Wing down during final approach.
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I'm a 'crabber' but I flew gliders for decades before going to the dark side. It's just natural for me to crab the approach. Having said that one of my club pals poles 757's as the day job and he uses wing down. Says you know if you have enough control authority that way. Never tried it other than slipping on finals to loose a bit of height. As an aside, how many times have you been in a howling xwind at 200' and by the time you are flaring it's down to a gentle breeze? I've sat beside wing down pilots on xwind approaches and it seems like a whole lot of work to me. But hey, whatever you're comfortable with.
Engine/yoke for speed on instrument approaches: an engine man myself, find it more natural to keep on the glideslope with the throttle. The aircraft is trimmed out and a trickle of extra or less power is much easier to control than chasing the needles with the yoke. IMO of course. If you're having to make power adjustments of more than 100 rpm then you haven't set yourself up properly in the first place.
Engine/yoke for speed on instrument approaches: an engine man myself, find it more natural to keep on the glideslope with the throttle. The aircraft is trimmed out and a trickle of extra or less power is much easier to control than chasing the needles with the yoke. IMO of course. If you're having to make power adjustments of more than 100 rpm then you haven't set yourself up properly in the first place.
One more vote for crab on final. Never liked the slip method in a light aircraft, and it just isn't done on a large aircraft...at least none that I have flown.
There are several drawbacks to the "Kick off Drift" school.
a) it requires a measure of fine judgement at the last minute - which has wrecked the confidence of many a budding aviator.
b) get it wrong - or forget to apply into wind aileron on a swept wing jet - and you can be left in a highly vulnerable situation as many dramatic videos testify.
c) have you ever sat in Row 40 while someone applies an agricultural amount of boot at the last minute?
The Boeing autopilot initiates its slip from about 500' and I believe has been demonstrated up to 35k or so across. The human pilot is better advised to leave the procedure to about 100' by which time the wind is more representative of that on the runway. It is vital that the into-wind aileron is maintained into the landing roll to ensure runway adhesion and lift dump deployment.
Crabbing into the flare may work for little aeroplanes in light Xwinds but have watched it go wrong too often. There is no doubt in my mind that slip in the last couple of hundred feet leads to a more consistent and polished outcome.
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Crabbing into the flare may work for little aeroplanes in light Xwinds but have watched it go wrong too often. There is no doubt in my mind that slip in the last couple of hundred feet leads to a more consistent and polished outcome.
. I've flown crabbed approaches for the last 30 years in xwinds that have been very naughty at times and never had any problems at all. I sit in awe at the judgment required to do a slip approach, to me a crab approach is a no brainer, I do them without any conscious thought.There's no right or wrong way, just the way that you prefer. The end outcome needs to be a safe landing, if you are making safe xwind landings consistently then everyone is a winner.
There's no right or wrong way, just the way that you prefer.
In my experience the slip technique is much more easily mastered than the other and is particularly suited to swept wing aircraft - although effective in all.
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Foxmouth
I disagree !!! You are presuming a constant which is rarely the case in strong crosswinds with gusts up draughts or down draughts !
I disagree !!! You are presuming a constant which is rarely the case in strong crosswinds with gusts up draughts or down draughts !
I will say I have flown many aircraft that I have been told "very dodgy in a crosswind" (e.g. Auster/ Tiger Moth/Leopard Moth), never had a problem myself using wing down, speaking after to the pilots that told me this, most used crab!
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Good morning gang....
Well, well this has turned out real well, three pages and everyone still friendly and no one has gone bonkers.
So it can be seen that thoughtful discussion about different methods of aircraft handling can be educational as we have going here.
The operative description is " Aircraft handling " which involves a broad spectrum of attitudes and manipulation of controls to produce a desired attitude.
I chose this subject because it is one which I knew every pilot here would have not only a preference for but a reason for their preference.
As we can gather from how this discussion is going either method of approach to landing will work, therefore the only difference is which method is best.......
With a bit of reflection on the subject we must come to the conclusion that generally speaking at some point in the approach, landing in a strong cross wind crossed controls will be needed.
For me I try and visualize why I don't use the side slip method of maintaining track on a cross country and from that determination I plan my use of the flight controls during my landing approach.
Anyhow ...great job gang everyone is polite and thoughtful.
I was going to start a new discussion on how to judge height height above the runway for the flare....but decided to do this subject....
...and someone here might be able to retrieve my ideas on the judging height above the runway from some years ago.
I am getting old now but I do still get pleasure from sharing the lessons I learned during my career as a pilot and should do so before I become a complete mindless idiot.
Well, well this has turned out real well, three pages and everyone still friendly and no one has gone bonkers.
So it can be seen that thoughtful discussion about different methods of aircraft handling can be educational as we have going here.
The operative description is " Aircraft handling " which involves a broad spectrum of attitudes and manipulation of controls to produce a desired attitude.
I chose this subject because it is one which I knew every pilot here would have not only a preference for but a reason for their preference.
As we can gather from how this discussion is going either method of approach to landing will work, therefore the only difference is which method is best.......
With a bit of reflection on the subject we must come to the conclusion that generally speaking at some point in the approach, landing in a strong cross wind crossed controls will be needed.
For me I try and visualize why I don't use the side slip method of maintaining track on a cross country and from that determination I plan my use of the flight controls during my landing approach.
Anyhow ...great job gang everyone is polite and thoughtful.
I was going to start a new discussion on how to judge height height above the runway for the flare....but decided to do this subject....
...and someone here might be able to retrieve my ideas on the judging height above the runway from some years ago.
I am getting old now but I do still get pleasure from sharing the lessons I learned during my career as a pilot and should do so before I become a complete mindless idiot.
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So you have mastered the fine judgement required. You do not say whether you are involved in training - or indeed what type you fly.
In my experience the slip technique is much more easily mastered than the other and is particularly suited to swept wing aircraft - although effective in all.
In my experience the slip technique is much more easily mastered than the other and is particularly suited to swept wing aircraft - although effective in all.
). I'm just a common or garden club pilot. I dare say the majority of posters here are in the same category as me and do not fly exotica, much as I /we would probably like to. As I say, one of my flying buddies flies Boeings and he swears by the slip method. It works for him. Crab works for me, although I'm easily swayed if bought beer.
As Chuck says, the last bit of a crab landing is a slip landing anyway, so what's the difference? I just hold off the slip longer than you do.
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Foxbat
Really sorry with the typo error totally unintentional and no malice whatsoever intended
Pace NB I fully understand the principal but ask you if that is the case why it is not the predominant method used in GA or professional flying?
There is more than minimal extra drag cross control the problem being the upset and loss of control if you need to dump it quickly.
I have used the crab method in 40kts 90 degree winds into Denham in a twin (that was the absolute limit)
Pace
Really sorry with the typo error totally unintentional and no malice whatsoever intended
Pace NB I fully understand the principal but ask you if that is the case why it is not the predominant method used in GA or professional flying?
There is more than minimal extra drag cross control the problem being the upset and loss of control if you need to dump it quickly.
I have used the crab method in 40kts 90 degree winds into Denham in a twin (that was the absolute limit)
Pace
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I have used the crab method in 40kts 90 degree winds into Denham in a twin (that was the absolute limit)
Again, shows lack of understanding of method, one of the beauties of wing down is that it is easy to compensate for changing conditions, you just vary the amount of wing down - how do you do that with crab?
Last edited by thing; 30th Jan 2014 at 15:58.
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The reality is that if you change pitch, you are going to have to change power to keep the equation in balance. Since autopilots control glodeslope with pitch when coupled in approach mode, it is obviously possible for the human to do the same. It is also the recommended procedure when flying large airplanes. If autothrottle equipped, power controls airspeed.
With one exception, I use the same technique in my 185 or in the jets I fly. The one circumstance where I use power to control rate of descent is when I am slow ~1.1 or 1.2 Vso on an approach to a short strip in the 185. Power actually helps control both descent and airspeed in that circumstance, because if the tendency is to go slow, power is necessary and if the rate of descent needs adjustment, power needs an adjustment. In order for this to work, one has to be slow. I also adjust my approach speed according to my weight for a more accurate reference to actual Vso. My empty weight is 1840 compared to a 3525 GW, so adjusting approach speed can make a difference in the rollout distance.
Quote:
(and glideslope is pitch, not power)
At the risk of starting another "Stick and Rudder" thread, I have to ask what you mean by "glideslope is pitch, not power"? Is this something peculiar to an Autopilot approach?
I'm not an IFR pilot but am fortunate to have a large under-utilised "international" airport in the vicinity who are open enough to have spam cans practising ILS approaches without the associated fees so have occasionally taken some foggles to practice an ILS approach - "just in case".
In my experience, it's exactly the opposite - glide slope is power, not pitch: I say this because I'll adjust the pitch (and trim) for my approach speed and then look to follow the glide slope using power..... I find if I'm too high on the slope and lower my pitch, I gain speed. If I'm low and increase my pitch, I lose speed.....
(and glideslope is pitch, not power)
At the risk of starting another "Stick and Rudder" thread, I have to ask what you mean by "glideslope is pitch, not power"? Is this something peculiar to an Autopilot approach?
I'm not an IFR pilot but am fortunate to have a large under-utilised "international" airport in the vicinity who are open enough to have spam cans practising ILS approaches without the associated fees so have occasionally taken some foggles to practice an ILS approach - "just in case".
In my experience, it's exactly the opposite - glide slope is power, not pitch: I say this because I'll adjust the pitch (and trim) for my approach speed and then look to follow the glide slope using power..... I find if I'm too high on the slope and lower my pitch, I gain speed. If I'm low and increase my pitch, I lose speed.....
With one exception, I use the same technique in my 185 or in the jets I fly. The one circumstance where I use power to control rate of descent is when I am slow ~1.1 or 1.2 Vso on an approach to a short strip in the 185. Power actually helps control both descent and airspeed in that circumstance, because if the tendency is to go slow, power is necessary and if the rate of descent needs adjustment, power needs an adjustment. In order for this to work, one has to be slow. I also adjust my approach speed according to my weight for a more accurate reference to actual Vso. My empty weight is 1840 compared to a 3525 GW, so adjusting approach speed can make a difference in the rollout distance.
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I have used the crab method in 40kts 90 degree winds into Denham in a twin (that was the absolute limit)
We never know what conditions may face us some day, therefore we must strive to learn to handle an airplane to the limits the airplane can be operated.
The above can and will present its self if you fly long enough.
Many years ago I was faced with an approach and landing with a cross wind of 90 degrees at fifty knots with ground visibility of zero zero in blowing snow in a DC3. The landing was successful.
I feel your examples will fall on deaf ears...
But there will always be those who can hear.
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Scotbill:
The 767 is fairly advanced. The 727, CE-500, Westwind 2, C-130, DC-8, Twin Otter and the Classic 747's (10 kt autoland XW limit, BTW) that I have flown didn't/don't slip on final when coupled. 767 slip is not very dramatic either, as some crab is used in combination.
Kicking it out in the flare is a fact of life with most airplanes. A crab in an approach to a gusty mountain airport makes for a much more controllable and comfortable approach compared to attempting the same with a slip. I think you'll find that most high density altitude, spam can, mountain pilots will agree with my assessment.
The 767 is fairly advanced. The 727, CE-500, Westwind 2, C-130, DC-8, Twin Otter and the Classic 747's (10 kt autoland XW limit, BTW) that I have flown didn't/don't slip on final when coupled. 767 slip is not very dramatic either, as some crab is used in combination.
Kicking it out in the flare is a fact of life with most airplanes. A crab in an approach to a gusty mountain airport makes for a much more controllable and comfortable approach compared to attempting the same with a slip. I think you'll find that most high density altitude, spam can, mountain pilots will agree with my assessment.
I use crab by default (SEP, tricycle gear) but combine it with wing down if the crab angle is getting silly due to a large xwind component.
Was never taught to do so (nor was ever taught wing down in isolation) - its just something that has evolved in my flying over the years.
Was never taught to do so (nor was ever taught wing down in isolation) - its just something that has evolved in my flying over the years.
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Another thought.....
If we use the side slip during the final approach segment of the approach and landing and the X/wind is strong we are forced to use significant slip to track the landing path......and thus more power will be needed to maintain your glide path...
....so by slipping to early you have destabilized your approach.
If we use the side slip during the final approach segment of the approach and landing and the X/wind is strong we are forced to use significant slip to track the landing path......and thus more power will be needed to maintain your glide path...
....so by slipping to early you have destabilized your approach.
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I was taught the crab method during my PPL, then post PPL I flew with a family member (75 skipper and GA Instructor) who can't advocate the cross-control method strongly enough. Notice I avoided the use of the words side-slip or wing-down; when I thought of the approach in these terms I found it very difficult to master and found myself hugely over controlling the aircraft both with rudder and aileron, then the approach became extremely uncomfortable!
The key to making the approach comfortable I found was a fine balance of sufficient rudder and aileron combination, which except for in very strong winds led to approaches with wings level (or very nearly so) and the nose pointing directly down the centre-line. A very comfortable position to be in if you ask me.
Feeding cross-controls in gradually throughout the final approach I find works best for me and gives me a great feel for how much control is going to be required and keeps the aircraft stabilised on the centreline of the runway from turning final to touching down and the subsequent roll-out. I find it also helps negate any nasty surprises from low-level windsheer as the control inputs required to correct it are so much smaller.
Just my humble opinion as a relatively low hour pilot.
The key to making the approach comfortable I found was a fine balance of sufficient rudder and aileron combination, which except for in very strong winds led to approaches with wings level (or very nearly so) and the nose pointing directly down the centre-line. A very comfortable position to be in if you ask me.
Feeding cross-controls in gradually throughout the final approach I find works best for me and gives me a great feel for how much control is going to be required and keeps the aircraft stabilised on the centreline of the runway from turning final to touching down and the subsequent roll-out. I find it also helps negate any nasty surprises from low-level windsheer as the control inputs required to correct it are so much smaller.
Just my humble opinion as a relatively low hour pilot.
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I was most pleased to see a post again from Chuck as I have both enjoyed reading his contributions and posts over the years.
To a hobby pilot, it's always seems interesting that this still a subject of much debate. In training some years ago, I was taught both methods.
In the cirrus I now fly, the poh is clear at least in advising pilots to avoid 'prolonged slips ' on final approach.
I have to admit I find crabbing in most comfortable but I start to straight with rudder and get into wing aileron down just a bit before I enter the flare. This means that I have everything just beginning to move in the right directions and I continue this into flare and hold off. I found that especially in strong crosswinds it made my landings smoother.
I think that the slip is easier when less experienced, as the final approach picture looks more familiar in the last 300 feet. At least it did for me.
I am reading stick and rudder at the moment.
To a hobby pilot, it's always seems interesting that this still a subject of much debate. In training some years ago, I was taught both methods.
In the cirrus I now fly, the poh is clear at least in advising pilots to avoid 'prolonged slips ' on final approach.
I have to admit I find crabbing in most comfortable but I start to straight with rudder and get into wing aileron down just a bit before I enter the flare. This means that I have everything just beginning to move in the right directions and I continue this into flare and hold off. I found that especially in strong crosswinds it made my landings smoother.
I think that the slip is easier when less experienced, as the final approach picture looks more familiar in the last 300 feet. At least it did for me.
I am reading stick and rudder at the moment.
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Making the correction before the flare starts is good echobeach!
Its trying to compensate for drift during the flare where it tends to go horribly wrong. There is loads of you-tube footage where crabbed approaches have gone horribly wrong but none that I have ever seen from pilots who make a habit of aligning the nose of the aircraft down the centreline prior to touchdown!
Its trying to compensate for drift during the flare where it tends to go horribly wrong. There is loads of you-tube footage where crabbed approaches have gone horribly wrong but none that I have ever seen from pilots who make a habit of aligning the nose of the aircraft down the centreline prior to touchdown!
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sapco
you don't see many you tube videos of the slip method because usually you tube videos are in extreme conditions. extreme usually requires the crab.
use what you feel safest with. after all, in a one pilot plane you are the boss.
you don't see many you tube videos of the slip method because usually you tube videos are in extreme conditions. extreme usually requires the crab.
use what you feel safest with. after all, in a one pilot plane you are the boss.
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As I don't feel competent enough to comfortably handle a crosswind landing with just one of the two techniques, I tend to use a mixture (in the rare occurrences where the need arises for me). Slightly wing-down-cross-control but mostly crab in the final approach which ideally changes to more wing-down-cross-control and no crab during the flare and touchdown. Granted, not a perfect landing if I fail to complete the abovementioned transition before the airplane completes its transition from airborne to aardvark, but it has never come to an appreciable gear abuse let alone a runway excursion.
Cross-controlling all the way just feels awkward for me and doesn't suit my laziness. In addition, even with my humble experience I can second the assertion in one aviation book I've read: the wind mostly changes near the surface anyway, therefore even with the cross-control method one has to juggle with rudder and ailerons in the flare to get it right, so why labor earlier than necessary?
Cross-controlling all the way just feels awkward for me and doesn't suit my laziness. In addition, even with my humble experience I can second the assertion in one aviation book I've read: the wind mostly changes near the surface anyway, therefore even with the cross-control method one has to juggle with rudder and ailerons in the flare to get it right, so why labor earlier than necessary?
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Actually no they don't glendalegoon, you'll be in total control all the way if you fly the cross control technique correctly. Some folk here are describing it at as side slip manoeuvre but it's not as extreme as that. It works very nicely, even in extreme conditions, and this is the reason you don't see the technique going wrong!