Tires & Innertubes.....POP goes the innertube

03-23-2009, 05:32 PM

Mike | Tires & Innertubes.....POP goes the innertube

What r u using for tires & innertubes on your plane...?

Saturday - Taxiing over to the ramp......POP goes the innertube, flat goes the tire.

Sunday - Oh Hum......

Monday Morning - Taxiing to the runway......a 737 behind me......POP goes the other innertube, flat goes the tire

Flying along......175 knots, 35% power (YES I said 35%...18/24) ......30 Knot Tailwind.

Monday Afternoon - Landing on the runway......POP goes the 1st innertube I replaced.....flat goes the tire.........Shoosh goes the runway light, Shoosh goes another runway light, Cursing is herd over the tower frequency, fire engines show up, ambluance shows up, lots of flashing lights.......No damage other than my pants. Nothing like POPing a tire while landing in a 15knot quartering headwind at 85MPH.

What the Hell......

The three innertubes were cut/torn in the same location on both mains. 15x600-6 Michelin Aviators W/?? innertube with about 10 hours on them. So, after a long conversation with the Michelin guy, we still don't know why this happened. What a crap day..!!

03-24-2009, 02:29 AM

jar59nh | Where was the damage on the tube??

HI Mike,

I'm just curious where the damage was on the tubes. This seems like something new to the fleet. I have never liked the sharp angle where the valve stem leaves the rim, it's much too sharp a corner and seems like a failure point.

Let us know where it failed.

Sorry about your troubles,

John R

03-26-2009, 07:29 AM

Mike

What r u using on the mains and nose....?

15 x 6 on the mains...?

5 x 6 on the nose......?

I have been working on a write-up. As the days go on, more info comes to light.

03-27-2009, 05:30 PM

Mike

The Michelin tires I am using are 15 x 6.0 -6. 120 mph, for the mains. I was told by Michelin that this tire does not have any metal except for the bead. After taking the tire apart I did not feel anything or for that matter anything sharp within the tire, just a lot of good old baby powder.

*Both main inner tubes (each side) blew out within 2 days.

*They both blew out in the same places.

*Both tires were new (maybe 10 hours on them).

*Cold days.

So what’s left..?

*Inner tube

At first I thought that the inner tube was mis-marked. The smaller one is marked 15 x 6.00 – 6. The bigger one is marked 15 x 6.0 + 6.00 – 6. When I ordered them last year from Dresser I asked for 15 x 6.0 x 6ply 160mph tires. I also asked to send inner tubes that fit the tires. They sent the oversized inner tubes. When I called them today the salesman said they have been selling this way for at least two years. Michelin mentioned that the inner tube is two inches bigger and if used will crease (remember brake pictures) and eventually blow out. I wonder how many airplanes have oversized inner tubes?

*Tire Pressure

The tire pressure is very important. If using the Michelin you need to L@@k at their tire chart. This tire is rated at 1950lbs. max loading. Two will give you 3,900 lbs. max loading (not factoring in the front tire). I was running about 3,400 lbs. Unloaded, the tire needs a min of 68psi. At max 73 psi. Something interesting, if you want to get the pressure right all the time with the load....measure from the center of the axel to the floor. This tire should be 6.1" (static loaded radius at rated load).

*Installation

So it can’t be hard to change a tire...... Na, just baby powder and patience. Michelin says to slightly inflate the inner tube, insert it into the tire and rotate it to get out the wrinkles. Similar to how I do it. Just make sure the inner tube rotates and is out of the way before closing the hub. You don't want to pinch the inner tube with the hub halves.

Surprisingly the inner tube did not leak at the stem.

So what happened...?

-Mis-marked inner tube

-Wrong pressure.?

-Cold temp.?

I spoke to someone at the airport that has also had blown inner tubes in the same place with no answers.

At this point, I still do not have all the answers……….

Top Left - McCreary 15 x 6.00.....MIS MARKED, Notice the fold marks

Bottom Left - Michelin 15 x 6.00 600 -6 ......NEW NEVER INSTALLED

Top Right - Aero Classic 15 x 6.00.......BLEW OUT

Bottom Right - Aero Classic 15 x 6.00.......BLEW OUT

Tire 15 x 600 -6