[stackghost]

Gravel will happily fuck up a prop just as much as a turbine; it's more about ground clearance. The engines on modern airliners are quite low to the ground, which is why they tend to ingest gravel kicked up by the nose gear.

[CGMthrowaway]

What's the ground clearance of a flying piece of gravel! (in a gust of wind for example)

[stackghost]

>What's the ground clearance of a flying piece of gravel! (in a gust of wind for example)

I'm not sure I understand the question you're asking. "Ground clearance" refers to the space between the thing and the ground. Airliners are low-wing monoplanes with the engines slung underneath the wings, and aft of the nose landing gear. The tires at the nose can kick up gravel which not only dings up the underside of the fuselage but can also get sucked into the jet intakes. There's only about 2 feet of clearance between the engine cowling and the ground.

Compare this to a C-130 Hercules which is a high-wing monoplane with turboprops, which is designed to handle some degree of unprepared surfaces. The prop tips are never less than about 5 feet from the ground.

Or, compare to a Piper Cub which has much less prop ground clearance but has the prop mounted forward of the nose landing gear so it's much less likely to encounter gravel.

"What is the ground clearance of a flying piece of gravel" is... not really a question that makes sense to me.

[spockz]

I expect that “How high does a pebble get clear of the ground?” is what they meant to say afaict.

[CGMthrowaway]

"gust of wind"

flying gravel not limited to nosewheel kicks