Air India Express 737 Hits ILS, Damages Wall on Departure, Flies for 4 Hours

In 4hrs, they could have landed in Dubai itself easily

Being Indian, I agree with statement about AirIndia. I would never fly in AirIndia even if the ticket price is too low, laughably they usually cost way above than any other competitors.

How many articles posted here on HN tell you what a CPU is? Or a pointer? Or a container? And that's just to pick a few common terms. News about a certain topic will build on the assumption that the basic concepts related to it are already known to the reader.

The ground portion of an ILS consists of two antenna arrays, one at the end of the runway called the localizer, and one just off to the side called the glideslope. These arrays produce two fan-shaped signals that vary left-to-right and up-and-down in such a way that an aircraft can determine its location relative to the runway with remarkable precision. The localizer signal provides lateral guidance to the runway centerline, while the glideslope provides vertical guidance down to the touchdown zone, usually on a 3° glidepath. One or both of these arrays is what this airplane ran into.

The system is passive, in that the signals are simply broadcast from the ground continuously, aren’t unique to a particular aircraft, and there is no return or response from aircraft. The ground antennas simply “shout into the void” as it were, and aircraft receivers determine their location based purely on the shape of the signals at the aircraft’s location in space.

For illustration here is a localizer antenna (though note that the airplane in this picture is “backwards,” i.e. the localizer for a given runway is at the far end of the runway, though it is possible to “fly the backcourse” and land with one at the near end): https://image.slidesharecdn.com/instrumentlandingsystemils-1...

And here is a glideslope antenna: https://i.pinimg.com/originals/8f/56/b3/8f56b3b52fb9b81c84f7...

The cargo area of most airliners is not pressurized, so the gash is not an immediate problem.

In a case like this, the pilots would want to climb to several thousand feet and evaluate the situation before landing.

Looks like the pilot did a great job once it was realized the airplane was damaged of remaining calm and flying the airplane.

It's all speculation at this point.

Given the apparent structural damage, that was a risky decision.

I'm even more surprised that the plane could land on its own wheels despite the huge gash in the fuselage. Do landing gears retract so quickly, or was the wall simply not wide enough?

This does not seem like normal behavior from an airline pilot at all. I can see about 10% of private pilots doing something like this. It would probably be someone who has been flying a long time and gotten way too comfortable. Things always work out, so why not this time? The difference with an airline is its incredibly public flying. Even if the pilots disregard everyone’s safety (including their own) they know that they’ll be caught. You do something dumb and it’s going to be on the news, even if it all works out. How many of us can say that about or jobs?

The fact that the crew thought that this was a risk worth taking reflects really poorly on the safety culture of that airline. They thought that flying an airplane that was compromised some unknown amount was worth keeping the schedule going (or maybe people just wouldn’t find out?). That idea got informed somehow.

Also, more automated, single-pilot/ground operated or pilotless aircraft can’t come soon enough.

Obviously the plane had issues getting off the ground. Probably because it was too heavy. Typically, pilots calculate a speed beyond which they can no longer safely abort the takeoff. Beyond that speed, the plane is basically going to fly or shoot off the runway and crash. That point is decided based on weight, wind, runway length, etc. It's entirely possible mistakes were made with that or with loading the plane. Maybe there was some wind shear as well, which could explain a sudden drop or unexpected challenges getting off the ground.

Usually the co-pilot's job is to call these speeds out and if either of them calls to abort, there is supposed to be no discussion or debate on this and pilots are trained to act right away because every second counts. Obviously that did not happen

So, the pilots were not aware of issues before the abort speed (or they should have aborted) and committed to getting off the ground. I'm sure the in cockpit recordings will be part of the investigation. They sort of succeeded in the sense that they hit some objects but ultimately did not crash and got off the ground. Their climb rate must have been terrible. Usually the gear comes up as soon as you have a positive rate of climb (reduces drag). I imagine they called gear up seconds after leaving the ground before they hit anything even and the gear was likely transitioning.

Wind shear could have caused enough change in airspeed to cause the plane to not climb or even descend a bit. A heavy plane would have used up most of the runway in any case.

They then proceeded with what looks like normal procedure to get to altitude. Presumably they would have almost climbed out and changed frequencies from tower to local traffic controllers after 20-30 seconds or so. Recordings of that are going to be interesting. Presumably the damage to the ILS equipment would not have been noticed right away on the ground and people would have needed some time to figure out what the hell happened and what caused it and what plane hit it. Likewise the damage to the wall would not have been reported right away. By then the plane would have transitioned out of their area.

The question is whether the pilots noticed that they hit any objects and what the communication was with these controllers on this. The plane would have been pitched up (restricts visibility to the ground in front of you) and the damage occurred pretty far behind the pilots. So they may not have seen the obstacles immediately in front of them or heard/felt hitting them. These planes are big and heavy and there's lots of noise and vibrations when a plane takes off.

The damage looks dramatic but you wouldn't be able to see it until after the landing. Obviously the plane was flying and climbing and cruising normally. And they also landed safely. So flight operations seem to not have been directly affected. So, I can see them concluding that they had a stressful takeoff but had gotten in the air successfully. Then some time later they got the news that they hit some obstacles and that there is probably damage to the plane.

The big question is why that took 3 hours. I imagine it involved a lot of communication on the ground.

22 years later!

Worst single-aircraft disaster in history.

There's no reason the aircraft can't be properly repaired, and be as strong as it was when it was delivered. The Boeing Structural Repair Manual is very precise. It was just ignored.

I thought that on airliners pilots input runway length, altitude and wind strength and direction, and the computer optimized the thrust accordingly?

Usually in times of partial emergencies, there is a threshold point where you full own the emergency and declare it.

Also, the airport wasn't good anymore. They had just destroyed the Instrument Landing System at the end of the runway. Nobody should land there.

https://twitter.com/shukla_tarun/status/1050581391828836352

https://ichef.bbci.co.uk/news/624/cpsprodpb/C99D/production/...

As far as I can tell this wasn't unusually close to the runway, the plane just stayed on the ground far past the end of the runway.