Tires are a real big deal. After changing the tire the assembly should be contained in a very substantial cage and personnel in a safe area prior to inflation. At the gas station we used to put the wheel assembly under the hydraulic car hoists. This was mandatory especially with split rim wheels.
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Absolutely. I’m a retired RNZAF aircraft engineer and this is not a small matter at all. The tyre should have been fully deflated before being removed from the axle, and when in the workshop and being reassembled inflated in a substantial safety cage. Those bolts around the rim will be like bullets if they fail and the wheel explodes. But they are regularly and routinely NDT’d to prevent that. I wonder though if this is some kind of tyre failure? Either a manufacturing flaw, or over inflation?
Any tire whether auto, truck, or small or more so large airplane tires are bombs when inflated, especially 2 or 3 piece truck tires or the split rims used on airplanes, at 200+ psi! Always, always deflate airplane tires before removing from axle, in case of broken bolts or a crack in rim half. Any defects may be not noticeable until removing fastener holding tire on axle and if tire still inflated with come apart with explosive force. I used to test airplane tires and it was mandatory to inflate a newly mounted tire in an inflation cage to prevent injuries in case one did come apart. A hard way to learn a lesson. RIP to those who lost their lives, hopefully the injured one recovers ok.
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Even low PSI Tractor tyres will kill the careless. Happened in my home town when the main tire was filled to 32 PSI instead of the 12-18 PSI it should have had…
Many years ago, when it was commonplace in the NE to change from summer to winter (bias ply) tires, I worked at a very busy full service station. The first snowflakes lined customers down the block. My friend (and boss’ son) was operating the tire machine. One suddenly exploded, threw him across a 12’ service bay and into an Exit sign (on a block wall) above a man door, where he dropped to the floor, wearing only his underwear! Miraculously, he had only minor injuries. We never did find a reason, suspected a faulty tire. There is incredible energy in compressed gas. My condolences to the families.
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Condolences and prayers for the families. Prayers for speedy healing for the injured.
The tragic event shows how dangerous an aircraft tire explosion can be, with force similar to a hand grenade. While less deadly than a grenade, a tire burst can still be very harmful, especially in a confined space. This highlights the critical importance of safety when working with high-pressure aircraft tires.
RIP to Mirko F. Marweg and Luis Aldarondo, the two Delta employees who lost their lives.
AC 43.13…9-16. PERSONAL SAFETY. When servicing aircraft tires, personnel should stand either in the front or rear of the wheel and avoid approaching from either side of the tire. See illustration below: TIRE DANGER Safe Approach Area Danger Danger Do not stand or Do not stand or approach here approach here (see figure 9.16)… Deflate tires prior to removing them from the aircraft or when built-up tire assemblies are being shipped. 9-17. DISASSEMBLE THE WHEEL in accordance with aircraft manufacturer’s instructions. Do not attempt to disassemble wheel until the tire has been completely deflated: otherwise serious injury or damage to equipment can result. Do not attempt to remove valve core until tire has been completely deflated. Valve cores will eject at high velocity if unscrewed before air pressure has been released. Never attempt to remove wheel bolts or break tire beads loose until tire has been completely deflated: otherwise, explosive separation of wheel components will result.
Most people have no concept of the incredible amount of energy stored in a pressure vessel, of which a pneumatic tire is one. Even our lowly GA airplane tires can cause serious injury if not handled properly. I am actually surprised that the FAA considers replacing a tire to be allowed “routine maintenance” for non-A&P rated airplane owners to perform. A commercial airline tire is doubly dangerous because of both the high pressure and a large volume of contained gas. Raf’s comparison to a hand grenade is appropriate because of the potential for shrapnel if a hub bolt fails or the wheel rim is defective. My condolences to the families of the three workers.
North Korean fighter pilots once talked about the value of hitting the wheel wells of American bombers with cannon fire when approaching from below, according to my grandfather.
It’s very easy to get distracted and begin loosening wheel bolts before deflating a GA tire. Even though it’s stamped on the wheel.
Bullseyed tire (flat spotted to threads) can also be dangerous, and danger is from direction of bullseye (opposite the guidance for wheel maint).
Carrier pressure (about 50% higher than land) tire exploded on maint crew when they unfortunately coincided max brake heat transfer to wheel assembly post landing with touching the bullseye…life changing injuries for one and both were thrown many feet.
There have been instances where high pressure Nitrogen has been used for tire inflation and of course that ended in an explosion. Most tire carts I have used have both high pressure and low pressure regulators on the tanks and have been marked accordingly.