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Discussion - Wheel On or 3 Point Landings?


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Guest TOSGcentral

WHEEL ON OR 3 POINT?

 

 

A more appropriate place for this may be the Training or General Discussion forums. I have put it here because I want to keep the focus specific to the Thruster models. There are significant operational and airworthiness consequences to the decision on what mode of landing that you make with a Thruster and I really do not want discussion diluted by the whole scenario of operating taildraggers generally.

 

 

There are a number of areas that I am interested in: Primarily I am after flight safety but a sound basis for that is based on any particular pilot’s state of mind. This can be expressed as confidence – and over-confidence may be more deadly than under confidence.

 

 

Confidence level may be expressed as what you do not know or cannot do, what you know and can do and what you think you know and can/cannot do. In the case of the Thrusters (but this applies to many other types) there can be a range of attitudes. The results of these attitudes may range from outright fear of the machine; severe inhibition to the conditions in which you operate the machine; operating the machine in conditions beyond your actual skill/knowledge level; or the worst one – operating the machine in a manner which you believe is the ‘done thing which has to be done’, perhaps because you know no other because you were never taught any other!

 

 

Let us first establish some basic ground rules (or basis for discussion if you like).

 

 

There are two methods of conducting an acceptable landing – the wheel-on (where the aircraft is alighted on its main wheels only, still with flying speed) and the 3 point (where the aircraft is brought to the stall very near the ground and settles on main wheels and tail wheel at the same time.

 

 

Generally the wheel-on is initially harder to execute than the 3 point in most tail draggers – but not in the Thruster! There are a number of reasons for this.

 

 

The principle challenge is that the angle of incidence (The angle between the chord line of the wing and the longitudinal axis of the aircraft) is too great. The aircraft therefore reaches the stalling angle before it reaches the three point attitude.

 

 

The aircraft may be 3 pointed successfully but a specific technique is required. This is to ‘snatch’ the stick back at exactly the correct time while there is energy enough to rotate the aircraft through the stall and into the desired attitude, but insufficient to balloon it. The aircraft will then sit down well.

 

 

This timing and technique is far harder to teach than the mechanics of the wheel-on and other factors come into play as well.

 

 

The Thruster has very positive reaction to engine effects through changes in engine energy. These all contribute to swinging the aircraft off it’s landing line. There is also a very positive secondary effect of aileron that induces very positive roll. The high lift wing then also contributes to taking the machine off line. If the stall is in process as well then you can get an alarming wing drop despite the aircraft having (normally) little wing drop tendency at the stall.

 

 

Any combination of these factors (while the student or pilot come to terms with the 3 pointer) cause alarming escalation of wear on the airframe – particularly on the all alloy Geminis.

 

 

In comparison – with the wheel-on landing the machine may be alighted very gently and under full three axis control. Simple techniques barricade you from the engine swing effects that the 3 pointer usually counters automatically.

 

 

The basic point I am getting around to is that the bulk of major crashery in the landing phase with Thrusters is a direct product of loss of directional control. Although the injury incidence is very low the damage bill can be huge! Just one bad landing could write-off your aircraft in economic terms. So it is well worth getting discussion going on landings and see if we can generally raise the act a bit more!

 

 

Now before you accept my forthcoming invitation to leap into print and give your own views I ask you to do a few things please. Would you honestly ask yourself if you really understand the implications of what ‘engine effects’ are in practical terms – not just that you are intellectually aware of them? I am talking primarily here about gyroscopic precession and asymmetric blade effect.

 

 

Also will you cast your mind back to when you were learning and not just dismiss this topic because you can now do successful 3 pointers so feel that everyone else can. That may be true but a lot of people find the challenge too hard and so we are only left with the success stories that tend to then dictate opinion.

 

 

To get the ball rolling I will come out with a firm statement that I both practice and teach.

 

 

The Thruster two seaters should be wheel landed as the landing of choice – for student ease of skill acquisition, safety of the operation and reduction in airframe fatigue.

 

 

However, pilots must have mastered the 3 point landing in them and remain current. This mode of landing is required for forced landings (especially off-airfield) as it results in the lowest touch down speed and the shortest ground roll.

 

 

Now, what are your views and let us chew the fat a bit.

 

 

Aye

 

 

Tony

 

 

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Tony.

 

I flew a Thruster for a bit over 200 hours. the very first landing with Dereck Robinson the owner on board I did as a 3 pointer, much ti his surprise. I then bought it and continued with 3 pointers. Not always pretty but I got it down. Somewhere along the line I was told I should be wheeling it on and when nobody was watching one day I did just that. I found that it had a tendency to go where it wanted rather than where I wanted so that was the first and last attempt.

 

My other tailwheel experiences have been in the Chipmunk, Fairchild Argus and Corby, where the recommended method is to 3 point them on. Maybe I will try the wheeler landing again and see how I go.

 

 

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In the Gemini, I always did wheelers, and kept the tail up for as long as it would fly. That seemed to introduce enough drag to slow things down. I always felt that I got down on the ground closer to the fence, whereas trying to do three pointers, it wanted to float into the paddock with less control over the touchdown distance. There was also less chance of hooking the tail wheel on the top wire of the fence if you flew it on.

 

With 200 metres to the next fence and no brakes, it was sometimes necessary to do a controlled ground loop if you got it wrong and that seemed easier to do with the tail off the ground. Less damage to the tail too.

 

David

 

 

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In the late 80's at Holbrook, I trained on Thrusters with the late, great, sqd. ldr. Mick Parer. He taught 3 pt as did all instructers after him. In those days it was a Gemini and the gear was not all that strong. He had a high opinion of the Thruster as a trainer and used to say, against the strident complaints of students that it was hard to land, a trainer must be challenging. We had very few accidents causing damage to our aircraft and found that 3 pt was kindest to the airframe. I am concerned that without the stability of having the tail planted, loss of directional control in the rollout would lead to groundlooping. However, in strong crosswind landings it is probably safer to fly it on with higher than normal a/s on its gear. I have never come close to groundlooping one, intentionally or otherwise. Kind regards, Don .

 

 

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Mea culpa...OMG!

 

Ok, I can hear you all laughing from here (which is probably a long way away from the rest of you!). You know the proverb that states that the last laugh is always the most satisfying? Today, I took my sweety for her 1st flight in the Thruster. We launched into 10kts straight down the strip and went up as though we had rocket boosters. Talk about impressive! Flew around for the standard 30 min sightseeing and then a GREAT landing (hardly felt a thing!). Then, all hell broke out as we lost directional control and veered inevitably to the side of the strip, taking out one of the painted tyre markers. The bolt acting as pinion between tailspring and wheel had snapped! All this just after declaring publicly (see my previous post), that I had never had problems landing a Thruster. Anyway the moral is if you have any doubts about the state of that bolt, check it and replace. PS: Damage was confined to u/carriage legs and pride! Any one know of a good spring fabrication business? I'm in need of 2 gear legs. Cheers, Don.

 

 

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You beat me to it. I was about to suggest that that "There are those who have ground looped and those who are going to ground loop".

 

As I recall, they used to have a bit of trouble with the tail spring assembly as there were a couple of lugs welded onto each side of the spring and because the whole deal was not re-heat treated after welding, one of the lugs would break off.

 

If you had wheeled it on, that might not have happened.

 

David

 

 

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David, the bolt that acts as pinion to allow the tailwheel to "steer" broke. I am fatalistic enough to beleive that letting go was inevitable given that there must have been a crack developing. I will now replace that bolt yearly. I also beleive that if we didn't hit the tyre marker at the runway edge very little damage would have occurred. I am with Yenn (see his post on this thread) and think that 3 pointers allow for better control in the landing. Just sod's law I guess! Don.

 

 

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  • 6 months later...
Guest ricardo

In my early hours on my TST, I would do as Tony says (and as I was trained to do), and "snatch" back quickly when I felt the stall coming on - and usually got a pretty good 3 pointer out of it.

 

Later I found that it was just as easy (and seemed to give a smoother landing) to take a more relaxed approach to it, and move the stick back quickly-ish and smoothly rather then snatch it, which results in the main wheels touching down slightly ahead of the tailwheel.

 

I never quite understood the advantage in wheeling it on, as you then have to go through the transition from tailwheel-up to tailwheel-down as you slow down, and since that happens at the same sort of speed as if you'd done a 3 pointer, you have the same control issues anyway, but also have the disadvantages of using more runway, and of exposing your tyres to more potential harm. The only advantage from a learning perspective I guess is that it avoids that need to feel/judge the "snatch". But if you have to learn that anyway, why not just 3 point all the time?

 

 

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  • 7 months later...
  • 1 month later...

OK I'll answer my own question

 

OK I'll answer my own question with how I have been taught and how I understand it - may not be entirely correct, hence my original question.

 

This is for a 'wheel on' landing - I've only every done a 3 point landing (in a tail dragger) in the Drifter and I have not discussed 3 pointers with my instructor.

 

Over the threshold at 55knots with about 4000 revs on the engine; round out and hold steady whilst bleeding off the power a little; keep holding off (you don't want to land remember) and the Thruster will settle when it's ready; on touch down feed in a slight forward stick movement to reduce angle of attack and make sure throttle is at idle; work the rudder ("you are lazy on the rudder pedals Pud") to maintain line whilst progressively feeding in forward stick to keep the tail up as long as possible; when the tail can no longer be held up and comes in contact with the ground, feed in full back stick to give the tailwheel positive contact and good directional control; remember the landing is not complete until you are at taxiing speed.

 

Waddayareckon fellow Thruster enthusiasts?

 

Pud

 

PS. I've just completed 8hrs in the Thruster and only now feel as though I'm starting to be in control and mastering the landings - will go solo soon.

 

 

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I think you've nailed it Pud.I wouldn't have described it ANY differently.Funny thing about the taxiing speed bit is...most times you take a new passenger up they want to start a conversation as soon as the wheels touch the ground,THE most important part of the flight!

 

 

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After Landing (response)

 

a nervous release. Great result, Like "We actually survived" the flight. Quite understandable really, when you think about it. Nev..

 

 

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Good point Nev.The way you have put it IS what happens.Unfortunately I can't talk back as this is the point of the landing where I am still holding my breath!

 

 

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