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YourNameHere
July 5th 11, 02:38 PM
Has anyone tried using the "Bell No-Mor Flats" foam rubber material in a
tail wheel tire as a safety backup. It looks like the 1.75" diameter
cut to the correct length might be a good safety backup if the tail
wheel tire gets punctured.
9U

T[_2_]
July 6th 11, 04:29 AM
On Jul 5, 6:38*am, YourNameHere > wrote:
> Has anyone tried using the "Bell No-Mor Flats" foam rubber material in a
> tail wheel tire as a safety backup. *It looks like the 1.75" diameter
> cut to the correct length might be a good safety backup if the tail
> wheel tire gets punctured.
> 9U

Are you suggesting placing this material inside the tire along with
the inner tube? Or in place of?
The 2" dia filler would not be enough and an possible extra friction
rubbing on an inner tube would be a problem.
Any tire pressure reduction from a leak could still cause the tire to
roll of the wheel from a side load during a turn.
I don't think you've added any safety factors without going to a solid
tailwheel that can support the aircraft weight and side loads on the
tire.

The aircraft weight on the tailwheel is a lot more than a bicycle
tire.

Also need to consider the impact of modifying a tire configuration on
a certificated aircraft without an STC.

Bob Gibbons[_2_]
July 6th 11, 04:50 AM
About 5 years ago I installed one of these into my tail dolly
pneumatic wheel (200 x 50). After seeing no problems I installed the
same into the tail wheel of my Ventus C (same size wheel).

No problems once installed, though the 20" x 2" model I used (20B7)
was about the same size as the fully inflated pneumatic tube, which
made installation of the wheel shims a challenge in the confined space
of the tail wheel well.

The actual rubber tube from No-Mor Flats varied between 1.65" and
1.75" in diameter.

Side note, the added weight was less than 0.5 lbs (1.735 lbs to 2.220
lbs), resulting in negligible CG shift in my configuration.

Bob

On Tue, 05 Jul 2011 08:38:52 -0500, YourNameHere
> wrote:

>Has anyone tried using the "Bell No-Mor Flats" foam rubber material in a
>tail wheel tire as a safety backup. It looks like the 1.75" diameter
>cut to the correct length might be a good safety backup if the tail
>wheel tire gets punctured.
>9U

BruceGreeff
July 6th 11, 10:46 AM
I used a section of an 18x2 inch BMX bicycle foam inner on my Std Cirrus
tailwheel for best part of 5 years. Never had any problems, it did
eventually start disintegrating - but it's a lot better than the
constant punctures from the thorns in the Free State. The main wheel has
a much thicker, harder outer and is not as susceptible to puncture.

Have the same installed in my Kestrel - which has a very heavy tail. No
problems so far - two years and counting. With my fat lump in the front
the little aft CG movement is welcome.

One suggestion, it is a good idea to make a scarf joint rather than a
butt join. On the Cirrus the sidewall scuffed a little and I flattened
the sides of the inner with a surform rasp.

Bruce

On 2011/07/06 5:50 AM, Bob Gibbons wrote:
> About 5 years ago I installed one of these into my tail dolly
> pneumatic wheel (200 x 50). After seeing no problems I installed the
> same into the tail wheel of my Ventus C (same size wheel).
>
> No problems once installed, though the 20" x 2" model I used (20B7)
> was about the same size as the fully inflated pneumatic tube, which
> made installation of the wheel shims a challenge in the confined space
> of the tail wheel well.
>
> The actual rubber tube from No-Mor Flats varied between 1.65" and
> 1.75" in diameter.
>
> Side note, the added weight was less than 0.5 lbs (1.735 lbs to 2.220
> lbs), resulting in negligible CG shift in my configuration.
>
> Bob
>
> On Tue, 05 Jul 2011 08:38:52 -0500, YourNameHere
> > wrote:
>
>> Has anyone tried using the "Bell No-Mor Flats" foam rubber material in a
>> tail wheel tire as a safety backup. It looks like the 1.75" diameter
>> cut to the correct length might be a good safety backup if the tail
>> wheel tire gets punctured.
>> 9U

--
Bruce Greeff
T59D #1771

aerodyne
July 6th 11, 02:45 PM
I try to avoid making even minor changes to my glider - reminds me to
much of my day job, where I would naturally consider effects of
flotation, shock absorbtion, material properties, and yes,
certification.

The tail tire of my open cirrus had many flats in the past, various
remedies were tried such as pieces of bike tire installed inside, etc.
using the cheap import tires definitly did not help. What solved the
problem was to use the BEST aircraft tire I could find (Tost 6 ply),
AND seal the openings between the valve stem to prevent debris from
getting inside. Some of the thorns were actually entering this way.

aerodyne

BruceGreeff
July 6th 11, 04:58 PM
Indeed, there is no substitute for a good quality main tyre. Even more
important is a good quality tube. If you can get one... Kestrel is Tost
6 ply + goodyear inner - but the tail wheel is not available in similar
durability.

On the other hand, the tightly shrouded modification to add a tail wheel
on my Cirrus was 30+ years old and made it very inconvenient to access
to inflate. Nothing to keep standard.

Talking of shock absorbtion etc - there is the horrible sound of your
glass tail end getting ground off on landing because the dinky little
tyre got punctured on take off. Personally, once was enough to motivate
me to look for a better solution.

If yours is US based and not experimental, maybe you have to live with
the results. In my and quite a few other folks experience the foam
filled tail wheel has been a well proven, good solution.


On 2011/07/06 03:45 PM, aerodyne wrote:
> I try to avoid making even minor changes to my glider - reminds me to
> much of my day job, where I would naturally consider effects of
> flotation, shock absorbtion, material properties, and yes,
> certification.
>
> The tail tire of my open cirrus had many flats in the past, various
> remedies were tried such as pieces of bike tire installed inside, etc.
> using the cheap import tires definitly did not help. What solved the
> problem was to use the BEST aircraft tire I could find (Tost 6 ply),
> AND seal the openings between the valve stem to prevent debris from
> getting inside. Some of the thorns were actually entering this way.
>
> aerodyne

--
Bruce Greeff
T59D #1771

RL
July 6th 11, 08:07 PM
Find a local tire place that deals with farm or construction equipment
and have them "foam" the tailwheel. You will never have to pay
attention to it again. The urethane fill has about the same flex
characteristics as a properly inflated tire so there are no issues
with shock absorbtion, etc. The foam adds about a pound to the
tailwheel, so do a new W&B and enjoy moving the CG back a notch. I
"foamed" my tailwheel about 5-years ago and our entire club fleet of
Grob 103's have been running the foamed T-wheels for at least 3-years
with no issues.

Bob

BobW
July 6th 11, 09:31 PM
On 7/6/2011 1:07 PM, RL wrote:
> Find a local tire place that deals with farm or construction equipment
> and have them "foam" the tailwheel. You will never have to pay
> attention to it again. The urethane fill has about the same flex
> characteristics as a properly inflated tire so there are no issues
> with shock absorbtion, etc. The foam adds about a pound to the
> tailwheel, so do a new W&B and enjoy moving the CG back a notch. I
> "foamed" my tailwheel about 5-years ago and our entire club fleet of
> Grob 103's have been running the foamed T-wheels for at least 3-years
> with no issues.
>
> Bob

"What Bob said,"...but mine was done in 1981 and hasn't needed attention
since. I still have a spare tire and tube, should the original tire ever wear
through, and FWIW, my ship has a significantly higher proportion of weight on
the tailwheel than do most single seaters. Ask the right 'heat related'
questions if your wheel is plastic/phenolic. Mine was (is); minor deformation;
fortunately not functionally problematic.

Bob W.

T[_2_]
July 7th 11, 01:54 AM
On Jul 6, 1:31*pm, BobW > wrote:
> On 7/6/2011 1:07 PM, RL wrote:
>
> > Find a local tire place that deals with farm or construction equipment
> > and have them "foam" the tailwheel. You will never have to pay
> > attention to it again. The urethane fill has about the same flex
> > characteristics as a properly inflated tire so there are no issues
> > with shock absorbtion, etc. *The foam adds about a pound to the
> > tailwheel, so do a new W&B and enjoy moving the CG back a notch. I
> > "foamed" my tailwheel about 5-years ago and our entire club fleet of
> > Grob 103's have been running the foamed T-wheels for at least 3-years
> > with no issues.
>
> > Bob
>
> "What Bob said,"...but mine was done in 1981 and hasn't needed attention
> since. I still have a spare tire and tube, should the original tire ever wear
> through, and FWIW, my ship has a significantly higher proportion of weight on
> the tailwheel than do most single seaters. Ask the right 'heat related'
> questions if your wheel is plastic/phenolic. Mine was (is); minor deformation;
> fortunately not functionally problematic.
>
> Bob W.

You are talking glider tailwheels, I was thinking tow plane
tailwheels!!
The aircraft weight load on the Pawnee is a lot more than on a glider.
And not too many side loads on a fixed glider wheel and not a
swiveling tow plane tail wheel.

T

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