How often do Aircraft Tyres last?

On your car, you buy a set of tires that last for 40,000 miles or more. Airplanes spend much of their lives in the air (or parked). Their tires are only moving on the ground during the one-mile runway run and another mile to the terminal. Their VERY advanced, very expensive tires have a tread life on the scale of one hundred miles!

OK! When could enormous wear occur? During low speed taxiing? No, there is extremely little tire wear under those conditions. During a takeoff? A moderate amount of wear can occur then, due to the fairly high speed attained just before liftoff. But that cannot possibly account for a tire tread lifetime of just a hundred miles or so.

There are two situations during landing that can (and do) wear the tires extremely rapidly. Prior to large airplanes having ABS brake systems, it was possible for a pilot to apply the brakes so aggressively in slowing the plane down that he could "lock up" one or more of the wheels. If that wheel remained in that position, a LOT of wear could occur on one side of that tire, resulting in something called "flat-spotting". That is virtually unheard of today because of the automatic action of ABS brakes.

That leaves only one remaining situation that can result in rapid wear in the tires, at that instant of touchdown, when the very heavy non-spinning wheel and tire assemblies must suddenly be sped up to 130 mph (110 knots) by friction with the pavement of the runway. This fraction of a second, mentioned above, with its puff of smoke from wearing of tire tread and its skid marks that are additional parts of the tire that came off, is therefore the cause of virtually all of the wear on aircraft tires. In Physics terms, the contact with the runway must apply an enormous moment (torque) to give the tire/wheel an angular acceleration to get the rotation up to the necessary speed to avoid further skidding.

omgttfs wrote:

Funny thing is, I remember when I was about 10 (1980), I whatched a show that was discussing this extreme tyre wear upon landing. Someone had invented an fan/cupped attatched for the wheels that spun the wheels up with the wind speed which resulted in virtually no tyre smoke on touchdown.
What ever happened to that I wonder?

omgttfs wrote:

Hinch: It's a pity your girlfriend doesn't nag you about capitalising proper nouns, pronouns and the beginning of sentences..

Oh if only I had your courage. The only excuse hinch could possibly have is 'artistic licence' - seing that he's old enough to have a girlfriend

english is an interesting thing - treat it well.

hinch wrote:

why the hell would i captilise a pronoun anyway

LOL, you missed one in that sentence. "I" is a pronoun.

Now back in the corner!


...and yes, I understand the irony of starting a sentence about written English with "LOL".

LOL, you missed one in that sentence. "I" is a pronoun.

Now back in the corner!

Stfu - ROFL to your comment. This forum is not about Spelling, Its about Aircraft Tyres lol.



D0N'|' /\/\1\/\|) |33(4|_|53 4/\/5\/\/3A|2 |-|4S |333N 541|)

Figure that one out ^^ lol

dannyboy2005 wrote:

D0N'|' /\/\1\/\|) |33(4|_|53 4/\/5\/\/3A|2 |-|4S |333N 541|)

Figure that one out ^^ lol

Don't mind realise answear has been said
...thats the most i can make out of it :/ - and thats not even right.
Then again Im no expert at cryptography, and I was born just after the leetspeak generation


[EDIT] that should be "born BEFORE the" .... obviously

Last edited by ARD-DC on Thu Oct 26, 2006 9:33 pm, edited 1 time in total

omgttfs wrote:

hinch wrote:

why the hell would i captilise a pronoun anyway

LOL, you missed one in that sentence. "I" is a pronoun.

Now back in the corner!

'i' does not have to be capitalised so ner ner ner ner nerrr it's just common practice not a ruuuuuule

i'm more worried by the secret code eeeeep.

as it starts with 'i don't give..' i think i can guess the secret ASCII code of sorts maybe the CIA puts such things on their forms as a secret insult.

D0N'|' /\/\1\/\|) |33(4|_|53 4/\/5\/\/3A|2 |-|4S |333N 541|)

^Don't mind because answear has been said^

Took for ever to "right" that out. Oh dear CRJCapt,

hinch wrote:

'i' does not have to be capitalised so ner ner ner ner nerrr it's just common practice not a ruuuuuule
.

hinch wrote:

.. how so many languages don't use capitals because they're just not needed.

Only languages that don't use the Latin/Roman alphabet don't use majuscules, also known as capital letters. This makes your argument utterly irrelevant. After all we're dealing here with and are conversing in English.

Let me spell it out loud and clear: In English, capital letters are needed. In English, the nominative form of the singular first-person pronoun, I, is capitalized, along with all its contractions (I'll, I'm, etc).

I guess your statement that 'how so many languages don't use capitals because they're just not needed' is based on hearsay. I find it difficult to imagine that you would bother studying characters other than the roman ones you already know seing that to do the right thing by your fellow forumites doesn't seem to be worth your effort.

dannyboy2005 wrote:

back to my question

The tyre is very expensive and contains ALOT of soot, the black powdery stuff found up a chimney. This gives strength and durability, not so much grip. A Plane is only expected to do about 7 miles on the ground from departure to arrival.

I never knew that

dannyboy2005 wrote:

Did you watch same programe then?

No, I'm just old enough to have bought a lot of automobile tires. I must have read the brochure or something.

Ed

dannyboy2005 wrote:

LOL, you missed one in that sentence. "I" is a pronoun.

Now back in the corner!

Stfu - ROFL to your comment. This forum is not about Spelling, Its about Aircraft Tyres lol.