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Comment by tlb | Hacker News Reader

Landing speed for a loaded 737 can be up to 203 mph [0]. Among general aviation, a Gulfstream 450 landing speed can be up to 186 mph at full weight and high altitude. The drone itself can have some speed opposite to the airplane. 230 mph is only a little conservative.

[0] http://www.b737.org.uk/vspeeds.htm Note that numbers are in knots.

[1] http://www.code7700.com/g450_vref.htm

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But surely a 737 wing is completely different to the one tested here?

I'd be very interested to see a 737 wing being tested like this.

Completely different? No. Still mostly aluminum sheets riveted to spars with a big ol' gas tank in them. Biggest difference is the control cables would be mostly replaced with hydrolic lines.

Your referenced speeds for the 737 are for an overweight landing at the lowest allowable flap setting. 186 mph for the G450 would also occur at a weight above max landing weight. An incredibly low likelihood.

But we should consider the worst case scenario, not an average one. Thus 230 mph is conservative. They didn't even consider fast gliders, which alone can reach 460 mph.

14 CFR 91.117 restricts aircraft to 250 knots indicated under 10K feet.

Yet you can go on YouTube and see people fly them.

Do you have a reference for fast gliders? I’ve never heard of anything like that.

I don’t think the FAA plans everything for the worst possible scenario. The odds of a classic 737 landing at max take off weight and thus high speed are infinitesimally small. I don’t have a landing distance chart but at the max over weight landing it likely can’t even land on 99.99% of runways in the US in that configuration.

If the FAA planned and approved everything at worst case scenario then we wouldn’t fly anywhere.

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