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This question stated that landing on pavement is hard on tires compared to grass, however I don't necessarily agree with that. Even if it is true the impact on the gear and other components may outweigh the benefits to the tires. This leads to the question of what is overall lower cost for takeoff and/or landing from a maintenance perspective, grass or pavement? If that cannot be determined what are the costs and benefits of each?

This question needs limits in order to avoid being too broad, so please assume these conditions:

  1. A tricycle gear airplane that can use either surface like a PA-28, Cessna 152/172, not something like a Mooney which is less grass friendly
  2. The grass surface is in reasonable shape
  3. Accident/incident costs are out of scope for the question
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    $\begingroup$ Slightly larger, wider and more rugged tires might be helpful for grass, you may wish to speak with "bush" pilots for possible modifications, which could also include STOL kits to further lessen the potential impacts, $\endgroup$ – Robert DiGiovanni Nov 12 at 15:21
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Pretty simple. Even a nicely rolled grass runway is nowhere as smooth as asphalt.

Tires on grass seem to last forever, but it wears out everything else in the gear out faster. Oleos get worked more; they get dirtier, so it's much harder on the scrapers and seals (dust (silica particles) + hydraulic fluid on the chrome = wonderful lapping compound), etc and can be expected to start to leak sooner. Scissors linkage bushings and wheel bearings wear faster. Fairings and bits that flex with the gear will crack sooner. All that sort of thing. Impossible to quantify, although tires are cheaper than oleo overhauls.

I operate from a field with grass and pavement (actually macadam - gravel/tar) side by side and I almost always use the pavement, because on smooth grass I can feel the oleos getting worked hard and they just get a lot dirtier.

On the other hand - if it's an option, I always do my engine run up on grass, and I usually start the takeoff roll (an option where I am) on the grass about 50 ft short of the threshold. These are propeller protection measures. Even nice clean looking pavement will have lots of, at minimum, very small pretty much invisible stones, which are murder on your propeller when stationary or when rolling at low speed/high power.

Props make great vacuum cleaners when close to the ground and pavement is like vacuuming a tile floor while grass is like vacuuming carpet without the beater attachment doohickey.

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  • $\begingroup$ But won't grass contain an equal amount or more dirt and micro-rocks? I have a hard time understanding how dirt and grass is better than pavement for runups. $\endgroup$ – acpilot Nov 14 at 19:36
  • $\begingroup$ The grass blades diffuse and inhibit the flow entering the little tornado that forms at the bottom of the propeller disc, so that the flow can't pick up small stones. Once I started doing runups on grass, my propeller ding damage dropped probably 80%. If you are on pavement that is totally clean, fine, but usually there is gravel nearby, the very small bits of which get blown on to the pavement and are invisible. Sweep up an area near the edge of a ramp and you'll usually find lots of very small bits of limestone. $\endgroup$ – John K Nov 14 at 20:40

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