Centre Line

[I have control]

Can anyone help with some advice for how to hold the centreline on landing? Having never had a problem with it at all, I've suddenly and very annoyingly developed a tendency to drift a few feet left or right of centre on touchdown. This has happened after transitioning, from the Cub I learned to fly in to an Archer. I'm pretty sure it's a crosswind problem. The question is what technique to employ to keep me on the straight & narrow.

Thanks in anticipation

[HoldAlpha]

It sounds like you may just need to compensate that little bit extra for the crosswind.

Which technique are you using at the moment ?

[thjakits]

Hi Control,
it seems you have the same problem I had when I started to fly. You kind of KNOW you are drifting but at the very moment you are just locked - no think-react going on at all, just drifting to the edge touch and okay until the next time.

Next windy day go out and practise just landings AND takeoffs (if you have a long runway you might try to take off with LESS than full power and give the wind a chance to push you around a little so you can practise to hold against...)

On landing concentrate on nothing than centerline and a hanging wing. If you run out of aileron or rudder it is TOO windy!

Concentration is the game. If it does not work the first time, go again and again and again. Sooner or later it will click and you are back automatically controling drift!

Good luck,
3top :cool:

[Genghis the Engineer]

Sounds to me that you may be looking too close to the front of the aircraft, try looking further down the runway.

G

[I have control]

3top you have defined my problem perfectly, thank you. I will follow your advice.

[Kermit 180]

Good advice from Genghis. I can always tell when my students hit hard or dont track the runway centreline - theyre not looking at the end of the runway. For some of them it's natural anyway, as I drum it into them from the start. However, given a very windy day or a distraction in the circuit, and it can all turn to custard as their brain freezes like a possum in a car's headlight beam and forget where to look or become overloaded. Incidentally, I've never personally met a tail-wheeler who had problems tracking the centreline, its all part of trying to keep the thing straight and on the strip.

Kermie

[LowNSlow]

IHC, it could be that you were sitting in the centre of the Cub and you are sitting to the left in the Archer. Which side of the centre line do you usually land on?

It could also be that flying the Cub sitting in the centre with a stick is more instinctive than being offset with a junior 747 driver yoke in your left paw.

Also, in the Cub you think it and its done (relatively speaking). I've never found that with Mr. Piper's later products
:D

[Chuck Ellsworth]

Looking at the far end of the runway?

Kermit, have you ever been an Ag. pilot? If so how long do you think you would live if you looked at the far end of a one mile field to judge and maintain your height and position at two feet above the crop?

.............................................

:D The hardest thing about flying is knowing when to say no. :D

[Genghis the Engineer]

We were talking about maintaining the centreline during normal landings on a normal runway.

There are all sorts of situations (such as landing my slippery Canard on our 400m strip) when I'd be looking near the touchdown point, not the far end, and to hell with the elegance of it. But that wasn't the question.

G

[Noggin]

Try steering with the foot rests and keep the wings level with aileron.

[Chuck Ellsworth]

Genghis:

I also was addressing the subject of how to hold the center line while landing. What I was pointing out was one should not look to far foward, i.e. at the end of a long runway. That is why I used the crop dusting analogy, to point out that one can not acturately judge height or lateral position over the surface if your point of reference is to far away.

The inability to hold center line during approach and landing is one of the most frustrating shortcomings in flying skills that I find in the pilot pool.

I use a camcorder mounted at eye level when doing advanced training, after the flight I plug the camcorder into a T.V. and give the student a laser pointer. When the airplane starts to divert from the correct flight path and or the flare for the landing is incorrect I stop the picture and ask the student to show me with the laser where he/ she was looking and what they were thinking.

After we discuss why it has started to go wrong I start the camcorder again and stop it where ever a problem shows up.

This method of fine tuning errors in flying works extreemly well and saves a lot of guess work trying to determine where the student is looking and thinking at any point in an approach and landing.

I first used the Camcorder method of debreifing people during training on the water in large flying boats where attitude and rate of decent control during the landing is critical. It works so well that I now use it teaching precision flying and tailwheel training, especially wheel landings for judging correct flare height and attitude.

To sum up, where one looks is most of the secret in judging height and lateral position when landing. And looking to far ahead or to close in any given situation will result in inacurate flying skills.

I hope you now understand why I referenced crop dusting. :)

............................................

:D The hardest thing about flying is knowing when to say no. :D

[ 21 November 2001: Message edited by: Cat Driver ]

[thjakits]

Hi again control,

now that we are down to the problem, some more (anyone: correct me if I talk bull! It ´s a long time since I flew a fixedwing - I don´t remember why these damn things fly at all, when there are no wings turning to get you off the ground!!):

Good point: do not look immediatly in front of the airplane (whatever is or happens there you can´t avoid it anymore so don´t bother looking there....) it is kind of like driving a car (try it yourself - if you look right in front of your car you start to need the whole lane besides that you don´t see jack ahead. When you return to looking forward a REASONABLE distance - 300 to 600 ft should do - you notice you suddenly do not put any inputs in your steeringwheel to stay straight AND you are able to track where ever you want.)
Back into the plane: Try to line yourself up early so for practise make a longer then regular final (to start practise don´t try short-softfield-high obstacle landings....)

TRIM your plane to your final-speed and do not hesitate to add power if you need to stay on your glidepath (you can practise power-off landings when you´re back on "track"....)Try to keep very little or no pull at all on the stick or wheel.

Finally try to make your control inputs cotrolled: roll in slowly but firm. Jerking in and out will not give your plane time to react and you will never figure out, how much your inputs actually do.

another one: Make a list of all the points (copy your landing-checklist and then add the points noted here wherever you think they should go) and practise off the airport - somewhere open - 200ft - just make sure there is no restricted area and track a road at little more than approach-speed.
THen go back to the field and shoot landings.

And here the most important one:
Specifically for that training:
Do not be afraid to go around: Whatever the "guys" say, you are there to practise something, and smack it in on a "gone not so good approach" just tightens you up.
Actually I did lots of go arounds, even when it would have been an acceptable landing, why?
I tried to land centerline, when I drifted off, I would apply a little power to "fly" back to center, if it took to long I ran out of runway and went around!!

And here one from myself (ALL the above I got handfeed by an excellent instructor!):

Screw the centerline of the airplane!!
How far from the centerline of your airplane do you sit? A foot or two or three(do you fly a widebody or what??).

Line up so you have the CENTERLINE OF THE RUNWAY BETWEEN YOUR FEET and/or knees!
So you do not have to be worried where the centerline "hits" the prop or cowling or whatever......you can look straight ahead, have the line coming straight at you and concentrate on greasing it on!! (I do not a lot of instruction, but when I get to it amazes me how many helicopterpilots with more than 1000 hrs do not know how to track straight when hover taxiing but to the dog-walk. Mostly I can straighten them out by having them concentrate to get a reference line between their feet AND knees......and to FORGET about having the heli-centerline on the runway centerline!)

Let me know how it works,

Have fun,
3top :cool: :)

[1.3VStall]

In gliding we teach students to use the "reference point" on the approach (used to be called aiming point). This is the point at which the aircraft would hit the ground if the pilot didn't round out for landing. Having no throttle, the student is taught to use the airbrakes to maintain the reference point at a constant position in the canopy.

Of course the danger is that the student becomes so fixated with the reference point that he flies into it (ground attack pilots will be familiar with the term "target fixation").

We therefore teach the students to consciously raise their eyes to look at the far end of the airfield just before the roundout point - say 20' above the ground. This gives them the right perspective to judge the round out and subsequent landing.

After a while this technique becomes natural and I have to say that I don't have any trouble tracking the centreline of a runway either in a glider or my taildragger (for airbrakes substitute throttle) whether in a crosswind or not.

I hope this helps.

[Kermit 180]

Hello Cat Driver! Nope, Ive never been an agricultural pilot, nor do I aspire to do any spraying at this young and tender age :p . I can claim to have done some strip work, and as you can see, I am still intact and flying. Admittedly you dont always look at the far end of an undulating strip, but as was said, we were discussing a typical runway with a student pilot at the controls. Practical flying training proves it works. Taking your agricultural example on board, and giving some thought to what you were trying to say, I concede that you do still look subconcsiously laterally (as well), for depth perception above the ground. But the whole point of getting the student looking down the end achieves two things. First it gives them a good aiming point; secondly it prevents them from looking at the surface directly in front of them and getting ground rush, which results in flaring too high resulting in a bounce, a go-round from the recognised bad landing, or at worst a very hard landing.

Cheers.

Kermie :)

[CaptAirProx]

Catdriver, I agree with Kermit. I have never done ag flying so can't comment on that. However, by looking to the far end of the runway, as you get very close to the tarmac the angle of the runway flattens quickly. This is the point to fly level, close the throttle and then whilst still looking ahead for attitude control, you feel the aircraft down using your peripheral vision allowing the runway edges to slowly under your control come up around your ears. This stops you ballooning or shoving it on hard. So yes do look down the runway and yes do look down below. BUT not directly. If you do most pilots will lose attitude control and end up shoving the nose in first. Ouch. This looking ahead was described to me as the sight line swivel. Can't explain it here, need a white board! It does not matter how long the runway is. In fact the longer the better because it forces them into staring into the distance helping their peripheral vision.

Of all my students that have ever attempted to look to one side or lack any peripheral vision due to incorrect glasses have serious trouble pulling off a safe landing. So from my humble back ground my theory works. And thats the theory given from an ex CFS bod. PS It works in aicraft large or small, unless the cockpit (747) is very high where you will not see the sight line swivel as obviously. Thats why they have rad alt calls to tell you when to flare. But you can still control the hold off looking ahead and using peripheral vision.

Back to the original question, a lot of students/pilots during a crosswind landing/takeoff, see the aircraft weathercock and start putting in the wrong aileron because natural instinct is to steer like a car. This makes the into wing lift causing the weathercock to get worse and they then find they need unnaturally large amounts of rudder to correct and just panic thinking they have put to much rudder in. Correct answer, aileron into wind and keep straight with rudder. Simple. It may also boil down to the fact that with no centreline markings, one has to either look into the distance on a far object and keep straight on it. Or, use the peripheral vision to keep the edges of the runway symetrical. Comes back to the original point of my response.

[Chuck Ellsworth]

Good morning Kermit and Captairpox and everyone else out there:

This will have to be brief as I must leave for the airport soon to do some flying with the new owner of a Coot Amphibian.

When I get some spare time I will sit down and write a very full and understandable description of why we see such differing understanding of how to correctly fly airplanes.

Now please bear with me, I am not suggesting that I am the best and only teacher on earth however I have been fortunate enough to have not only learned from some of the best there is but somehow managed to live this long in the process.

We all are driven by our passion of flight and we all want to share our knowledge with others. So for free I will write exactly how I present my course for advanced flying. The course is "high command control" and involves very precision flying that I will not go into here at this time. Please remember it will take some time as it is difficult to put on paper so as to be understandable without the visual presentation of actually being in the airplane.

Our problem here is we all are saying almost the same thing but there is some differences in the actual sight picture presentation. For instance when I referenced "lateral" I did not mean to look i.e. turn head or eyes laterally, what I was referring to was the lateral position of the wheels in relation to the center line.

Another quick note: The distance one looks foward, or the center of vision foward will be determined by speed as well as eye height above the runway.

As to the comment on wide body and the computer call out in the latter stages of the landing,,I have not flown Boeings but have been given the training in the Airbus A320 as reward for teaching one of the Airbus test pilots how to fly the PBY with great precesion, It took two years during which we flew the PBY in North America, Europe, Africa and South America as far South as Santiago Chile and as part of the package I got to learn some of the A320 flying. And it was fun not to mention different, and the retard command does work.

Now I must go to the airport so until I get some more time will someone tell me where they think I should look when doing an inverted ribbon pick up?

Don't rush into the answer think about first.

P.S.
Sorry for the sloppy writing I just do not have time to correst it right now.
.............................................
Above all else remember:
:) The hardest thing about flying is knowing when to say no. :)

[ 21 November 2001: Message edited by: Cat Driver ]

[CaptAirProx]

Cat Driver. Your brief account of how you teach such subjects is interesting. There are plenty of ways to skin a cat. And I always like to poke my nose over fellow instructor's shoulders to see what works for them. I often find I learn something new that I can then pass on to the un-initiated. You say we (collectively) have such differing views on whats to be done. However, you then say we are basically saying the same thing. I'm confused now!

Your use of camcorders and some quite brain teasings titles for your techniques is quite impressive. I am unfortunate to not have the use of a camcorder, so I can't employ that technique. This means I can only stick to go old fashioned words, phrases and techniques - Get the bod in the pilots seat and demonstrate once with words and pointers. Then sit back allow them to have a go and use my skills to establish there short comings and gently point them to the right picture. This may mean allowing them to fly 1-2ft above the runway just above touch down speed. They accomplish this by doing what I said in my earlier response.

As someone said earlier, I think we talking in reference to initial training. i.e. giving someone a grounding from which to build their own techniques for the future. This has to be safe, consistant and understandable at all levels of intelligence. I am of the impression you are referring to advanced flying skills, of which I have less experience of training. I would therefore imagine the odd ab-initio student baffled by your use of words? I appreciate explaining on this medium is unrealistic. And I would still be interested to hear your method in detail.

I do object though to hearing you play down someone's quite reasonable suggestion in the light of the original question. (Think it was Kermit or Genghis). Particularly as you did say "we" do seem to be talking on the same theme. Just have different ways of saying it. "we" say - "looking down the far end of the runway", you say - ? gosh I can't remember what it was now. It confused me!!!

Anyhow I must get off this network now. Not because Im going to fly a very interesting aircraft such as yourself. But because I'm on standby for my company!

As to your final question......go on tell us, cos I know you want to. Ain't got a clue what it is but then I'm just an average pilot from the "pilot pool".

Safe landings!

ps I do agree with your foot note. Saying no is always the life saver.

[Chuck Ellsworth]

Captairpox:

Sorry you can not afford a camcorder and also that you think that I use brain teasing titles to describe my flight training.

I am however, "not" confused in any way with regard to my disagreement with the " Look at the far end of the runway " method to judge landing height and center line tracking.

Any flight training whether it be ab-initio or advanced should be taught using the most correct and safest methods to accomplish any manouver including landing and center line tracking. I believe that instructors are admonished to teach it right the first time.

So lets examine another senario.

For the sake of where to look during a landing flare and hold off to wheel contact with the runway how about this approach.

Fly down the runway at 10 feet at cruise speed ( Lets assume the runway length to be 5000 feet ) One thousand feet before reaching the end of runway pitch up into a right climbing turn (Being careful to allow enough height gain to keep from dragging your right wing. ) We will for the sake of simplicity here use a bank angle of no more than 60 Degrees, when the aircraft is 45 degrees to the runway you just pitched up from you roll the aircraft wings level and count four seconds while gently lowering the nose to level flight to prevent gaining excessive height above the runway. At this point you briskly roll the airplane into a left turn with bank angle not exceeding 60 degrees, at 90 degrees to the runway and now in level flight you begin lowering the nose to start the decent for your landing, as the runway comes into sight you will be in a position to complete the landing during the latter part of recovering from the turn. Your angle of bank at the flare will now allow enough clearance from the runway to prevent dragging the wing. However the aircraft is still turning and the landing is completed on the left wheel while turning to meet the center line, at this point the aircraft will be lined up with the center line you will run out of aileron effectiveness ( authority ) and the right wheel will settle onto the runway with the aircraft straddling the center line. Now that you are properly lined up on the center line and have the aircraft under perfect control all that is left is to allow the nosewheel or tail wheel to settle onto the runway center line..

Note:: I have neglected to mention power settings for simplicity.

At no point in this very simple manouver did I look at the far end of the runway..

The reason being I could not have performed that manouver looking at the far end of the runway, or at any other point except where the aircraft was being flown to.

By the way landing in a precisely controlled turn to touch down is easier to judge than with the wings level.

And oh-by the way my last question in my previous post was not meant to be condensending nor flippant, I was looking for someone to suggest where I should be looking, cause it could be really unhealthy to be inverted at ten feet trying to cut a ribbon and be confused as to where you should be looking. ( Here is a hint, I can assure you it is not the far end of the runway.)

And remember... ;)

............................................

:D The hardest thing about flying is knowing when to say no. :D

[Chuck Ellsworth]

I have control:

Re. your question on Nov. 18. You stated your problem was on touch down, therefore I assume the loss of runway centre line is after touch down during the roll out? With a nose wheel airplane you would of course look down the runway for directional control, providing the nose is not in to high an attitude to block your view straight ahead.

It will make tracking the centre line a lot easier of course if the airplane touches down tracking straight at the moment of touch down, inertia will then assist you in keeping straight whereas if the airplane is not pointed straight it will tend to head in the direction the thing is pointed requiring the use of at least rudder to get it straightened out.

Somehow I got sidetracked on the where to look prior to the flare and during the hold off portion of the landing discussion.

For some reason there is the missconseption among some people that flying airplanes is a some kind of black magic, terribly difficult thing to do.

It's not really difficult unless you make it so. Some flying schools and instructors make it difficult because for them it is.

............................................
:) The most difficult thing about flying is knowing when to say no. :)

[go with the flow]

I'm only just beginning (just solo) so don't take it from me, but...
in relation to CaptAirProx's commment (1st post previous page) about the weathercocking effect on takeoff, shouldn't this be permitted, allowing a crab takeoff with the heading somewhat to windward of the runway centre line and the track along the line? It seems to me that using aeliron to keep the wing down and opposite rudder to keep the nose/heading in line with centre is in effect a sideslip. Given that this is a drag condition, not much good for your rate of climb. And the C150 that the skies have granted me needs all it can get. :)

...and cat driver your 10foot radical cutback sounds like fun but i might leave it for the skateboard for now!

edited because i'd only got to the previous page

[ 22 November 2001: Message edited by: go with the flow ]

[Chuck Ellsworth]

Go with the flow:

You are at the most exciting point of your career, the early days of flying are something you will forever treasure.

You are also correct as to not slipping to correct for x/wind after take off, you will also find your landing approaches will be easier to manage if you crab to maintain the centre line until just prior to wheel contact, then just boot the thing straight with rudder and lower the wing with ailoren at the same time.

Remember it is your money you are spending so if you have a good instructor don't change. Unfortunately for aviation flight instructing has always been the vehicle for new pilots to build time and thus by default there are a lot of poor ones.

The answer on how to solve this situation lies in Instructor pay, if you pay peanuts you will get monkeys,,,sometimes,,,

I am not denegrating all instructors it is the system that needs fine tuning and the only sure way is to pay for truly qualified high time instructors, this will allow the schools to cull out the ones that do not meet a high standard.

Look at it from the students side. Wouldn't you rather pay twice as much per hour for a top notch instructor and learn it right in half the time?

As to the 10 foot down the runway with a 45 degree pitch out and a 315 Degree turn to reverse heading it is far from radical. Ask any crop duster they do it all day long, it is easier than flying a big circuit any day.

I must admit though that at your local airport it would create pure chaos if everyone in the circuit landed that way.

.............................................

:D The hardest thing about flying is knowing when to say no. :D

[CaptAirProx]

Go with the flow:

You are quite correct. I was talking about the takeoff roll. As the a/c begins to tranisition to a flying state, i.e rotate, you do indeed take up the crab technique to maintain the centreline.

Cat Driver:

Thanks for the reply. I am now at a loss as to where you are looking in this flare from the profile you have used. I have assumed from the intro that this was to prove a point to me? I cannot find having re-read the profile, where that info is......Can you further inlighten me? Maybe I am thick but please be patient with me! I can't for one minute believe you flare whilst looking right/left at the appropriate wing tip throughout the manueuvre. I have practised many a landing like the one you describe, normally in a Citabria or similar, but not beginning from the original profile you suggest. Even when flying the aircraft in my "day job" at night onto a max-crosswind landing, I am using the cockpit windows and or head/body position relative to the horizon ahead to get the roll cue, whilst still looking ahead for pitch attitude cues for the holdoff.
And yes, I indeed, depending on the type, always "boot" of the drift and apply wing down during the flare to touch down. Although I tend not to boot the rudder as granny in row 13 would be rather alarmed! More a case of "aligning the nose with the centreline by use of rudder" Same thing I know! I always get my roll cue from looking ahead. Whats your secret?

As to the camcorder, well yes I suppose I can't afford one really, not for the amount of use it would get. I only instruct/examine one day a week now. Its a hobby for me, so could think of other ways of spending that pocket money from instructing!

Anyway, sorry to drag guys, but please Cat, can you give me some more info. Cheers.

[Chuck Ellsworth]

Captairprox:

I have no idea why you would think I would be looking at the wing to judge the approach, or flare, or hold off and touch down.

I do think that using a key board to try and paint a picture is our problem here.

Let me try again. In the approach I described I must look at the flare point that I am aiming for from the time it comes in sight, then while still looking at the point of flare I control my bank attitude to avoid dragging the wing during the flare and hold off. Once the airplane is in a position in relation to the runway that I can see it through the windshield I judge the bank attitude while looking out the cockpit windshield. i.e. straight ahead in relation to the longitudinal axis of the airplane.

Were you and I are not on the same line of thought is my reference to not looking to far ahead. To put it simply there are flight instructors who teach the student to look up at the far end of the runway just prior to the flare, and keep looking way into the distance holding the airplane in the level attitude and ""feeling "" for the runway.
This usually results in an arrival.

I believe in flying the airplane with a sight picture that allows me to "fly" the airplane to a "landing" not an eventual "arrival".

Also the reference to the inverted ribbon pick up was only to point out the very simple fact that you have to look at the target. The point of flare on the runway is a target.

Now please e-mail me if you do not understand what I am describing and I will be most happy to clairify this further.

Do you agree with my beliefe that better pay will attract better flight instructors?


P.S.

My reference to " boot " the rudder was not meant to use a control imput that would produce anything other than smooth aircraft response.

Now tell me Captain, are you being condescending in the way you answer me? If you are, might it be the glare of those gold bars blinding you? :) :)
............................................

:D The hardest thing about flying is knowing when to say no. :D

[ 22 November 2001: Message edited by: Cat Driver ]

[CaptAirProx]

Cat, I wish I had the amount of bars that could cause such a reflection, thats assuming the pay scale is attached to it! I have emailed you for further chat.

I brought up the 'boot' comment because if I said that to half my students, they would do just that. As always the student listens explicitely to the phrases you don't mean and ignore the ones that you do! Oh well, I was and still am a student of aviation, so can't really complain. Don't think we will ever learn!

[Toppers]

Sorry chaps, if the original posters concern is staying "two or three feet from the centreline on landing" then I think he 'aint got a lot to worry about.

End of thread surely?????????????

[Kermit 180]

Crikey! Aerobatic arrivals! Yep, Toppers, I reckon its all been said. :eek:

[Chuck Ellsworth]

Yeh, Kermit:

I had better quit while I am ahead. :) :)

.............................................

:D The hardest thing about flying is knowing when to say no. :D

[13579]

Landing is an art. You can make the approach into a science. Just use the rudder for pete's sake. Why does it usually take people 300hrs to realise that there are pedals on the floor. On the final approach, look at the numbers or wherever you like and use the rudders to position the aircraft on the centre line. Then use aileron to keep wings level. But once you've made a rudder input, hold it there, don't relax it, until you can see if you've applied too much or too little. What you need to realise is that you need to fly the A/C, don't sit back and let it fly you. The final approach and near the ground is the right place to appreciate the effects of the rudder. You may not be flying in balance anymore(not that anyone does anyway) but your positioning and alignment should be right

[CaptAirProx]

Kouger, as always, the simplist words are the best! Here, here!

[Chuck Ellsworth]

Well Kouger....

Let me mull your question over for a second or two.

Why does it usually take people 300 hours to realize that there are pedals on the floor??

It couldn't be because of poor flight instructors that don't know either could it?

Hey, but there is a bright side to this, it gives us the opportunity to make money re-teaching them.

.............................................

:D The hardest thing about flying is knowing when to say no. :D

[Genghis the Engineer]

I am reminded at this point of a QFI friend who didn't realise for 10 minutes whilst teaching a pre-solo student that he had a stuck PTT. On realising he turned the radio off, landed, and phoned to apologise to a charming lady air trafficker.

QFI - explains, and apologises
ATC - "No problem, I just put all my military traffic over to UHF and ignored the civvies. But, could I just ask you one question".
QFI - "Glad about that, what's the question?"
ATC - "What's this 'bloodyrudder' that you kept telling your student to use"

Absolutely true, I was drinking coffee in the crewroom as he made the call.

G