Are Our Tires REALLY that sensitive?

frankdamp wrote:
One of the big mistakes people make is to look at the max pressure molded into the sidewall and then use that as their inflation guide. Way too high and putting you at a much higher risk of a blow-out.

My approach is to buy good quality tires (we got Toyos), weigh the rig so you can figure out the individual axle weights when you're loaded for travelling, then inflate cold tires to the pressure the manufacturers' chart tells you. TPMS will give you a heart attack if you monitor what the pressure is while going 70 on the freeway in Arizona in the summer. Check it only when the rig has been sitting overnight and don't sweat it too much.

It really takes a lot of abuse to blow a tire. I worked in Boeing's landing gear group for a while, and we investigated an in-flight tire burst on a 727. It blew when the airplane was at about 12,000 ft, climbing out of Baltimore (I think). It punched an 18" diameter hole in the wheel-well pressure bulkhead and only a couple of USPS mailbags jamming in the hole prevented a disaster.

It turned out the airplane had taxied two miles with a dragging brake, then accelerated for take-off at close to maximum weight, needing about 150 mph for lift-off. After the gear was retracted, the heat build-up caused the failure, which was actually an explosion of gases that had been released from the tire compounds. The failure of the tire bead suggested an explosion pressure of about 12,000 psi. That's why airlines use nitrogen.

The "abuse" possible with an RV pales into insignificance. IMO, as long as you're within 15% of the pressure your weight calls for, don't sweat it. Being slightly under-inflated, based on a weigh-bridge check, is a lot better than being at the pressure shown on the tire's sidewall.

BTW, even after 47 years in the US, I still have trouble not spelling it "TYRE"! Fortunately spell checker alerts me.