Hacker News Reader

Comment by Tepix | Hacker News Reader

Did they know in advance that they were having problems?

Edit:

Answer: Yes

... the crew initiated a go around due to a unsafe nose gear indication, climbed to 4000 feet and entered a hold to work the checklists. After working the checklists the crew declared emergency and requested emergency services on stand by. The aircraft performed a low approach to runway 36L, positioned for another approach to runway 36L and landed without nose gear extended at 08:54L (12:54Z) about 12 minutes after the second go around and about 30 minutes after the first go around.

View on HN

There is an algorithm for everything in aviation. If you suspect your landing gear is not functional, you typically fly by a tower and have them make visual confirmation. Then you have another algorithm (they call them procedures) for how to land without gear. The airport likewise has a checklist of everything to do in this case. All of these procedures are hard won, the NTSB uses every hull failure and fatal accident to analyze what went wrong and how to create a better procedure.

> There is an algorithm for everything in aviation

This is how I got my commercial pilot's license, and I'm a senior software engineer.

It just "clicked" with my brain to follow specific procedures ("algorithms") for absolutely everything. Checklists, strict rules, "flows", handling emergencies. It all felt natural to me.

They will throw random stuff at you during checkrides. Pull the power back on one of the engines right after takeoff saying it failed, fail instruments that you were using to navigate, blindfold you ("foggles") and put you almost upside down and then say "recover!".

But you have everything so ingrained in your mind by that point that it's almost robotic. You just look at the inputs (almost upside down, engine #2 is gone, no attitude indicator, whatever it is) and know what the output is supposed to be (roll to unload Gs, lower the nose, full power, check the standby AI, etc).

I happen to work well when there are strict rules and procedures. If this, then that.

I got my CPL the same year my first kid was born. The procedure/checklist culture transferred really well between baby tasking and training.

When you are robotically rolling to unload Gs does it still make your heart go boom!?? I love the idea of flying. I see crop dusters and private planes flying in all the time and it makes me wonder if I ought to try it out.

My Private Pilot training was almost 30 years ago, but after a while it stops being exciting. And that was a big part of why I dropped out: it had become about as interesting as driving in rush hour traffic.

Like the situation OP says: you scan instruments to analyze the situation, determine what to do to recover and apply that procedure. If it doesn't work, or something else goes wrong during that procedure, you adapt to another procedure. Remember, that during every flight with an instructor, you're being trained on one thing or another, so after a while all the "emergencies" seem routine. You'll be turning onto Final to land and suddenly your instructor will decide that your flaps failed so you have to land without them, or just as you're flaring for a landing he'll tell you to go around, etc.

It certainly results in well-trained pilots, but it also gets very boring.

That's why I like gliding more. It's really all seat of the pants. Not dominated by procedures and endless circuit practice.

I once loved the idea of flying as well, and I have a miserly 18 flight hours on my record, accumulated 23 years ago.

The immediate reason to stop was the fact that the more I did it, the more nauseous I got, but by then I had already decided that flying was not nearly as exciting as I expected it to be. Stopping was an easy decision to make.

That said, I also have friends who still totally love it.

And when there is not a tower nearby, you, uhh... find a way. My buddy was flying into one of the many uncontrolled airports in NorCal, and there was a guy in a single-engine retractable gear circling the airport. When Buddy made his downwind call, the Guy radioed "Hey I'm not getting any indication whether my gear is down or not, can you fly by me and tell me if it's down?" It was down, so Guy ended up attempting the landing with a bit more confidence than he started out with.

I was on a commercial plane where the pilots could not tell if the gear was completely down and locked and got someone on the ground to look as we flew by slowly at low altitude. It appeared to be down, but they still landed very gingerly. Thankfully it was fine.

I recall a mid air collision that occurred that way once. I forget the exact crash name, but IIRC a civilian aircraft was trying to spot for damage on another aircraft and they got too close.

Not that people shouldn’t help but you gotta be careful with maneuvers you don’t typically make, even if trying to be helpful / are a pilot.

That rings a bell... I think the civilian craft was a helicopter, but my google-fu ain't finding the incident.

> There is an algorithm for everything in aviation.

In fact there's an exception that proves that rule: there was not an algorithm to handle pitot tube ice causing an MCAS failure on the 737 MAX, because the type certificate was shared with earlier aircraft that didn't have an MCAS to fail.

And two planes crashed because pilots didn't have an algorithm to follow to tell them what was happening when their trim went crazy.

> you typically fly by a tower and have them make visual confirmation

I've been wondering for a while when I read stuff like this, why don't modern airplanes have exterior cameras that cover every surface? I watched a video recently about a flight where one of the engines literally detached and the pilots didn't know the extent of the damage until after. Why not just have cameras they can quickly pull up to check stuff like this?

Not saying this should be an alternative, but having read a lot of transcripts and video of things like this, I wonder why there aren't outside cameras that would potentially give pilots a visual indication of plane conditions outside? Is it just the cost of supporting resilient cameras?

A lot of incident reports have flight attendants or copilots leaving to try to make visual confirmation of things that it seems would be better suited if there were some actual visual feedback.

You'd gain nothing, they can already see it with their eyeballs, and they don't require anything else like faster response or a different viewpoint. You'd lose in terms of putting another hole in the aircraft and maintaining another system, and you'd still need the manual procedure in case the camera didn't work.

>and you'd still need the manual procedure in case the camera didn't work.

And presumably if the camera doesn't work as part of the pre-flight checklist for whatever reason, you're not going anywhere until it's fixed/replaced.

camera would probably just get an INOP sticker put somewhere, a surprising number of things can be nonfunctional on an airplane before it's grounded.

part of it is that there's a backup for most everything required.

> You'd gain nothing, they can already see it with their eyeballs

I'm talking about things they can't see, which I've heard in recordings as well.

For something like this they'd gain something for sure - time and redundancy

Why is the current time and redundancy requirement insufficient? They had plenty of time and opportunities to look at it, and they succeeded with time to spare. What is the scenario where they would run out of time, and why couldn't they land assuming that the landing gear wasn't deployed?

You'd need potentially an unrealistic number of cameras. Even if you decide on a case by case basis, you still have to weigh the risk that every component adds, and with a finite amount of money to spend on risk reduction you want to get the most bang for your buck.

> Why is the current time and redundancy requirement insufficient?

I'm operating under the belief that more time to respond to issues is always a plus. Do you disagree?

More time to respond is a plus. Adding hardware is a minus.

Good enough is good enough.

> Adding hardware is a minus.

It's a cost, which is why I'm trying to understand what the ROI would be.

> Good enough is good enough.

In cases like this, yes, but ... planes do crash due to mechanical failure and it's not unusual for there to be confusion from instrumentation where visual confirmation could help.

I'm sure there are at least a few camera placements that would be worthwhile.

To answer your earlier question, not to split hairs, but I disagree with "always". You can inadvertently increase risk when trying to reduce it, or unwittingly prioritize things that offer less bang for your buck. That's why risk analysis is important.

I don't disagree that adding data can increase risk. I'm just not seeing the argument against exterior cameras.

I think it's probably just considered not worthwhile enough at the moment. We'll probably get them one day. Rockets have cameras, after all.

I want to be clear I'm agreeing with you that some cameras would be useful in general. I think my only disagreements are that eyeballs are fine for this scenario, and that "more" isn't always meaningfully useful or necessarily better.

....how can they see the area where the front gear is from within the plane?

The people in the airplane ask the people on the ground to look at it for them. "They" refers collectively to pilots, flight attendants, and air traffic controllers.

The pilots "see" it with sensors.

The tower sees it with a set of binoculars. Hopefully.

A lot of aircraft could do this but the rules are most likely the same for the majority of air planes large and small.

Newer aircraft have external cameras that can be pulled up on screens in the cockpit.

They don't have onboard cameras with eyes on the front landing gear mech? Why not?

If you want to hear the conversion between the pilots and ATC during this time, the VASAviation channel has you covered:

https://www.youtube.com/watch?v=Y7bWWVj91YA

I find the YouTube ecosystem amazing. If there is a popular niche topic that has at least some amount of following, you’ll find several “competitor” channels.

VASAviation is one of the “air traffic control recording” YouTube channels but there are a few others that are equally as good.

There are at least two YouTube channels[2] dedicated to recording the crazy boat ramps around Miami. Nothing is more entertaining than watching all the chaos around a boat ramp. Especially ones are busy as those around Miami.

There are dozens of channels publishing multi-hour first person view trips from rail conductors traveling through various scenic rail lines[3]. Some get 100’s of thousands of views per video! I wonder what fraction of that traffic watches the entire trip!

Let’s not forget Australian jetters [1]! You too can watch at least two channels worth of drain cleaning videos complete with all manner of foul disgusting water bubbling up out of random bits of pipe. Kids love this stuff!

These channels publish frequently and get a reasonable amount of watches. It’s nuts how a platform like YouTube can grow such strangely niche channels.

1: https://youtube.com/@DrainAddict

2: https://youtube.com/@MiamiBoatRamps

3: https://youtube.com/@RailCowGirl

For those interested: the video lacks a lot of audio, since not all frequencies are/were recorded. I think the most interesting stuff is missing.

For context: passenger jets have a positive feedback system that indicates to the pilots whether or not the gear is in the correct position. When they operate the control to raise or lower the gear, there are corresponding indicator lights that confirm whether or not the gear has successfully moved to the commanded position. Part of standard procedure is to lower the gear, and then verify that all of the indicator lights confirm that the gear has successfully moved into the correct position. If they are not working properly, it is apparent from the indicator lights. They will then know that they will have to abort the approach and run troubleshooting checklists for that particular issue.

On of the more evocative things (esp. for those in the UK) was a Spitfire helping out a Vulcan (XH558 no less) with nosegear issues in 2015.

https://theaviationgeekclub.com/that-time-a-wwii-spitfire-he...

Reply on news.ycombinator.com