Two questions, for the taildraggers I think.

[wombat13]

1. What does "groundlooped" mean?

2. What is a "wheeler landing"?

The Wombat

[Mark 1]

1. Loss of directional control on the ground (usually on landing) variously caused by landing with drift, overcorrecting small swings, not paying attention. CofG behind the mainwheels means that tailwheel aircraft have less natural directional stability on the ground than trikes.

2. Landing on the main wheels only, with the tail wheel held above the ground. This allows more directional control on landing due to slightly higher speed and less rudder masking than the alternative (3-point) landing. The CG behind the main wheels means that there is a tendency for the tail to come down on landing thereby increasing the AoA and sending you airborne again. The technique is usually to keep a small amount of power on, touch down very gently and apply forward pressure to keep the tail up after landing.

[John Farley]

How nice it would be if all replies to queries on PPRuNe were of this standard.

[High Wing Drifter]

I think due credit to the clarity of the questions too.

[AerBabe]

A groundloop is a loss of directional control on the ground, caused by a large audience.

A wheely good landing is superb directional control just above the ground, caused by a lack of audience.

[7gcbc]

A groundloop is a loss of directional control on the ground, caused by a large audience.
A wheely good landing is superb directional control just above the ground, caused by a lack of audience.


ain't that the truth :p

[orionsbelt]

Another question For Mart 1 ( is that GJG By chance )
Used to be the owner a Pitts S1c Ex homebuilt, which I wrote off at Norwich with the most spectacular of groundloops. It was fitted with the Old (Auster ) type Non Titanium Bungee cord system U/C.
The EAA Tech Tips was full of Pitts departure incidents, which were put down to the Toe in / Toe out of the main wheels changing as the A/C moved forward and that the A/C was Close Coupled.
I have read many definitions of 'Close Coupled' and none make sense.
1 What does it mean?
2 Why does it effect a Pitts more so than other Aero's types of the same basic design.
Cheers
Orions***

[HappyJack260]

Close coupled = short-arsed.

The S1 Pitts is only 15'5" so it is inclined to be twitchy - a longer fuselage provides greater directional stability, through greater inertia.

The undercarriage track is also narrow, so the aircraft is less stable, particularly when the pilot's inability to handle reduced directional stability leads the aircraft away from the runway centreline and the yaw leads to a roll and hence to a groundloop.

The Pitts S2B & S-2C are both a fair bit longer (about 4') so more stable, but still need care on the roll out.

[Mark 1]

No, not GJG, MWA in fact (PM if you want to know more).

I think you've raised a couple of different points here:

When people talk about close coupled for the Pitts, it really means that the short fuselage means that the tailwheel is relatively close to the CG. It also has a relatively low inertia (Izz in engineering terms), so is relatively easy to accelerate round the vertical axis (and all other axes for that matter), and the relatively short distance between the wing and the tailplane/rudder makes it less directionally stable in an aerodynamic sense - great for aerobatics, less great for relaxed ground handling.

As for toe-in/out; a small amount of toe-in will cause the drag to be reduced slightly on the inside wheel if a swing starts, and the yaw moment that this creates is stabilising i.e. it wants to swing you back straight again. For toe-out the converse is true, and any deviation from straight ahead is exaggerated. The elasticity of spring-bar type undercarriages means that drag on the wheel wants to turn the wheels outwards towards a toe-out configuration and also a tendency to shimmy. So, although good for weight, cost and simplicity; less great for ground handling.

Just off too play with the Chippy now for some relatively stress-free fun.

Oh and I agree, directional stability is also inversely proportional to the number of people watching.

M1

[7gcbc]

agree with all been said, I'm flying a s2b at the moment and I find the approach and flare much easier if you carry a few extra knots over the threshold, and approach and just hold the "picture" as opposed to other tailwheels which require . stick-this-rudder-that and so forth.

Higher approach speed = Increased directional stability which means reduced short couple tendency to behave like a bag o' squirrels
The Pitts, is, without doubt, the most challenging, and most delightful aircraft I have flown, then unfortunately, I have to land her............. :uhoh:

[HappyJack260]

7gcbc - you flying TKV with Curtiss at Camden?

[FlyingForFun]

An excellent trick for understanding stability on the ground:

Imagine attaching a piece of string to the aircraft's CofG, and pulling it along by the piece of string. Depending on the undercarriage configuration (tail-wheel/nose-wheel, gap between main wheels, gap between main and tail wheel, etc), you can see that some aircraft will be easier to pull along by your piece of string than others. The more difficult ones (tail-wheels, with the two main wheels close together and the tailwheel close to the CofG) will tend to want to turn around and be pulled along backwards - they're the ones which will groundloop most easily.

FFF
--------------

(PS Not sure where I got this tip from, but it's not my own idea so I ought to give credit. I think it may have been from "The Compleat Taildragger", but someone please correct me if I'm wrong)

[7gcbc]

HappyJack,

Thats the one, I think there's only one other 2b east coast, and thats in Victoria somewhere.

cheers

[HappyJack260]

HappyJack,
Thats the one, I think there's only one other 2b east coast, and thats in Victoria somewhere.
cheers

I flew that S-2B a while ago at Towoomba, before they sold it. What's the hourly rate for it?
You should come try the S-2C at Airborne Aviation, sometime. It's a little easier on landing, and performs quite a bit better in the air, thanks to improved controls and the 3-blade prop.

[BBK]

I was always told that there are two types of taildragger pilot: those that have ground looped and those have yet to....:)

[Them thar hills]

FFF
Re groundlooping easily, the missing words.... "if you let them "
So if a Pitts is challenging, a monowheel Europa is ???!!:)

[Hairyplane]

Right on the money Aerbabe!

Coming over the hedge at Old Warden in one of my vintage machines ( especially one of them!) in a blustery crosswind certainly makes me aware of the thousands of pairs of eyes watching for the bounce. I dont usually disappoint...

I have disappointed thus far on the groundlooping front but maybe 2006 is the year....?!:ok:

Hairy

[AerBabe]

I haven't groundlooped since my very first landing in a tailwheel ... a Chippy actually. I didn't realise that all the glider pilots on the field had come out to watch just the first landing of several circuits. I only realised later, when they asked whether I was learning ballet. I came close in the Aeronca once - again, I had friends watching. :rolleyes:

At least neither of those get quite the same attention as one of your aeroplanes, Hairy! Promise I'll shut my eyes next time you fly into NW. ;)

[BBK]

Perhaps I should have qualified that with: ".... when teaching someone to fly a taildragger". There´s not one instructor at my old club who has escaped that experience!!

Happy landings:)

[FlyingForFun]

So if a Pitts is challenging, a monowheel Europa is ???!!I couldn't possibly comment: I've only ever flown a Pitts once, and I was more interested in the aeros than the landing..... :} :} :}

FFF
--------------

[ChrisVJ]

My experience, and generally that of my fellow Searey pilots is that Toe in works the opposite way. Our older model gear has a tube strut angled about 50 deg down, with slip in tube on the inside of the fitting that carries the spindle and brake plate. The outer tube arrives drilled but the inner tube must be put in place, lined up as well as possible and than drilled on assembly for a bolt which then holds it all in place. There are three complications, one is lining up the wheels and holding them in place, second is the change in weight after doing so (usually done before adding engine and wings etc.) and third is change of toe in as the plane rotates or because of flex due to braking.

We all reckon that toe in exacerbates risk of ground loop. Land straight, say, the plane swings to the right, the weight increases on the left wheel which points across the nose and drives the nose further to the right. Seareys with dead straight wheels seem to work best. Loading and braking on the outside wheel drags it back to a toe out position which pulls the nose out slightly. Good landings are rewarded with no squirrelling. I have slight toe in. If I land unevenly, even slightly, I can feel the first wheel down push the nose in the opposite direction, worsens rapidly if not corrected.

[Hairyplane]

I'm told its a dog. Nasty on the ground to the point of being dangerous.

A very senior guy involved in flying them reckons it should never have been certified and that anybody flying one 'needs to be'.

Sweet in the air apparently so I guess the trike is OK??

Hairy.

[shortstripper]

If I recall correctly, the FRED drawings specifically state "no toe in" for rigging undercarriage.

SS

[185skywagon]

I have 2500 hr in 185's and would say that the long arm of the fuselage is relatively easy to manage until it gets beyond a certain point, after which it will be irretrievable. Absolutely imperative to keep any swings in check straight-away. Eyes to feet, without thinking.

I have done only 1 hour in a Citabria and found it to be fairly benign in terms of directional instability.

Wheelers can be done at almost any speed in the 185. Quite possible to land them with 25 kt tailwind, because you can pin them on and use brakes to slow them down.

Tail low wheelers are a fairly good method for the 180/185 types, for reasons of visibility and slower speed.
I can't speak for any of the Pitts types.
There is a Pitts at Trangie, with a 360 hp radial and large prop, that would definitely be a 3 point only machine. Has anyone else seen it??

[Pitts2112]

I can't speak for any of the Pitts types.
There is a Pitts at Trangie, with a 360 hp radial and large prop, that would definitely be a 3 point only machine. Has anyone else seen it??

The Pitts is best landed in a three-point attitude as opposed to a definite flare, or even tailwheel first, like a Cub or Taylorcraft. It was described to me as getting the airplane into the three-point attitude about a foot off the runway, then letting it settle by itself in that configuration. Seems to work just fine and is the method most of the people I've talked to use. On the intitial rollout, it's pretty stable because it's still moving at quite a clip. When it starts to slow, say between 30 mph and walking pace, is when it bites and gets into the biggest swings. As you said with the 185, you've got to correct any swing before it even really starts, and it has to become instinctual.

Haven't seen the particular Pitts you're talking about, but it sounds like a Model 12 with the radial engine. Big beast, lots of grunt, lots of noise. I've only ever seen one fly one time and the display was lacklustre to say the least. I hope it can do more than we were shown on that day because he did nothing with it that can't be done in an S-1. It'd be nice to think all that engineering and brute force produced something useful!

Pitts2112

[HappyJack260]

Interestingly, though, whilst we land the Pitts in a 3-pointer, the manual for the S-2C advises that the tailwheel should touch down first. This helps straighten the aircraft if there is any drift on, allows the aircraft to slow and avoids having the mainwheels touch first - which would increase the risk of a bounce.

Landing the Pitts is fun and a challenge. A circuit takes around 2mins 15 secs assuming a 1200m runway and a 1000' circuit height. You have no forward visibility for about 60 degrees either side of the nose, and essentially you do it by Braille. I took a nearly qualified PPL up a few days ago and he said to me, after landing, "I don't know how you did that, because I didn't see the runway at all!". I had to point out that if you could actually see the runway, you were probably not over it and therefore in the wrong place.

Add to that a glideslope akin to that of manhole cover (I reckon it's about a 2000 fpm descent rate from turning base/finals, to touchdown), and a rather higher speed in the circuit than most other aircraft (slow it down and the nose gets so high, you can't see a thing), and you really need to stay on your toes, even before you get to the rudder dance on rollout.

It's hard to get complacent, or bored, in a plane like that!!!:D

[High Wing Drifter]

It is certainly impressive watching the Popham Pitts slipping on their 71% descent gradient (seems like it) on the crooked approach for 26 and simply taking out the slip to track the runway for an gentle and almost anticlimatic touchdown.

[HappyJack260]

I always thought that was one of the more interesting approaches for a GA pilot - not quite Kai Tak - but still interesting. Then there's the water tower interestingly close after take-off and climb out. Is there still the other strip off to the right? Used to belong to Charles Church, I believe...
But it's probably almost purpose built for a Pitts, flying an oval circuit.

[Mike Cross]

The trees on the approach to 03 are also fun now, we need someone to come in slightly low and strim them please. In the meantime, with no flaps, my sideslipping is improving all the time.

The "Spitfire Strip" is still there though I've never seen anything use it. It may be a bit of a memorial to CC, whose widow Suzy owns Popham.

[Pitts2112]

Funny thing about Popham, as much as I love the place, is that I hate the two most-frequently used runways. 26 with that dogleg right hand approach is a right b*****d for two reasons. One is that I'm rubbish at right sideslips and the other is that you've got so little room to straighten out after the dogleg and put it down. 03 is a killer because of the sink over the trees (and their height!) and because the runway seems to slope away at almost exactly the glideslope of a Pitts. I was landing on it the other week and I thought the wheels would never touch the ground! Having said all that, they do sharpen up your skills, that's for sure!

HappyJack, interesting point about the landing attitude for an S-2C. I've never had the pleasure. I have done some short field landings in the S-1D, however, and gotten the speed right back to about 75 mph over the hedge (normally cross at about 80-85 mph and slowing). The nose was well up, no chance of seeing anything anywhere. She settled quite nicely and the landing was one of my best, but not one I'd care to make a regular habit. That was just a little too slow and felt like I was dragging her in.

Pitts2112

[FlyingForFun]

Monowheel Europa

I'm told its a dog. Nasty on the ground to the point of being dangerous.

A very senior guy involved in flying them reckons it should never have been certified and that anybody flying one 'needs to be'.

Sweet in the air apparently so I guess the trike is OK??Yes it's a dog, and yes it's nasty on the ground. I wouldn't say it's dangerous - just extremely unforgiving. But when you do a greaser in it, it's a magic feeling. And if you manage to do three or four in a row, so you know it wasn't just a fluke, it's a day to remember.

Absolutely fantastic in the air. I gather that the trike, though, looses quite a bit of performance compared to the monowheel (although I've not flown one). I am surprised not to have seen many of the conventional tailwheel Europas - have only ever seen one, and it was taxying out just as I was arriving, so I never got to have a close look or speak to the pilot.

FFF
------------

[HappyJack260]

HappyJack, interesting point about the landing attitude for an S-2C. I've never had the pleasure. I have done some short field landings in the S-1D, however, and gotten the speed right back to about 75 mph over the hedge (normally cross at about 80-85 mph and slowing). The nose was well up, no chance of seeing anything anywhere. She settled quite nicely and the landing was one of my best, but not one I'd care to make a regular habit. That was just a little too slow and felt like I was dragging her in. Pitts2112

The one thing it's hard to have too much of on approach in the Pitts is height - I turned in from downwind to base/final from 2000' the other day and still put it down just after the threshold. The one thing you don't want too little of, OTOH, is speed. Poor visibility in a normal approach turns into instrument flying, without the instruments, if you let the nose get high. I fly a continuous turning final approach until 100' to 200' AGL when I straighten up, still keeping the nose down so I can see where I'm going. I don't get the nose back until I'm over the runway and it's starting to fill rapidly in my peripheral vision. Then, like you say, it's a case of waiting, and holding off. With perhaps a touch of power if needed just to cushion an over-rapid descent. Things happen so quickly in a Pitts though that it takes a bit of practice to be able to see what's going on. And that big Hartzell Claw 3-blade prop turns speed into sink, like you threw out an anchor, when you take the power off.
Fun, though....

[stiknruda]

HJ - you make it sound like that you need to be a Sky-God to fly the Pitts?:confused:

I've flown the 1C, 1D, 1E, 1S, 2A, 2B, 2C

I have slightly more than 500 hours in them and I guess something in the region of 1500 take offs and landings.

It is just an aeroplane (albeit a fantistically fun one to play with!)

The bottom line is that with the right instruction and mind-set anyone could fly one, Pitts 2112 proves just that:E :E :E :E

Give these guys a break:ok:


Stik

[HappyJack260]

HJ - you make it sound like that you need to be a Sky-God to fly the Pitts?:confused:
I've flown the 1C, 1D, 1E, 1S, 2A, 2B, 2C
I have slightly more than 500 hours in them and I guess something in the region of 1500 take offs and landings.
It is just an aeroplane (albeit a fantistically fun one to play with!)
The bottom line is that with the right instruction and mind-set anyone could fly one, Pitts 2112 proves just that:E :E :E :E
Give these guys a break:ok:
Stik

Sky-God? Far from it. I have a little over 300 hours, and I have to amit that I approached the Pitts with a certain amount of trepidation. But it's an easy and fun aeroplane to fly, especially given its responsiveness; it's just that the same responsiveness means you need to be focused and alert on landing/take-off. And I'm happy to admit that the S-2C is easier to land than the S-2A (I've not flown the single seaters).

It's also a great leveller - as Budd Davisson says, it doesn't matter how many hours you have, when you first get into it. An ex-RAF fast jet pilot with thousands of hours on Jaguars and Boeings has no real advantage over a lowish time PPL. As you say, you just need the right attitude and instruction, and plenty of practice. But one of the great things is that it's hard to get bored with it!

[Pitts2112]

The bottom line is that with the right instruction and mind-set anyone could fly one, Pitts 2112 proves just that:E :E :E :E
Stik

Let's just say I like to use all my skills on every landing!

As Stik says, the Pitts isnt' really any harder to land than any other airplane, it's just a little less forgiving and needs loads of attention.

Pitts2112

[stiknruda]

Wylie, I didn't say that it was not any harder - I said that with the right instruction and mind-set anyone could do it!!

I think that the transition from say a Cub to the Pitts is quite a large leap. For me, I found my first 6 hours with the famous Budd that HappyJ refers to as quite bloody difficult, but with perseverence it became no less difficult but certainly more manageable.

HappyJ - if you know Budd personally, PM and I'll tell you my Budd story that has had some folk in ICAS wetting themselves!

Stik

[Pitts2112]

Wylie, I didn't say that it was not any harder - I said that with the right instruction and mind-set anyone could do it!!
I think that the transition from say a Cub to the Pitts is quite a large leap. For me, I found my first 6 hours with the famous Budd that HappyJ refers to as quite bloody difficult, but with perseverence it became no less difficult but certainly more manageable.
Stik

Point well made. And of course, it always depends on who's asking as to how difficult the Pitts is to fly:
If it's a pilot asking who's thinking seriously about getting into one and taking up aerobatics, it's not that hard and most people can pick it up with the right instruction and attitude.
It it's a cute, single, young lady with a nice smile, the Pitts is a hell of a beast that only the most skilled and brave of skygods can wrestle into submission. ;););)

Pitts2112

[7gcbc]

It it's a cute, single, young lady with a nice smile, the Pitts is a hell of a beast that only the most skilled and brave of skygods can wrestle into submission. ;););)
Pitts2112

I'd describe her as a graceful, elegant, intoxicatingly beautiful aircraft that plays with you lovingly until you make an inappropriate move with your hand, then you get slapped :uhoh:

Like most beautiful things in life, you have to take time to get to know the Pitts, you can't just rush it and she demands respect, or you'll pay the price