark said:
This is all that I could find on the matter. Keep in mind that the extra distances vary by type and this chart was developed by Boeing for their airliners. Maybe someone can comment on how we can translate it to GA airplanes on a percentage basis. I found it in "Professional Pilot : Proven Tactics and PIC Strategies" and more information can be had in Boeing's D6-44247.

For every knot of excess airspeed, there was a 200 foot increase in float if the plane was allowed to bleed off airspeed in the flare and touchdown was at the normal speed. So 10 knots of excess airspeed resulted in 2000 feet of extra flare.

If the plane was flown onto the runway with an extra 10 knots, the increase in ground roll was only an extra 400 feet or 20 percent, the same percentage that we calculated earlier in the thread, due to the extra energy. This number does not include the use of thrust reversers.
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Awesome, thank you. So the argument for holding it off til near stall to prevent going off the runway, is a faulty one (assuming the same energy state over the threshold). But, everybody know that because we've done short field landings. Plop it down and get on the brakes.
 
Oh I edited my post to state that the chart DOES include the use of thrust reversers. So it can't be compared directly to GA planes.
 
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Cooter143 said:
Awesome, thank you. So the argument for holding it off til near stall to prevent going off the runway, is a faulty one (assuming the same energy state over the threshold).
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There's the flare and hold-off, and then there's the round-out. The proper way to land is to get the power off when still 15 to 30 feet off the ground, get the nose coming up, let the speed bleed off so that the airplane arrives at the surface with minimal airspeed. The most common mistake I see happening is a steady approach speed all the way to the surface, where the pilot flares abruptly at about two feet. So it floats forever (which is where we get the hold-it-off-until-it-lands thing). Or it balloons. Or it gets landed flat, which has its own set of risks like wheelbarrowing or porpoising.

imagevf9.jpg


If it's done right, there's no float or anything else. And it really isn't hard to do this right.
 
Cooter143 said:
For both landings?
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Sorry for misleading you. Let me try to avoid confusing this any further because I try my best to avoid passing on bad info.

In the first landing, the extra 2000 foot landing distance is due to bleeding off the excess airspeed in the flare. The airplane actually flies 2000 feet farther, then touches down at the normal speed and has the normal braking distance. This can be compared to GA planes because we could do the same with an extra 10 knots.

In the second landing, the extra 400 feet is due to stopping with an extra 10 knots. The airplane is landed at the normal location but with an extra 10 knots. This extra speed requires an additional 400 feet to stop using regular brakes, speed brakes, and thrust reversers. Since typical GA planes only have regular brakes and do not have thrust reversers or speed brakes, it is not a fair comparison because the braking characteristics are totally different.

We need all 4 situations to be comparable to draw any conclusions about extra flaring distances relative to extra braking distances.

I was just hoping to provide an interesting extra data point until I realized that the inclusion of thrust reversers is a very important detail.
 
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Landshark said:
Sorry for misleading you. Let me try to avoid confusing this any further because I try my best to avoid passing on bad info.

In the first landing, the extra 2000 foot landing distance is due to bleeding off the excess airspeed in the flare. The airplane actually flies 2000 feet farther, then touches down at the normal speed and has the normal braking distance. This can be compared to GA planes because we could do the same with an extra 10 knots.

In the second landing, the extra 400 feet is due to stopping with an extra 10 knots. The airplane is landed at the normal location but with an extra 10 knots. This extra speed requires an additional 400 feet to stop using regular brakes, speed brakes, and thrust reversers. Since GA planes only have regular brakes and do not have thrust reversers or speed brakes, it is not a fair comparison because the braking characteristics are totally different.

We need all 4 situations to be comparable to draw any conclusions about extra flaring distances relative to extra braking distances.

I was just hoping to provide an interesting extra data point until I realized that the inclusion of thrust reversers is a very important detail.
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Plus a half-million pound difference in gross weight!
 
Oh yes of course, when I mention compare, that is with making adjustments for all the large and small details and at some point, adjustments cannot be made because they are so different. Thrust reversers and spoilers are 2 things that throw the comparison out the window.
 
Landshark said:
Oh yes of course, when I mention compare, that is with making adjustments for all the large and small details and at some point, adjustments cannot be made because they are so different. Thrust reversers and spoilers are 2 things that throw the comparison out the window.
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Certainly. Regardless of what one flies, it's all about energy management.
 
Cooter143 said:
Awesome, thank you. So the argument for holding it off til near stall to prevent going off the runway, is a faulty one (assuming the same energy state over the threshold). But, everybody know that because we've done short field landings. Plop it down and get on the brakes.
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Aerodynamic drag in the flare versus using wheel brakes. Which would dissipate the extra energy faster or in less distance? I'll take wheel brakes every time.
 
Landshark said:
Sorry for misleading you. Let me try to avoid confusing this any further because I try my best to avoid passing on bad info.

In the first landing, the extra 2000 foot landing distance is due to bleeding off the excess airspeed in the flare. The airplane actually flies 2000 feet farther, then touches down at the normal speed and has the normal braking distance. This can be compared to GA planes because we could do the same with an extra 10 knots.

In the second landing, the extra 400 feet is due to stopping with an extra 10 knots. The airplane is landed at the normal location but with an extra 10 knots. This extra speed requires an additional 400 feet to stop using regular brakes, speed brakes, and thrust reversers. Since typical GA planes only have regular brakes and do not have thrust reversers or speed brakes, it is not a fair comparison because the braking characteristics are totally different.

We need all 4 situations to be comparable to draw any conclusions about extra flaring distances relative to extra braking distances.

I was just hoping to provide an interesting extra data point until I realized that the inclusion of thrust reversers is a very important detail.
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But if they were used on both landings, one after floating and dissipating the energy and the other touching down fast and braking to lose the extra energy, they can be compared against each other right? By the way, brakes in GA airplanes are way more effective than most large airplanes in my experience. Braking often has to be done very gingerly in larger faster airplanes. So, I think the results would be exaggerated when extrapolated to GA aircraft.
 
Cooter143 said:
But if they were used on both landings, one after floating and dissipating the energy and the other touching down fast and braking to lose the extra energy, they can be compared against each other right? By the way, brakes in GA airplanes are way more effective than most large airplanes in my experience. Braking often has to be done very gingerly in larger faster airplanes. So, I think the results would be exaggerated when extrapolated to GA aircraft.
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Yes both airline landings can and were meant to be compared with eachother. What I was getting at is that the extra braking airline distance was only 20% as long as the extra airline floating distance, making the braking option much more attractive. Since the braking systems are so vastly different between GA and an airliner, I didn't want to use that 20% figure and infer that in a GA plane, the braking option was just as superior.

If anything, I thought the airliner would brake better because it has so many braking aids (thrust reversers, speedbrakes, spoilers, wheel brakes), whereas GA planes have few (wheel brakes, maybe thrust reversing prop if you're lucky). But if airliners brake less effectively (they are half a million pounds) than GA planes, that actually reinforces what the chart says and shows how much better it is to land the plane and brake hard.

I should say shorter, not "better", since landing fast could cause an accident.
 
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Landshark said:
Aerodynamic drag in the flare versus using wheel brakes. Which would dissipate the extra energy faster or in less distance? I'll take wheel brakes every time.
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IF you have the traction. If one bleeds off the speed before getting into ground effect (the round-out), there's no need for a lot of aerodynamic braking in the flare because there's so little speed left. And that's what one needs to do if the runway is slippery, like it often is here in the winter. Pilots who rely too much on brakes end up in the snowbank, whether they are driving or flying.
 
If you bleed off the excess speed in the round out, isn't that increasing the total runway requirement(roundout + flare + groundroll)? The scenario that I envisioned was coming over the fence with an extra 10 knots at the correct height. Whether you dissipate that extra speed in the round out before the flare or actually in the flare, I feel that Boeing says your going to fly an extra 2000 feet before you touchdown at normal speed. That extra 2000 feet will all be wasted runway passing below you.

edit:
After rereading your post, I do agree that you should bleed off excess speed before ground effect. Bleeding off excess speed in the decreased drag of ground effect will surely lead to longer floating distances. But the gist of my above post remains.
 
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