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Comment by sandworm101 | Hacker News Reader

The 717 is also one of the few large jets readily converted for gravel runways, giving it a long future in northern operations.

https://en.wikipedia.org/wiki/Gravelkit

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The upside is that the engines are up higher, making them less prone to ingest gravel.

The downside (for northern operations) is that they're perfectly positioned to ingest ice coming off the wings. I think there was at least one MD-80 crash caused by that.

https://en.wikipedia.org/wiki/Scandinavian_Airlines_Flight_7...

From perhaps false memory, I have the impression some Antonov jets were made with improved/gravel airstrips in mind?

Everything russian, from Antonov to the Bear bombers, are designed for rough strips. The classic russian design criteria are high-wings and oversized landing gear. The classic american design is tiny gear and low wings placing the engines within feet of the ground.

There are stability reasons associated with wanting the wing to angle upward, which is a characteristic of low-wing designs:

https://en.wikipedia.org/wiki/Dihedral_%28aeronautics%29

But the literal flip side to this is maneuverability. The russian approach (high wings sloped down) results in better turning and roll performance. If you look at american military planes, especially the cargo planes like the c5, they are generally look more russian with neutral or even negative dihedrals, high wings and high engines.

https://en.wikipedia.org/wiki/File:Galaxy_Antarctica.jpg

The "american design" probably makes maintenance easier?

It does, if I remember correctly (I used to obsessively read about airliners but haven't in a while). Rear-mounted engines require specialized equipment to gain access, so you see them less on larger, newer aircraft. Same for the wings. Somebody correct me if I'm wrong.

Specialized equipment = Ladders. Having engines close to the ground means you can open doors and check things without climbing 10, 20, 30 feet into the air.

The 737 is also specifically designed for gravel and short runways.

Short runways yes, but gravel kits were only offered on the 737-200 series with its low-bypass turbofans. The enlarged nacelles required to retrofit high-bypass turbofans to the already low 737 design ended that possibility.

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