Ground Looping

[facthunter]

 Doesn't work so well in some Beechcraft which have the gear and flap knobs close together.. IF you don't hold the weight OFF the nosewheel  with back stick you will have some directional control difficulties also in some tri gear types . Lots of weight on the nosewheel makes it a wheelbarrow  which has the instability of a tailwheel plane regarding GofG effect but worse as it's a LOONGG way forward and only ONE wheel that's not very strong. It often ends up with the wing tip and the nosewheel  being the only contact points and over she goes on it's back.  Landing too fast is usually the cause of this phenomenon.  Nev

 

 

[Mike Gearon]

I researched this after I flew with my CFI from Nebraska to Madison South Dakota. He did tail wheel while I built cross country hours. He’d come in drenched in sweat and tell me he now understands how I feel and had a bit of empathy again for my ordeal/ fun learning experience. Madison flight school. Australians go there to learn at spraying to do inbetween firebombing gigs apparently. http://www.rigginflightservice.com/

 

Anyway, I researched tail wheels and found an article on this problem.  Can’t find it again now. My scratchings will have to do....

 

 

 

[Phil Perry]

Plus: it is less unstable with more download on the tailwheel giving the tyre extra friction so it definitely helps to put the stick in the correct position.

 

Of the two airplanes I usually fly: Super Decathlon with just the pilot in the front seat I can easily pick the tail up however  with the Pitts S-2C I cannot budge it myself, let alone with the pilot in the rear seat. Still, the Pitts gets twitchy halfway through the landing roll.

 

I recall that condition in a Pitts S2 intensely. . .AAAND at the same airfield Too !!. . .albeit in 1973. . . .

 

Oddly enough,. . I didn't have a problem with the Pitts S1. . .?. . .less swing moment for lower passenger weight perhaps ?. . .dunno . . .not an Aero- Maths man. . .

 

 

[Phil Perry]

 Doesn't work so well in some Beechcraft which have the gear and flap knobs close together.. IF you don't hold the weight OFF the nosewheel  with back stick you will have some directional control difficulties also in some tri gear types . Lots of weight on the nosewheel makes it a wheelbarrow  which has the instability of a tailwheel plane regarding GofG effect but worse as it's a LOONGG way forward and only ONE wheel that's not very strong. It often ends up with the wing tip and the nosewheel  being the only contact points and over she goes on it's back.  Landing too fast is usually the cause of this phenomenon.  Nev

 

One lazy 1970s Sunday, I flew into Bendigo in a C-210 +2 pax and noticed a Cessna Taildtragger ( 180 I think ) upside down on the grass off the side of the runway. . .there was no one on the bloody radio (as usual ) [ YES - Nowadays, you all use CTAF, but then, SOME airfields had Tower / Air Ground live comms,. . which was the case with Bendigo, Mildura and many other stations,. . .Others used 119.1 unicom. . .  I never found out how that had happened. . .and batted away my Friend's Wife's fears by telling her that it was an old wreck that the airport firemen used for practice emergencies. . . .Must be a story there,. . .but never heard it. . . .

 

Got some photos of us all at a Chinese Cafe of some sort, quite near to the airfield,. . .must get Son in law to scan them for publication on here. . .( oh the horror ) MIND YOU. . .the buttered King Prawns in teriyaki sauce and Fried Chicken wings in Singapore batter were absolutely incredible. . . .but that's another story

 

 

[djpacro]

I recall that condition in a Pitts S2 intensely. . .AAAND at the same airfield Too !!. . .albeit in 1973. . . .

 

Oddly enough,. . I didn't have a problem with the Pitts S1. . .?. . .less swing moment for lower passenger weight perhaps ?. . .dunno . . .not an Aero- Maths man. . .

 

What landing gear did the S-1 have? Lockable tailwheel keeps it straight whereas the standard Maule with vague steering allowed the tail to swing. Spring main landing gear instead of bungees tamed the bouncing.

 

 

[Yenn]

The real reason for a ground loop is insufficient rudder control. I can't understand the problem with Thrusters. I must have landed one at least 400 times and the only time I was uncomfortable landing was once when I decided to try what Tony, the self confessed Thruster expert said we should all do. That is wheel landing, not 3 point. I tried a wheeler and decided never again, it just didn't seem right.

 

 

[Phil Perry]

I believe that the S1 had the locking tailwheel, as it was much easier to land on a hard rwy, than the S2,. . .My instructor mentioned this, although you are stretching my memory now DJP. . . being an old fart and all. . .I'd been flying Keith Hatfield's Tigger, ( VH-TIG ) and then an Auster 6 ( VH-ARX ), for quite a lot of hours,. . .followed by a C-180, which had a lot more energy and was 'Interesting' in crosswinds . . .!  Having only One runway at Berwick ( 12 / 30 ) gravel,. . .crosswinds were a daily occurrence which had to be mastered or no flying was possible.  My old friend David Squirrell, Instructor and Cropduster flyer extraordinaire. . .Taught me all manner of horrible approach and landing exercises in crosswinds, for which I shall be eternally thankful. . .  he even sent me solo in his Pawnee,. . .promising to do unspeakable things to me if I bent it. . .R.I.P. David.

 

  The C-180 helped me when I transited to the Pitts. . . .but with the Pitts (as I am sure you know) ,. . .the experience as a tap dancer and Rock Drummer came in handy, especially landing at Moorabbin . . .with it's very Hard runways.  

 

In the early days following my return to the UK in 1983, I found a Pitts S2 owner who allowed me to play with one of his many toys for a couple of years. . ., for just the fuel used . .!.   I regret that he died in a Harley Davidson Motorcycle accident where some French Farmer reversed in front of him in central France, but that's another story.  As is the one about G-Loc'ing myself with a microlight pilot as a Pax. . .  another time for that tale . .

 

 

[Dick Gower]

• All taildraggers want to go down the runway backwards.  Fancy footwork is therefore required.
   
   
  
• Any drag that you can add at the back reduces a taildragger's natural directional instability. Having the stick back during the ground roll helps a lot.  The raised elevator provides aerodynamic drag and downwards lift which increases tail-wheel friction with the ground (particularly if it is a tail-skid instead).
   
   
  
• During the takeoff roll ground loops are less likely because the thrust force is adding stability, the rudder effectiveness is increasing with speed  and the influence of any crosswind component is diminishing.  One exception to this is when the tail is raised too early: the drag at the back is lost and the P effect from the propeller does the rest.  (So you can do it if you try hard enough!)
   
   
  
• Ground loops are most common late in the landing roll in light winds where the rudder effectiveness is diminished by the lack of headwind. An earlier transition to the brakes is therefore needed.
   
   
  
• A "wheel barrow" in a trike is actually the beginning of a ground loop but the nose wheel usually breaks off before any big change in direction.
   
  

 

[Dick Gower]

Having only One runway at Berwick ( 12 / 30 ) gravel,. . .crosswinds were a daily occurrence which had to be mastered or no flying was possible.  My old friend David Squirrell, Instructor and Cropduster flyer extraordinaire.

 

Lots of nostalgia there thanks Phil. Dave Squirrell still has a Facebook page and I get reminded of his birthday every year.  A very skilled instructor was Dave I watched him one day teaching crosswinds on 30 with about an 18 knot component.  He believed in chucking them in at the deep end! Dave started overhauling magnetos and generators in Bankstown in his later years.  TIGgy Tiger is in my logbook somewhere also.

I went to Keith Hatfield's closing down auction and bought two of his C150s for RVAC; they weren't too flash!

Thanks for the reminder of simpler days.

 

 

[Phil Perry]

Lots of nostalgia there thanks Phil. Dave Squirrell still has a Facebook page and I get reminded of his birthday every year.  A very skilled instructor was Dave I watched him one day teaching crosswinds on 30 with about an 18 knot component.  He believed in chucking them in at the deep end! Dave started overhauling magnetos and generators in Bankstown in his later years.  TIGgy Tiger is in my logbook somewhere also.

I went to Keith Hatfield's closing down auction and bought two of his C150s for RVAC; they weren't too flash!

Thanks for the reminder of simpler days.

 

Thank you for that Dick.   I borrowed Keith's 150s quite regularly up to 1976. . .making the time to do this on my regular trips to Melb from Brisbane.. .Initially for Elsa's Hamburgers ! ! !

 

Used KQM, RXV, DTC and a couple I can't recall. . . they were all well used, but I never had a maintenance issue with any of them.  I wonder what happened to TIGy and the Leopard Moth ?

 

I also used RSI the Victa 115, IWK, ( C-210 ) a Cherokee 6 and a couple of 172s + 2 PA28s. . I really Liked the Fuji FA200/180 (VH-FJL) for limited aeros. . .. wonderful days at what was the friendliest flying club I have ever been a member of.     Wifey found my 'Groupair' Wings recently !

 

Somewhere I have photographs taken at Casey Field. . .must clean out the loft and find them. . .

 

 

[CAVU Mark]

The pilot.

[Roundsounds]

Thank you for that Dick. I borrowed Keith's 150s quite regularly up to 1976. . .making the time to do this on my regular trips to Melb from Brisbane.. .Initially for Elsa's Hamburgers ! ! !

 

Used KQM, RXV, DTC and a couple I can't recall. . . they were all well used, but I never had a maintenance issue with any of them. I wonder what happened to TIGy and the Leopard Moth ?

 

I also used RSI the Victa 115, IWK, ( C-210 ) a Cherokee 6 and a couple of 172s + 2 PA28s. . I really Liked the Fuji FA200/180 (VH-FJL) for limited aeros. . .. wonderful days at what was the friendliest flying club I have ever been a member of. Wifey found my 'Groupair' Wings recently !

 

Somewhere I have photographs taken at Casey Field. . .must clean out the loft and find them. . .

 

I think VH-TIG lives at Goulburn NSW aerodrome and has done for many years. John Zyla is the owner as far as I know.

[Guest Machtuk]

OK, I'll start the ball rolling. What is the main cause of ground looping?

 

You don't need an aerobatic rating to ground loop???

[Student Pilot]

Riggin Flight Service - The Aviation Experts[/url]

Australians who fly firebombing aircraft are agricultural pilots to start with, they get experience flying AG before they go firebombing. As opposed to Canadian and American pilots who can get into fire bombing without any previous low level experience, we have fire pilots who come from North America to Australia who have never flown AG.

That link you included showed they train with Callair and Super Cub, firebombing pilots usually fly Air Tractor 802's. The fuel load in an 802 is more than the gross weight of either a Super Cub or Callair, then add 3 ton of retardant and just over 3 ton of aircraft. I'm a bit puzzled why a fire pilot would go to a school to fly those aircraft unless it was for nostalgic reasons.

[tillmanr]

Maybe to get tailwheel experience before the agpilot training?

[Student Pilot]

Could be but usually pilots of Lead aircraft, VLAT and LAT's don't go backwards to fly single engine aircraft. As I said, SEAT pilots wouldn't be flying the stuff that school is training on.

[tcsmith]

OK, I'll start the ball rolling. What is the main cause of ground looping?

[tcsmith]

Hello Folks,

 

I was a member of the gliding club at Benalla for a lot of years, and saw a lot of ground loops. Typically more experienced pilots got overconfident and relaxed back pressure on the stick during the landing run. You could pick them. The elevator was a visual warning for those watching. No Names!!!

Cheers

Terry

[Student Pilot]

In working tailwheel aircraft normally you wheel it on and depending on the aircraft and strip sometimes actually pole forward to keep weight off the tailwheel. As usual there's no one way of doing things, whatever works for you.

[Bruce Tuncks]

The particular aircraft matters a lot.

In choosing the main wheels location the designer has the following dilemma: If the wheels are too far back, the plane is easily put on its nose or overturned by braking forces. Old free-flight models often had the wheels well forward of the nose for this reason.

BUT this resistance to overturning comes at the price of groundlooping: The groundlooping moment is the product of the braking force and the distance between the c of g and the wheels.

If the wheels are real close to the c of g, the groundlooping tendancy is small.

Different designers have chosen different compromises.

[Flying Binghi]

In working tailwheel aircraft normally you wheel it on and depending on the aircraft and strip sometimes actually pole forward to keep weight off the tailwheel. As usual there's no one way of doing things, whatever works for you.

 

Yep.

 

And practice all techniques of operation that the aircraft offers - even bouncing. What yer going to do when you bounce it landing on that one-way no go-round strip and all you’ve been taught and since practiced is to power up and go round after all bounces...?

 

 

There’s even some tough ultralights let you practice ground looping - anyway, thats what I were told he were doing..?

 

 

 

 

 

.

[facthunter]

No matter how you land a tailwheel plane it's going to end up on it's tailwheel at some stage during the landing roll. That places the wheels at their most directionally unstable forward position in relation to the C of G and often not much airflow over the tailfeathers. A 3 point landing has the plane at minimum forward speed which helps if you lose it. It's a good short (or rough surface) field method.

You can also lose it taking off, IF you wrap on the power and raise the tail at the same time. IF you are smarter you will roll forward a definite distance before giving it the gun gradually and you lift the tail to avoid unsticking too slow which will happen if you leave it in the 3 point attitude for long enough and thereby allow lift off prematurely. You can also see where you are going better in some planes. ( C-180 types) You don't have to groundloop if you are cautious and good with your feet and READY to correct swings early rather than wait till full rudder won't do it. Crosswinds reduce rudder effectiveness ONE way. Gusty conditions make a wheeler mandatory and you must pin it on with forward stick (prop clearance limiting). IF it bounces first you will have a bad day as will be the case if you brake hard as you slow right up.. That's when you do like the wheels well forward. There IS a difference.... with Tailwheel. Not when you are flying. It's only when you are at the bottom of the sky and still moving.. Nev

[Mike Gearon]

I’m definitely not an aeronautical engineer. You can tell by the sketch above. Engineers call it “design by crayon”

 

However, this is how I design. I am a reasonably successful designer. Exaggerate the problems and look at them. Not saying you’d want to be flying plane A Best. Can’t imagine you could get it into a flying attitude until about 100 knots. Maybe it’d stay stalled the whole time. You’d take off by flying an over the hill runway. Plane B has a prop that is digging into the ground. It’s not going anywhere. Now, keeping in mind I’ve yet to pilot a tail wheel I think I’d land plane A best with bugger all chance of ground looping.

[facthunter]

Mike it's not so much the track that matters, it's the turning couple between the side load on the mains and the C of G when the plane deviates from a straight line and does a turn. Centripetal? Force. Nev

[Mike Gearon]

Mike it's not so much the track that matters, it's the turning couple between the side load on the mains and the C of G when the plane deviates from a straight line and does a turn. Centripetal? Force. Nev

Well, I’m starting to understand C of G and elevator induced load on that tail wheel plays a part. Looking at the whole dance going on as the aircraft puts weight on that rear wheel then starts to influence and potentially command the tail ends track. We have the fact that removing the tail wheel from the ground will remove its influence.

 

Returned to rudder directed rear swing.

 

Put the tail wheel back on the ground very lightly and it isn’t going to do much. Add back elevator and it’s more able to influence the aircrafts track. In a straight line and continuing straight all is well. Now, we add a rudder or one side brake induced influence on the tail wheel. The heavier the elevator pressure the less likely the rear wheel can move off track.

 

So, because I want to ground loop I’ll need to remove elevator pressure. As the body of the aircraft is swinging around I’ll have a small amount of time during which the elevator will remain useful to regain tail wheel purchase on the runway if I suddenly lose interest in ground looping as a new experience.

 

However, it won’t be long before the plane is so side on to the airflow that the elevator is useless.

 

At some point along the way the front wheel track has the inside wheel of the beginning loop also gaining much more command over the planes former interest in proceeding straight ahead. It’s at this point my example of a wide front wheel track comes into play and the aircraft could possibly be brought back to its former course.

 

In the process of writing this I also see my former expectation the wider wheel track is more stable remains true. It’s however far more important to have the tail wheel firmly in touch with the ground. Particularly as the aircraft slows and it would seem logical that it is when the planes lower inertia and less airflow command combine the narrower ground track could swing the back end around no matter how much elevator is applied as it’s becoming useless.

 

I don’t even want to think about brakes. Maybe my summer USA plan to learn tail wheel isn’t a good one or it’s a really exciting challenging one?