Aircraft Tyres - 4ply versus 6ply?
 

Will need to change spam can tyres next annual. Seems that although the original mains were 6.00 x 6 4 ply, I can buy same size with 6 ply cheaper as more easily available. What does the team think? Will they last longer/be tougher/ make any difference to handling/be allowed etc. ? Private use, ELA1 aircraft (C172)..........

Use the tyre with the ply specified in the aircraft maintenance or parts manual.

4 ply should be more than ample on a C172. More plies will generate more heat and won't last any longer.

Best value is likely to be a good quality re-tread.

Not much avalable in terms of re-treds this side of the pond, running three aircraft on a flying training operation working from a hard runway I have found the very cheap tyres to be bad value for money, and the top of the range Goodyear flight custom to be very good, however the best value in £/ per landing are the mid range tyres.

Is 6ply in the papers for the C172 in question? I tried it once and it was some (expensive) paperworks, but in the end it was not real better compared to the 4ply. I changed back.

OK - I've been surfing.....
 

Looks like it makes sense to keep with original 4 ply. Any recommendations re type and/or supplier? Looks like I need to spend about £300 for 2 including new inner tubes?

Watt's tyres are a reputable UK supplier.
If you can get them, I would recommend the Desser re-treads from Aero Classic.
I use the monster retreads with extra tread depth and get great service from them; about twice the life of typical first life tyres.

The new aero classic tyres that had been fitted by the guy who sold me the aircraft did not get past the first 50 hour check making them 1.5 x the cost per landing of the other mid range tyres on the market. Plus the labour cost of changing the tyres three times as often.

If you only fly off grass and don't do much flying you might be better off with the cheap tyres but hard runways and any more than 50 hours a year and any circuit work and you will loose money.

50 hours on a set of tyres, are you kidding? I did not change any and the tyres are still well after over 600 hours. Btw: what are your typical lifetimes for tyres?

If you maintain the correct pressures and grease them on gently instead of landing like a brick they last a lot longer.

A and C's aircraft do a lot of training. Heavy landings come with the territory.

Look at the tyre valve. We've got one tyre with a long valve, which would clip the spat mount if we put the valve cap on. New 2015 I think.

I've done 30 hours on my plane since I bought it in May mainly off tarmac, it has Condor tyres and they don't show any signs of wear yet? I had a leaky fuel drain valve which caused the starboard main to get an egg like bump. I assumed it was a no go item and went and bought a 4 ply 6*6 Airtrac from Adams Aviation in Croydon. £60 something pounds it was and a tube was £25 ish. But my CAMO said leave it a week and it will probably go, and it did! So I now have a spare Airtrac 6*6 4ply floating around in the back of the plane!

Chickenhouse
 

The Cessna 152's get about 200-250 hours life out of a tyre, this is training on a hard runway on quite a large airfield with a low cuicuit hight so ten landings an hour is posable. It also has to be remembered that if a tyre won't make it to the next check it is cheaper to change it before it is technically worn out because of the labour costs changing the tyre between checks.

On the other hand my Robin gets its tyres changed due to condition when they perish but that was regularly doing one landing per four hours flying.

I don't see 50 hours out of a low quality tyre being used for training on a hard runway as unusual or 600 hours out of a high quality tyre as being unreasonable if the aircraft is being used off grass most of the time and spending most of its time in the cruise, however experience has showed me that the mid range tyres give the best £/landing rate and don't cost too much when a student puts a big flat spot on one. If I was operating a high landing rate operation with experienced pilots ( such as glider towing ) I would probably go for the top of the range Goodyear flight custom as without the danger of tyre changes for flat spotting the Goodyear's extra life would save labour charges due to the longer tyre life.

I can only comment with the data that I have and the best part of fifteen years of training operation has drawn the conclusion that mid range tyres work for me, if your operation is different than the tyre option might well be different but I would remind you of the old proverb.......... Buy cheap Buy twice.

FWIW, my C 150 is grass runway 90%, paved runway 10%, 100 hours, 400 landings per year, and I am it's only pilot. I've replaced tires twice in 29 years of owning the plane, each time because of weather checking, rather than wear or damage.

I am sympathetic to A and C's high flight training toll on tires, and see my situation as the other extreme...

Just checked my logbooks. Current tyres are just 20 years old, and have flown over 1200 hours, mainly from grass. Now a little deteriorated by weather, but good service, so I'll be checking who manufacturer was tomorrow!

Id expect the TCDS for a C172 to state the plys on the tyres?

Ive just had a look at TCDS3A12 and it does not, my apologies.
Russ

Well there's a can of worms opened!

Yes, the TCDS is the top document which describes the approved configuration of an aircraft. Some TCDS do this better than others. The earlier Cessna TCDS had not been perfectly thought out. Details like tire ply count don't make it to the TCDS, unless there is something really unusual. Those details are nearly always found in the parts catalog.

However, when the parts catalog is not specified on the TCDS, it leaves a configuration gap. The earlier Cessna TCDS do not specify the parts catalog for the aircraft, and therefore the configuration is not certainly defined.

This configuration gap came to light with a friend's C 180, when he wanted to change wings (to get different fuel tanks). Though we could define which wings were supposed to be on the plane from the parts catalog, I noticed that nothing actually specified the parts catalog as the definition of the configuration of the aircraft. While discussion this gap with the government inspector, I asked him: If I taxied up in the aircraft, and you noticed the wrong wings were installed, what would you identify the non compliance as being? He did not have an answer....

But, before you decide to redefine your aircraft citing this regulator gap, note that there may be other regulations which require the use of the parts catalog.

Funny how various auto tyre manufacturers state that tyres need to be replaced after between 6 to 10 years, due to the effects of ageing making them unsafe to use.
What is so good about aircraft tyres that enables them to have no time limit on their replacement?

How Old - and Dangerous - Are Your Tires?

I don't think there is spectacular about aircraft tires, but their service is relatively benign. Decelerating in a straight line once from 60 mph (without getting the tires very hot) is not the same thing as driving a racing a car repetitively around a race track - which is what most car tires are rated to do. Experience has shown they don't often fail when they're older than recommended for car tires, and that's what matters.

My extreme (and not recommended by me!) example of old tires functioning on a light aircraft is remembering how a now passed on old guy (who BTW had a lifetime in aviation, founding pilot of a major airline, more than 100 antique aircraft owned in serial fashion) had mounted a 'new' set of tires on a Waco cabin biplane. I looked at them while helping him figure out a brake problem, and I noticed they were a very, very old brand. If memory serves they were B.F. Goodrich Silvertown, and he'd had them laying around the hangar for "quite a while" as he put it. A little research showed they were made around 50 years prior to being mounted! He flew the plane with them for a while, and then sold it.