This would be as good a forum/time as any to report my own ground loop accident. Since the FAA and NTSB investigations have completed and my own disciplinary action has been decided, there is no reason but ego and embarrassment to stay quiet longer.

I was working on a tailwheel endorsement with a student (a Commercial ASEL holder and former CFI) and we were at about 5 hours of instruction given in the Cessna 150 tailwheel that my employer owns (this was a Lowe conversion not a Texas Taildragger). We were working on wheel landings and he had been a little shaky on rudder control after touchdown, but was getting better. On our first landing of the day (calm winds) he made a smooth touch and had good elevator inputs, but then started to drift left. I quietly instructed him to correct and he made a sudden and very strong overcorrection to the right. I gave full left rudder and opposite aileron (creating drag on the left wing to try to help straighten it out) and gave as much left brake as I could without loosing pitch control, but I just couldn't get it back. We gracefully continued turning right and when I realized we were going around I let off the brake and came back with the yoke in the hopes I could keep the prop off the ground. We slid to the right side of the runway and came to a rest facing 180 degrees from runway heading, with the left main wheel just off the runway. The left tire and wheel where damaged, the gear box tweaked, the tailwheel twisted and the left horizontal stabilizer bent. The left wingtip had touched very lightly. No prop strike.

The tower called and asked if we were ok and after I shut off the motor and the fuel, I replied that we were. An Alaska AIrlines 737 was waiting to take off and tower asked if we could move the plane and I offered to drag it by hand off the runway for departing traffic. They accepted this offer and we pulled the plane into the dirt. AA departed and the tower closed the runway. This sort of solved the whole issue of reporting it to the FAA and NTSB. I contacted the company and they sent a tug out and we hauled the plane to the hanger.

I won't go into all the details of dealing with the FAA, NTSB, insurance company and my employer, but while it was embarrassing and stressful for me, they were all fairly understanding and reasonable. It was classified as an "accident" (the gearbox damage was considered substantial) and goes on my record. On the other hand I was not required to take a 709 ride. The FAA enforcement officer just said in effect to be less willing to let students fly the airplane. He also suggested not teaching wheel landings, but since it is in the regs to teach wheel landings for the endorsement and I happen to think they are sometimes necessary (I really don't want to get into a 3 point vs Wheel discussion), I will teach them if I continue to do tailwheel instruction.

I kept my job instructing (my status is lower around the office), but since the insurance company totaled the aircraft, I don't have a tailwheel plane to fly anymore unless I buy one. I have been looking for one for a couple of years but haven't pulled the trigger on one. When I do I'm sure my insurance rates will be higher because of the ground loop.

I have, of course, gone over the whole thing in my mind and am trying to take something away from this besides just that tailwheel instructing is risky. I still don't think it has to be. In my style of letting the student make some mistakes and learn to recover from them, I let a student get ahead of me. I'm sure I will be more "controlling" than I have in the past.

I had never damaged an aircraft before and it isn't a good feeling....

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As I agree with allowing the student to fly the airplane, I too have had ground loops with students. Training is much faster and students much more confident when allowed to fly the airplane. The only mitigation to damage is to make sure the touchdown, whether three point or on the mains, is as slow as possible. When slow at touchdown, we need only roll a few feet to be slow enough that a ground loop will not damage the airplane.

The problem with the hold off rather than slowing down before we get there is that there is a long period of lack of control. Hold off means that the student keeps the airplane from touching down until it finally stalls. He does not control when it stalls. Using power/pitch to slow down before arriving over the numbers reduces this long period of lack of control significantly. And with power still on at touchdown, there is more rudder control. This is especially true with the wheel landing (in a mush down.) Landing is much easier for students who are allowed to reduce this long hold off period. And it is much more likely that no damage will result.

Yes, I have let them touch down too fast and have damaged the airplane. I really hate that and avoid it as much as possible. I still feel the student pilot is more important than the airplane.

Tail wheel 150's can be a handful to begin with. Don't worry about it, everybody walked away. Almost everyone who has flow long enough has bent a little metal. Mistakes are made, we take our kick in the nuts, and move on.

Like gb says you fly long enough you will join the stupid pilot trick club. Me and most of my friends have pictures and stories. The first few days after my stupid trick I were hard. But that goes away and it makes you a better pilot.

What doesn't kill you makes you better. There aren't to many problems that can't be solved with the application of $$$$$$$$$$$ Learn from others mistakes, you can live long enough to make them all yourself.

DON'T FLY WITH OUT INSURANCE! unless you can afford to replace a total.

G'Day

Don't beat yourself up over it. There's such a fine line between when to take the controls from a student and when not to, whether in tail dragger instruction or any other instruction. Students don't always react like you tell them to, whether it's too much, too little, or not at all, and yet if you become a stick-grabber, they aren't going to learn from their own mistakes.

Not sure I can recall all of the times I wished I'd taken control sooner, although none of them resulted in bent metal--and only one runway edge light suffered any damage!

But the circumstances will haunt you for awhile--that's normal.

Cary

Sorry to hear about your mishap. Pretty funny that the FAA guy suggested not teaching wheel landings, guess he's never read FAR 61.31(i). Darn shame about the airplane, I think I remember seeing it somewhere- white with black & silver trim? A fastback (pre-1964) if it had the Lowe conversion. Who bought the salvage from the insurance company?

Do you have a link to NTSB report?

Thank you for documenting the accident.

Yes Eric it was the black and silver fastback and was a decent plane, though I never liked how the tailwheel had basically no steering (too much angle between the plane of the rudder horn and the plane of the tailwheel horn)...the plane is still in our hanger and as far as I know nobody has bought it from the insurance company. If someone had the time and skill to do the repairs, it wouldn't be a big $ project as the bid was mostly labor...just a lot of it.

I don't have a link to the ntsb report but maybe I can get one.

My assumption is that the Cessna 150 gear was not designed for ground loop loads, since it is a "land-o-matic" style nose dragger and wouldn't likely ground loop in the stock configuration.
I, and a lot of other pilots I know, have "WHOOPSY-daisy-ed" cubs and champs with absolutely NO damage, or just a slight scuff on a wing tip.....

I think I would give the C150's gear-box at least half-if not more-of the credit....

Sorry about the blemish on your record, and bruise on your ego.

lc

lc I would love to be able to blame the gearbox on the 150, but the Lowe conversion basically recreates the gear box of the C-140 which was designed as a tailwheel aircraft. It is possible that the monocoupe aluminum construction of Cessna aircraft are less resistant to damage from ground loops than the tube frame construction of the early Pipers and of Maules, but I don't know. I know that we put loads on the aircraft that few if any tailwheel aircraft were designed for.

Bungee gears are designed to fail in an overload, saving the fuselage. That design feature was utilized at a time when most props were wooden and fabric work was cheap.

In the crop dusting world, we tended to train in ugly Cubs and Champs with wooden props. I have also flown behind engines that were dialed and the metal prop was home straightened and tracked.

contactflying wrote:The only mitigation to damage is to make sure the touchdown, whether three point or on the mains, is as slow as possible. When slow at touchdown, we need only roll a few feet to be slow enough that a ground loop will not damage the airplane.

Mr. contactflying, please enlighten me!
You come back to this point very often, but I'm not sure I get it. I presume this idea is related to your "hover landing"?
Even in light trainers, a pilot is still landing (stalling) at 40MPH or so, the plane just won't fly any slower using normal approach technique. I agree that you dont want to be landing at 50MPH under normal conditions, I think most would agree.
Is that the point you are getting at? Or is there something more?

Battson,

I am Jim Dulin. What I found more difficult to teach was the roundout, flair, and hold off approach. Myself and the student would become concerned with the approach of the other end of the runway at a time we should be concerned with dynamic and proactive rudder control.

Early in the Seventies I changed to the apparent rate of closure approach using pitch and power to slow the airplane prior to arriving over the numbers. This approach allows the student to use pitch and power control to put the airplane down on the numbers at or near stall speed every time. He uses the optical increase in rate of closure that takes place as we get closer to a target and as we get lower. By maintaining what appears to be a brisk walk rate of closure, he will decelerate the airplane before getting to the numbers (the target.) This takes away the long, uncontrolled wait necessary in the roundout, flair, and hold off approach.

On short final he can check just how well he is slowing the airplane by pulling back on the stick a bit. If this pulling back causes the glide angle to decrease (balloon,) he is too fast. He can fix that by decreasing power and adding a bit of pitch. If this pulling back causes the glide angle to increase (mush,) he is too slow. He can fix that by increasing power.

This crazy Army helicopter approach technique to land airplanes gave students such increased control that they soloed very quickly. They and I both understood that they would have to learn the more difficult roundout, flair, and holdoff approach technique for the 1.3 stabilized approach on the PTS. It would seem that having to learn two rather than just one approach technique would decelerate learning rate, but that has not proven to be the case. I guess it is like learning English. We used to punish Navajos and Mexican kids for using their native language thinking this would accelerate their learning of English. This was proven not to be the case.

I would not be such a fanatic about the apparent brisk walk rate of closure approach if I had not been so successful with it. Over many years, my zero time students soloed after around six or seven hours and completed PPL around forty five hours. I had the advantage of having lots of farm kids who were familiar with equipment. The airplane is a very simple machine, by the way. I also had many foreign students who did as well, however. Most were young, which was a big advantage.

contactflying wrote:Early in the Seventies I changed to the apparent rate of closure approach using pitch and power to slow the airplane prior to arriving over the numbers. This approach allows the student to use pitch and power control to put the airplane down on the numbers at or near stall speed every time. He uses the optical increase in rate of closure that takes place as we get closer to a target and as we get lower. By maintaining what appears to be a brisk walk rate of closure, he will decelerate the airplane before getting to the numbers (the target.) This takes away the long, uncontrolled wait necessary in the roundout, flair, and hold off approach.

Thanks Mr. Dulin,
The description you've written seems to be the same approach I was taught (trained 11 year ago), power and pitch to control rate of descent and airspeed respectively. Basically, holding the threshhold in the same place in the windscreen to guide you in just short of the numbers, then you round out over the threshhold and flare onto the first 20ft of airstrip (ideally). As you indicated, as a young lad I was able to go solo in the circuit in 5.2hrs TT practicing this technique.
Where does the term "brisk walk rate of closure" come from, and what is it's significance? Is that the plane's apparently movement relevent to the threshhold, or over the ground?

The Apparent Brisk Walk Rate of Closure Approach was taught at Ft. Walters in primary helicopter training. It is their term. Yes, the rate of closure is how fast we appear to be closing with the numbers or desired touchdown spot.

This approach could become dangerous if one had a chin bubble in the airplane. When the numbers disappear under the cowl, we are close enough to just use buoyancy, decreased relative wind noise, stick pressure and position, etc. to get it on from this very short final position. Of course we continue to keep the centerline between our legs with dynamic proactive rudder movement.

I have never had another pilot record airspeeds while I was making this approach (the manipulator of the controls must see outside.) I was afraid someone would use the airspeed indicator to attempt the same thing. This would be a huge mistake. By looking outside, our brain (the world's best computer) can compute all the variables. The airspeed indicator is a one trick pony. It is a trend instrument that is always behind the airplane. It solved the pitch attitude problem in IMC. For contact work, it is too slow. During IMC we force ourselves to not maneuver aggressively.

The plane has been sold...the new owner is removing the wings to truck it home. He says he doesn't know what he is going to do with it. Hope it gets repaired.

Where's it going?

Those that have and those that will...I used to give a lot of tailwheel dual instruction, in lots of different airplanes. I was doing pattern work in a Great Lakes with a guy who had a lot of Cessna time. The thing with the Great Lakes is that it has these squishy oleo gear - that has the effect of making a pilot think they are better than they really are, I mean I've seen beautiful (but inadvertent) wheel landings. The problem was that when the airplane slowed down a little, during the landing roll in a three point attitude, those cute little art deco tail feathers lost all their authority and while the pilot is thinking he's an ace, the airplane would occasionally head for the weeds...and guess what? There's not enough rudder to get it back. To make matters worse, it had heel brakes, which meant one had to take one's foot off the pedal to use the brake. We didn't damage anything, but went completely off of a 150ft wide runway, between runway lights into the dirt, dust flying all over the place. Did a 180 degree turn. I just sat there for a minute, knees shaking...The tower asked if we were 'experiencing any difficulty'. I resisted the urge to suggest he get a headset with some brains in it.

Cary wrote:Don't beat yourself up over it. There's such a fine line between when to take the controls from a student and when not to, whether in tail dragger instruction or any other instruction. Students don't always react like you tell them to, whether it's too much, too little, or not at all, and yet if you become a stick-grabber, they aren't going to learn from their own mistakes.

Not sure I can recall all of the times I wished I'd taken control sooner, although none of them resulted in bent metal--and only one runway edge light suffered any damage!

But the circumstances will haunt you for awhile--that's normal.

Cary

As a current student, I hate it when the instructor grabs the controls. I agree, how am I supposed to learn anything when they constantly have their hands/feet on the controls? I've stopped flying with one instructor that did that a few too many times without communication that they wanted the controls.

Before the days of intercoms, and during primary training, the instructor pilot, well, at least my instructor pilot, would hit the stick sideways sharply, then take the controls away, or point to the instrument that had drifted too far. The instructor was in the front seat of this tandem seat aircraft (J-3), and a nice guy overall, but you knew you had been reprimanded when the stick BANG happened. Even though I was in the back seat, I was expected at all times to know what was happening on the few instruments on the panel beyond the instructor.
Sometimes after the slap, we would head directly back to the airport, and at idle on the ground, where I could hear, and he had my full attention, he would explain firmly exactly how things "SHOULD BE DONE".....

Just grabbing the controls seems kinda gentle to me in retrospect....