tire wear - code 7700 · tire wear • correct inflation pressure is most important • check daily...
TRANSCRIPT
![Page 1: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/1.jpg)
TIRE WEARTIRE WEAR
John Salamankas
![Page 2: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/2.jpg)
Tire WearTire Wear
“Tires are one of the most underrated and least understood components on the aircraft.”
![Page 3: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/3.jpg)
Tire WearTire Wear
OUTLINE
• Pilot’s perspective– Oversee care– Contribute to wear
• Tire facts
• Wear
• Damage
• Proper Care
![Page 4: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/4.jpg)
Importance of Proper CareImportance of Proper Care
![Page 5: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/5.jpg)
Importance of Proper CareImportance of Proper Care
![Page 6: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/6.jpg)
Tire Performance EnvelopeTire Performance Envelope
Aircraft speed and load requirements are most severe
![Page 7: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/7.jpg)
Tire Design RequirementsTire Design Requirements
• Low ground bearing pressure, best “flotation”– Large amount of deflection
• Intermittent, short term operation– Can tolerate greater deflection
• Compared to automobile tires– 3 times the speed– 3 times the deflection (30% vs. 10%)– 6 times the pressure– 13 times the load
![Page 8: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/8.jpg)
Tire Design RequirementsTire Design Requirements
• TSO-C62e “Aircraft Tires– Dynamometer testing (same tire)
• 50 takeoff cycles at maximum load and speed• 10 takeoff cycles at 150% load• Taxi cycle matrix
– Inflation to 4 times rated maximum for 3 seconds– No degradation of tire material properties after:
• -40º F for 24 hours• +160º F for 24 hours• 300º F for 1 hour at wheel-tire bead seat
![Page 9: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/9.jpg)
Aircraft Tire ConstructionAircraft Tire Construction
![Page 10: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/10.jpg)
Tire DeflectionTire Deflection
• Tire contact area is flat
• Attempts to return to normal shape
• Overshoots because of high centrifugal force
• Rebounds with overshoot
• Sets up “traction wave” in tread surface
• Deflection sometimes extreme, varies– Load– Speed
![Page 11: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/11.jpg)
Tire DeflectionTire Deflection
![Page 12: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/12.jpg)
Tire WearTire Wear
250 mph 4200 rpm 1.9” deflection
![Page 13: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/13.jpg)
Tire WearTire Wear
TRACTION WAVE vs. UNDERINFLATION
Proper -10 psi -15 psi -20 psi
![Page 14: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/14.jpg)
Tire WearTire Wear
• Flexing causes excess heat to build– Weakens material– Leads to tread separation
• Flexing increases with speed and weight
![Page 15: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/15.jpg)
Braking and CorneringBraking and Cornering
• Wear increases with braking
• Anti-Skid most effective at 30% skid– Leaves rubber tire tracks– Can see antiskid releases
• Where do we see the most rubber?– Touchdown zone– High speed/sharp cornering
• Runway surface plays major role
![Page 16: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/16.jpg)
Tire WearTire Wear
New Brushed Concrete
![Page 17: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/17.jpg)
Tire WearTire Wear
Deteriorated Concrete
![Page 18: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/18.jpg)
Tire WearTire Wear
Grooved Concrete
![Page 19: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/19.jpg)
Tire WearTire Wear
![Page 20: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/20.jpg)
Tire WearTire Wear
![Page 21: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/21.jpg)
Tire WearTire Wear
• Correct inflation pressure is most important
• Check daily with an accurate gauge– Normal to lose 5% in 24 hrs
• Sidewalls are vented to prevent blisters/separation– Visual inflation check inadequate
• Paired wheels share load• Flat spot on bottom
• Inaccurate gauges are a major source of improper inflation pressure
• Check when cool
• Never bleed off excess pressure from hot tires
![Page 22: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/22.jpg)
Tire DamageTire Damage
Cuts
FOD
![Page 23: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/23.jpg)
Tire DamageTire Damage
Tread Chunking
Rough or Unimproved Runway
![Page 24: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/24.jpg)
Tire DamageTire Damage
Tread Separation
Excessive Loads, Flex Heating, Under Inflation
![Page 25: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/25.jpg)
Tire DamageTire Damage
Flat Spot
Locked Wheel/Anti Skid Fault
![Page 26: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/26.jpg)
Tire DamageTire Damage
Rubber Reversion
Hydroplaning
![Page 27: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/27.jpg)
Tire DamageTire Damage
Chevron Cutting
Grooved Runway
![Page 28: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/28.jpg)
Tire DamageTire Damage
Lower Sidewall Compression Break
Underinflation or Overloading
![Page 29: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/29.jpg)
Tire DamageTire Damage
• Primary causes of damage– Low inflation pressure– FOD
• Most FOD from hangar floor and ramp– Good housekeeping– FOD sweeps
• Secondary causes– Contaminants– Ozone
![Page 30: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/30.jpg)
Tire CareTire Care
• Tires no less important than engines
• Tire failure potentially catastrophic– FOD engine or aircraft system– Reduced RTO braking
• Two simple steps for safety– Proper inflation– Good housekeeping
![Page 31: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/31.jpg)
Tire WearTire Wear
![Page 32: TIRE WEAR - Code 7700 · Tire Wear • Correct inflation pressure is most important • Check daily with an accurate gauge – Normal to lose 5% in 24 hrs • Sidewalls are vented](https://reader033.vdocument.in/reader033/viewer/2022060217/5f064efd7e708231d41757d5/html5/thumbnails/32.jpg)
Questions