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Comment by kijin | Hacker News Reader

The takeoff and landing stories seem to suggest that the excess thrust and responsive controls of the 767 make it safer than a more sluggish plane, since it can fly faster and higher out of a potentially dangerous situation.

I wonder if this is just the subjective feeling of a pilot, or if the 767 actually has a record of using its high power and maneuverability to avoid accidents that a 737, for example, would not have been able to avoid. There's a lot of information out there about actual crashes, but not much about narrowly avoided crashes.

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Probably a little bit safer, and much more comfortable for the pilots since the fuselage is so much wider. Airlines care about cost. On cost, the 737 is a huge winner, because it's the most produced airliner ever, by a wide margin. It also has a wide range of sizes, from 103 on a -600 to 188 on a MAX 10. There are lots of pilots that already have a 737 type certificate, there are lots of maintenance shops that can work on them, parts are very available anywhere in the world, and leasing companies like them because they are very common and thus a relatively liquid asset.

>There's a lot of information out there about actual crashes, but not much about narrowly avoided crashes.

Actually the FAA collects information about near-misses too, and records them in the same database that it uses for crashes, the rather unfortunately named Accidents and Incidents Data System (https://www.asias.faa.gov/apex/f?p=100:12::::::). Navigating the interface takes some doing, but every accident and near-miss is recorded there, sorted by carrier, source airport, destination airport, and aircraft make and model.

For example, here (https://www.asias.faa.gov/apex/f?p=100:18:::NO::AP_BRIEF_RPT...) is a incident in which a plane caused another plane to abort takeoff by using a taxiway without clearance.

Another incident (https://www.asias.faa.gov/apex/f?p=100:18:::NO::AP_BRIEF_RPT...) where the plane overran the end of the runway and ended up in the grass.

The FAA is really good about collecting data on aviation incidents. Making that data available to the public is another matter.

NASA's aviation close-call database, however, is entirely open to the public. And these reports make for some great reading!

https://asrs.arc.nasa.gov/search/database.html

Ability to apply excess thrust is a big advantage when hitting wind shear on landing. Or when you lose an engine.

I suspect a big advantage of hybrid electric aircraft would be faster throttle control because electrically driven fans would spin up fast.

I sometimes hear that it's safer to drive a car with a more powerful engine, other things being equal, because the extra power gives you the ability to accelerate out of a dangerous situation. I've always found that argument a little dubious, because very few people have the training to accelerate safely in such a situation. On the ground, it's usually safer to stop a.s.a.p.

When you're flying a fixed-wing aircraft, however, it's not an option to stop where you are. So I guess it can be handy to be able to fly away at a high speed and steep angle!

The story comes from towing, where the vehicles are often only stable in tension (if weight is poorly distributed or strange aerodynamic loads) and you can damp the oscillation by hitting the gas on the tow or the electric brakes on the trailer. It you try to stop the oscillation by hitting the brakes on the tow, you'll end up in a horrible accident.

The aerodynamic load of a trailer is enough at highway speeds that its like hitting the trailer brakes already if you panic and take your foot off the gas, so if that didn't cause a recovery you're best off flooring it to get the system in tension which usually eliminates sway, then carefully slow down.

People who haven't looked into the mechanical engineering of towing are often confused why 400 pounds of stuff in the pickup bed is no problem but 400 pounds of trailer requires strange elaborate sway bars and brake systems and strange dampeners on the hitch... its a oscillation damper not a total power dissipation issue.

In theory a perfect aerodynamic and weight balance tow and trailer would never fishtail at any speed; in practice of course they do.

>400 pounds of trailer requires strange elaborate sway bars and brake systems and strange dampeners on the hitch.

You don't need any sway control whatsoever so long as the weight distribution is sane for the speed you want to travel. Look at large boat trailers for examples. They never have sway control unless the owner adds it because they want to load the boat farther back (because their vehicle can't handle the tongue weight).

Vehicles not being able to handle the tongue weight of a properly loaded trailer is becoming less of an issue for light loads because asinine CAFE rules force OEMs to push the axles to the very edges of the vehicle increasing wheelbase and reducing rear overhang so your average car or small/midsize SUV today can handle tongue weight a lot better than 15yr ago.

>In theory a perfect aerodynamic and weight balance tow and trailer would never fishtail at any speed; in practice of course they do.

Only because people are idiots and procrastinate putting the heavy things in the uhaul until the end and then they want to drive 80mph with it. It's not a matter of theory vs reality. There are very few situations where you can't get good weight distribution if you have ten brain cells and ten seconds to plan how you're gonna load stuff.

Perhaps overall it's dubious, but I was once overtaking a large lorry on a 2-lane section of motorway, so I was between the central crash barrier and the lorry. As I drew level with the front of the trailer / the back of the tractor, the lorry started to drift into my lane.

Braking, I'd have had to avoid all of the trailer, but stamping on the accelerator got me out of his way before the driver realised and corrected to stay in lane.

I'm not saying that power is always the solution, but it's handy to have it in some circumstances.

I think it depends on the driver if they're able to handle the power during routine driving.

Here is a 7 second video of Tesla driver accelerating out of what would have been a bad rear-end accident: https://www.youtube.com/watch?v=GRR31NaXoVw

Sidenote: I too have a 2 channel (front and rear) Blackvue dash cam setup. I highly recommend it. It's already paid for itself when it got me back my deductible after someone hit me, whereas without the camera the blame would have been 50/50.

In (less civilized) countries with mountainous roads, I'd take extra power for overtaking since you often move in to the oncoming lane to do so. With a smaller engine you could be stuck behind a truck for 15 minutes.

Obviously depends on road conditions, but stronger engine means you need a smaller window to make it.

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