Backcountry Pilot • Cessna 170B tailwheel damage.

Cessna 170B tailwheel damage.

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Re: Cessna 170B tailwheel damage.

When the tail wheel is turned to either side, the spring is loaded not just with the weight of the airframe, but the spring is low being twisted. Roll over a rock while swinging the tail around, and you’re not only boincin*the tail, you’re also twisting it. That’s not pilot abuse, that’s normal wear and tear.

Skywagons experience the same forces, but there is no deflection evident because the tubular spring will not deflect the same under torsional forces. The torque is transferred though the saddle, through the tubular pin and bushings, into the tailcone.

The T3 tail wheel will do the same. The bounce will be nicely dampened, but the torsional forces in the turns still exist. The T3 won’t show any deflection in that direction, but the tail still has to take it.

Lots of engineering required to demonstrate to the FAA that the force reactions between the T3 tail wheel suspension and the fuselage are within the design limits of the fuselage. Good luck.

A quote I read today that may apply here: “I once heard a financial guy say that from an investor's point of view, the best thing that could have happened is if the Wright Brothers had been shot down.”
Pinecone offline
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Re: Cessna 170B tailwheel damage.

Round spring should deflect forces equally no matter the direction of force
https://bhtailwheels.com/shop/ols/produ ... und-spring
Utah-Jay offline
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Re: Cessna 170B tailwheel damage.

Pinecone wrote:Lots of engineering required to demonstrate to the FAA that the force reactions between the T3 tail wheel suspension and the fuselage are within the design limits of the fuselage. Good luck


Hard to tell if that is a genuine good luck or not. I and many others have T3’s on our 170’s with FA’s in hand. The 170 version of the T3 is one of the greatest things EVER made! Anyone who thinks different hasn’t flown with one.
akgreg offline
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Re: Cessna 170B tailwheel damage.

The T3 looks well put together, anyone know the weight difference over a conventional setup. Can anyone put up a photo of a T3 installation on their 170 for a visual reference.
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Re: Cessna 170B tailwheel damage.

Mapleflt wrote:The T3 looks well put together, anyone know the weight difference over a conventional setup. Can anyone put up a photo of a T3 installation on their 170 for a visual reference.


Weight difference its about 2 more pounds (I read it somewhere, but not 100% sure) in my case I will welcome those 2 extra pounds that far back to move the CG back a bit.
IMG_3101.JPEG
motoadve offline
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Re: Cessna 170B tailwheel damage.

I fully realize it a fine line with getting a new product certified and to market. A large part of the process is keeping the "changes" as minimal as possible. However give the intent and significance of this item I would have liked to seen the loads carried further up the tail cone structure. The T3 is a work of art, seems very functional and may well be a better "mousetrap" but the limit surface contact with the fuselage has me scratching my head a bit.

To clarify I'm not a structural engineer or DAR, its just optics and a full on WAG.
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Re: Cessna 170B tailwheel damage.

Pinecone wrote:When the tail wheel is turned to either side, the spring is loaded not just with the weight of the airframe, but the spring is low being twisted. Roll over a rock while swinging the tail around, and you’re not only boincin*the tail, you’re also twisting it. That’s not pilot abuse, that’s normal wear and tear.

Skywagons experience the same forces, but there is no deflection evident because the tubular spring will not deflect the same under torsional forces. The torque is transferred though the saddle, through the tubular pin and bushings, into the tailcone.

The T3 tail wheel will do the same. The bounce will be nicely dampened, but the torsional forces in the turns still exist. The T3 won’t show any deflection in that direction, but the tail still has to take it.

Lots of engineering required to demonstrate to the FAA that the force reactions between the T3 tail wheel suspension and the fuselage are within the design limits of the fuselage. Good luck.

A quote I read today that may apply here: “I once heard a financial guy say that from an investor's point of view, the best thing that could have happened is if the Wright Brothers had been shot down.”


180/185 has a round tail spring, the 170 is like a piper with leaf springs. Pilot abuse is whipping it around and not making a slow gentle turn.
Pilot technique can protect both ends of the aircraft. Take a guy that has only flown grass or pavement all his life and put him on loose gravel strips, Vegas wont give odds on the prop surviving very many hours unless said pilot uses different techniques. Same for the tail wheel.
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