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Comment by chrisco255 | Hacker News Reader

Did it roll after landing or before landing?

After touchdown, but it rolled sideways not end over end. This kept the fuselage intact and ripped off the wings (where all the fuel is) which is why everyone survived.

Just to understand: Did it roll upside down, with people’s head at the bottom, or sideways, with people’s back to the front of the direction?

It certainly ended up upside down.

What you describe in the second sentence - rotating around the vertical-axis - is typically termed a spin .

I think parent was saying the roll was along the planes' length rather than tail-over-nose, the latter usually result in the aircraft breaking up as the torque will be really high.

Rotation around the

- longitudinal axis: roll, controlled by ailerons.

- vertical axis: yaw, controlled by rudder.

- lateral axis (through the wings): pitch, controlled by elevators.

Thanks - those are correct terms for aircraft in flight, that don't apply to out-of-control vehicles on the ground. An airplane that loses traction and rotates about it's vertical axis is spinning, not yawing.

In case you (or others confused) haven't seen it year, this video clearly shows the sideways roll: https://www.reddit.com/r/CatastrophicFailure/comments/1isabt...

Maybe that would be a general great idea.. slide the people capsule away from the bomb in the final moments of a crash landing. But that would make it necessary to have the people capsule bolted on - with explosive destructible bolts and i think air-companies are not mentally ready yet for the crumble zone airplane.

Many airplanes (not sure about the CRJ) also have a center wing tank, which is directly under the fuselage, so would be kinda hard to separate cleanly. Also, explosive bolts might start a fire that wouldn't have started without the bolts...

And they purge the fuel, if its a controlled emergency landing.. but in a uncontrolled emergency.. to let go of the wings seems a good option for events to go.

No, they don't. The CRJ, and in fact most smaller airliners including the A320 and 737 do not have the ability to dump fuel.

In larger aircraft that do have the ability to dump fuel, the reason is to make the airplane lighter so it does not have do an overweight landing and the subsequent high-cost overweight landing inspection. It is not done to reduce the probability of a post-crash fire.

Dumping fuel is only one option. Burning it up is another, but obviously is going to be an option for ever fewer emergencies.

I saw a report that it was after touchdown.

I’m guessing wind, ice, or something else moved the plane off the centerline and into a crab, it hooked a wheel off the pavement, and cartwheeled. 100% conjecture at this point, just seems like a possible chain of events.

Toronto Pearson had wind gusts of 60km/h today.

Edit: listing to the ATC audio I think they said gusts in the 30s (man do they ever speak fast and mumble! Enunciate damn it! Unique New York), which is markedly slower than what the Apple Weather app reported for Pearson.

Remember that ATC will give wind speeds in knots, not km/h.

Doh! My mistake. Thanks for pointing that out

It was gusting at 33kts.

33kt/hr * 1.15mi/kt * 1.609km/mi ~= 61km/hr.

The weather app was right. Just different units.

Whoops of course! My mistake

Too bad the airport couldn't find the funds to put a dash cam in the tower. Grump grump grump.

They have the video, they’re just not in a rush to release it to grumps like you :)

We'll see. How come we never see tower video of other crashes?

Because the press doesn’t publicize NTSB reports months after the crash. It doesn’t have the same sensational draw to earn clicks. Look up the NTSB docket management system where they release all the reports (just be aware that they list photos as “Text/Image” but videos as “Other”).

We do?

https://people.com/new-video-dc-plane-crash-shows-final-seco... was an airport camera, IIRC.

That clip was shot by an amatuer with a hand-held camera, it isn't an airport camera.

No; this was the second to come out that night.

Look at the movement of the frame - it's hand held.

It's a recording of a screen playing the video, the hand-held aspect is the amateur getting the footage by pulling out their phone camera and recording a screen...

It looks like the video is taken from https://www.youtube.com/watch?v=VaIL2UOX4ss - it says it's "Kennedy Center Cam", it also wobbles, but that's probably wind. But yeah, it's not an airport camera.

Delta could have also stuck a few GoPros on this thing before doing a barrel roll.

Does nobody have a sense for the dramatic?

Where's Tex Johnson when you need him?

https://cdn.shopify.com/s/files/1/2604/4866/files/5aedc13c-3...

Here you go: https://www.reddit.com/r/aviation/comments/1is1qoy/video_of_...

the video was removed

Still there for me.

it was removed but someone put it here with some contrast editing https://streamable.com/jyga56

It was not removed, I just clicked the link right now and I can still see it.

We are both correct. Thank you

Here's another view. I was at least partially wrong - looks like the pilot just flew it into the ground. Hard enough hit to collapse the gear.

https://www.reddit.com/r/Damnthatsinteresting/comments/1isa8...

For anyone unaware, Walter worked for Boeing for years and probably knows more about planes than anyone on the forum.

It's likely not a morbid curiosity here, especially since noone died AFAIK, but genuine technical curiosity so he can see what happened, and perhaps educate us readers.

I don't suggest it is any sort of conspiracy, it seems more in line with the generally ancient technology in the air traffic control system, and COBOL for the government accounting systems.

Back in my 757 days Boeing ran individual wires for everything. I suggested using a bus to save weight and improve reliability. I just got blank looks in response. Modern cars use a bus now, and probably the airliners do, but I have no direct knowledge of it.

If the aviation industry is one thing, it is stubbornly conservative. Took like until about a year or two ago to finally get unleaded fuel approved for GA piston engines, and most of the piston engine designs in new production are like over half a century old because no one wants to go through the effort to certify any modern engine for aviation...

Yeah, I know, and I know about the leaded gas situation.

The thing about cameras, though, is you can buy an HD dash cam for $100 that records in a loop. Buy it, plug it in, and point it at the runway. It doesn't need anything beyond a wall socket.

If I was an ATC sitting in the tower, I'd probably just install one myself.

TBH there's enough of a "planespotting" hobbyist community who would love to have good quality camera footage of takeoffs/landings to probably finance great quality cameras at all major airfields covering all the runways/ramp areas/etc. just from ads from streaming. Also insurers (I actually work with a bunch of the guys at Lloyd's syndicates who do hull insurance for aircraft; I can ask them in a few weeks how much this data would be worth to them. For ramps, it would be "who backed into my aircraft while it was parked" issues. I worked on an airbase where someone drove a pickup truck into a super high end "one of two" high altitude long endurance drone, destroying 50% of the US Government surveillance capability in theater for about 4 months...)

I wonder if you could get an additional market of "plane X taking off from/landing at airport Y at time of day Z in weather W at time of year U" clips for TV/movies, or if they already have enough of that stock footage.

A very good clip of the crash has emerged from someone who just happened to be filming a landing from inside his car.

This kind of footage of an aviation accident should not be left to chance.

You were Arthur C. Clarke (geo sattelite case) of aircraft engineering ;-) Buses are wildly used since 90's. Mostly CAN, the same one used in cars and Avionics Full-Duplex Switched Ethernet (AFDX) - https://en.wikipedia.org/wiki/Avionics_Full-Duplex_Switched_...

I do have a degree in aeronautical engineering, but I'm not a pilot and don't know a whole lot about flight ops and procedures. Interestingly, I lost my fear of flying once I found out how airplanes were built. I used to know everything there was to know about the 757 stab trim system. It's been a few years, though.

I lost my fear of flying after watching videos of stress tests on passenger planes. Could not believe how strong the wings are.

The fact that people lived suggests after.

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