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Comment by tempnow987 | Hacker News Reader

As soon as I heard the plane was "unresponsive" to controls I immediately though pilot error just because how unlikely a plane is to be actually unresponsive to controls.

Edit: Wow - reading the report I see they got to a 24 degree pitch angle on go around? That seems high, I thought you topped out at 15 or so. This is Air France stuff all over again with the pitch up into a stall etc. I'd love to know how experienced the FO was.

"Eventually a point is reached whereby any further increase in angle of attack does not produce an increase in lift, and this point is called the stalling, or critical, angle of attack. Each airfoil has a different critical angle of attack, but with typical general aviation airfoils it is roughly 16 to 20 degrees. "

Pitch and AoA are different, but during a landing / go around you are in a low speed regime and it just seems like pitching to nearly 30 degrees nose up is excessive. Is that Air France's standard go around vs 10-15?

The true story might be that the captain saved this plane with his nose down inputs.

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It really differs per plane, jets pitch up higher than typical general aviation aircraft during rotation and go-around. The 737 for example will command 15 degrees pitch up on the flight director when going around. If you did that on a typical general aviation trainer aircraft you would stall. We teach for example 7 degrees on the DA42 which is a typical multi-engine trainer for future airline pilots.

In a jet you'll pitch up to 15 degrees initially, reduce flaps (if landing flaps were selected, for example from 30 back to 15), then once climbing you'll retract the gear. At that point you're going to have to pitch up much more than 15 degrees if you don't want to overspeed. It all happens much faster with two big jet engines compared to an underpowered general aviation plane.

Especially if the crew thought they had an emergency and went full power combined with a light fuel load, you would expect a serious pitch up to avoid overspeeding the flaps.

Thank you! Extremely helpful.

Yes, on a small GA going to +24 degrees on a go around really jumped out as high, especially if you were starting low and very slow (on landing not uncommon). But I have zero big twin knowledge.

I wish they'd included a speed plot to go with the pitch plot. The plot does show what looks like full power. Given flight duration fuel would have been way down so plane would have been (relatively) lightish most likely.

> At that point you're going to have to pitch up much more than 15 degrees if you don't want to overspeed.

What's the risk of overspeeding? Can you actually reach speeds that are dangerous to the engines while climbing?

The problem is that the mechanisms that hold the flaps in place can be damaged resulting in loss of control over the surface. Sometimes a flap on one side of the plane will be damaged and, when you go to retract the flap, the plane will start to roll. Also the flaps can be torn off the plane.

The engines will be fine, but the airframe has a maximum speed in each configuration. For example the gear can't move above a certain speed and can't be down above a higher speed. Similar for the flaps, at a 30 degrees landing flaps setting you have a fairly low maximum speed. Have to retract flaps to be allowed to accelerate further without damaging them.

How would it be reaching such a high pitch angle with two opposite inputs on the controls? Doesn't that mean one of the pilots is still trying to increase pitch?!

Also it seems crazy that a modern aircraft can have pilots silently fighting one another for controls without realizing it. If standard practice is to have only one operating the controls at any time, why not a switch that enforces input from only one set of controls?

Or an alarm that says “hey, you’re fighting over the controls!”

I guess that's because the flying pilot might become incapacitated at any time (i.e. stroke, heart attack, ...), and then the other pilot has to take over as quickly as possible, and an additional switch that they have to locate and flip would need more time than just moving the controls?

In that specific plane, both control columns are physically connected. Moving one will move the other and controlling both will make you physically fight over the controls>

There is a safety feature where if you put enough force on one control column, you can break this linkage. You then have independent control, but the left column will only control the left ailerons and the right column only the right aileron. I assume the second case happened on this flight, but I cannot be sure.

There is no such switch or alarm because for Boeing planes, that's how they are built. The left column connects to the left wing, the right to the right, all via cables. In order for one column to control both, there have to be cables connecting them

You're thinking of older Boeing designs. The 777 is fly by wire.

Woops, I am indeed, thanks for the correction

That is exactly what happened to Air France flight 447 (two pilots operating controls in different directions)

(https://news.ycombinator.com/item?id=31193445)

Airbus planes DO have a button you can push to override and claim exclusive control through your "joystick". Otherwise, at least in normal control law I think, it averages the inputs.

There is still something weird going on with the inputs though isn't there?

How could the first officer be confused by the 7° bank angle even though he was the only one flying the descent?

Important also to remember that after the FO, who was pilot flying, first expressed surprise that something didn’t seem right, the period of confusion lasted only about ~45 seconds before the captain confirmed that he/she had taken command. Quite a long distance at about 130kts but not a long time in human problem solving terms.

> Pitch and AoA are different

Is pitch the angle of the wing, and AoA the angle of the wing relative to the fluid across the wing?

Yes

Pitch is the angle of the plane rather than that of the wing.

If the angle of the plane and the wing aren't the same and fixed relative to each other, you're probably already in thoroughly deep shit.

The only plane that ever went into production where the angle of the wing could be changed relative to the angle of the fuselage (other than on the way to the crash site) was the F-8 Crusader [0].

GGP post has it correct.

[0] https://en.m.wikipedia.org/wiki/Vought_F-8_Crusader

Except on stunt planes (and maybe fighter jets?) that are designed to fly upside-down a significant portion of the time, the wings are angled relative to the fuselage. Otherwise the whole plane needs to be in a nos-up attitude even for flying at a constant altitude, which would not be fuel-efficient because if the high drag.

The difference between the pitch angle of the plane and that of the wings is indeed fixed in any normal aircraft.

I've blacklisted Air France ever since the Damascus incident and their financial decision to attempt to divert over a war zone to Jordan rather than fly to a nearby safe location in Cyprus or Israel, especially when the company overrode the flightplan (which was to divert to Larnaca)

I'm willing to forgive the decision to not land in Beiruit on a flimsy pretext in the first place, but to not divert to Larnaca shows unforgivable decision making.

>The true story might be that the captain saved this plane with his nose down inputs.

Or the AoA was a product of the other pilot over correcting from what they thought was unintended nose down behavior. Hard to say, clearly bad procedure either way though. It's why there's clear protocol regarding who is in control of the plane.

The issue is that the REALITY was the plane was going very nose up at low speed. That is THE situation that gets you into a stall / spin situation.

Close to the ground in the pattern most folks in the US are taught to be very careful about this. Ie, when you are low and slow, don't go for a big pitch up or a steep bank. There isn't time to recover.

That said, I've got NO clue about 777's, so maybe a 25 degree pitch up on takeoff / go around is normal. Hard to imagine aerodynamically that working.

> Close to the ground in the pattern most folks in the US are taught to be very careful about this.

What makes you think it's taught differently outside of the US?

Can confirm in Europe. We don't even get taught much spin recovery, just spin avoidance, seeing that a spin can't be recovered from within final altitudes anyway

I believe Air France does their flight training completely different from the US. Here we have a healthy civilian flying culture (this really applies to the americas in general). Lots of stick time with manual controls (vs fly by wire). The French get lots of simulator time and are taught flying is more of an exercise in supervising the flight computer.

For now. The French are just ahead of the curve.

> healthy civilian flying culture.

I wonder if this is sustainable. The era of affordable general aviation aircraft is over, people are flying 50 year old planes because the new basic cessnas costs $400K each.

That doesn't seem like that much if split with 4 people over 15 years.

If four people need fifteen years, or one person needs to be a successful forty- or fifty-year-old neurosurgeon, to afford owning and operating a Cessna 172 - what effect do you think that has on the commercial pilot training funnel?

> what effect do you think that has on the commercial pilot training funnel?

It'll be fine regardless, there'll be no shortage in the military -> commercial pilot funnel of the most militarized country in the world.

That's fair. Too, I suppose it's not reasonable to assume we'll remain able to afford widespread civil aviation once we're no longer able to afford the world's most luxurious war machine. In that case, we won't need so many professional pilots anyway.

That has been true, but the military is rapidly drawing down their manned aircraft fleet. I would expect commercial airline pilots to increasingly come from private flight schools in the future.

https://www.thedrive.com/the-war-zone/units-flying-f-15c-ds-...

These aren't large numbers compared to stuff like transport, for both cargo and airmobile force components. You replace manned combat aircraft with remotely operated ones because you're at the point where that's the next thing you need to do to stay in the race, but that's not a race transport aircraft are running.

The overwhelming majority of military aircraft aren't fighter jets, they are transport aircraft - and are also a better proxy for civilian aviation.

No the Air Force has far more fighter jets than transport aircraft.

https://www.airforcemag.com/article/2021-usaf-ussf-almanac-e...

I stand corrected.

Likewise, but now I'm wondering how they compare in terms of total flight hours by type.

Granted, this is transparently an attempt to recover some remnant of a meaningful argument from the wreckage of the one I was trying to make, but it might still be interesting for someone more familiar than I with where to find the relevant data.

Transport pilots fly only slightly more hours than fighter pilots.

https://www.airforcetimes.com/news/your-air-force/2018/03/01...

Oh, well, it was worth a shot. Impressively quick followup!

I'd guess absolutely no effect at all; I don't think that kurupt213 was trying to suggest that commercial pilots commonly buy planes, and indeed I don't think it's true. I'd guess that the vast majority of commercial pilots have never owned a plane, and that small plane ownership is not at all a part of the commercial pilot training funnel. I actually think this whole subthread mistook "civilian flying culture" to be talking about general aviation when he was talking about commercial airlines (as opposed to the military).

No, but I think you may have the arrow of time reversed here. The argument in its essence - not that I'm reading GP's mind, nor need to, as the argument is not novel - is that, with access to general aviation as narrow and difficult as it's become in the past five or so decades, commercial pilots will still learn the technical aspects of operating a commercial flight during their airline-provided training, but rarely have much opportunity to learn how to fly, that is, to develop the intuitive understanding of aerodynamics and aircraft behavior that can enable a pilot to react correctly and without excess need for thought in situations and circumstances where that can make the difference between life and death for everyone aboard their aircraft.

Whether or not I fully buy the argument, I don't suppose I know. I do know that a lifetime of reading, study, and home simulation taken together taught me less about what an airplane does when it's flying than did one fifteen-minute discovery flight in a Piper Archer. It's different for professionals than for an aviation-nerd amateur, of course. But I see no reason in principle to assume there aren't things you only really learn from spending enough time flying a plane too small and simple to lie to you, and every reason from experience to assume that there are.

(Having just seen your edit, I'm no longer sure this qualifies as a response on point, but I'm going to let it stand and finish my supper.)

They don't need 15 years because they can get financing and take ownership of the plane for a 20% down payment.

80k downpayment + $2200/month sounds just as inaccessible as a 400k lump sum. That’s before fuel, maintenance, storage and operation costs…

> If four people need fifteen years, or one person needs to be a successful forty- or fifty-year-old neurosurgeon, to afford owning and operating a Cessna 172 - what effect do you think that has on the commercial pilot training funnel?

Little, because you don't have to own a plane to fly it; the commercial pilot funnel comes through private flight schools and military aviation (over time shifting from the former from the latter), not mainly from I-bought-a-plane-with-cash non-commercial private pilots.

Yeah, but do I learn more from a program of study at a private flight school, or from that plus having grown up flying the plane my folks bought when I was five, because it was that or a speedboat and Mom doesn't trust the water?

Not that this is me - if nothing else, you probably can't get my mom into an aircraft even at gunpoint - but it is more like the question that wants to be considered here.

I'm not sure what you're asking? There are a few commercial airline pilots whose parents owned airplanes, but those are rare. Most got their required flight hours either in the military, or by training in private flight schools and then working as flight instructors themselves.

> training in private flight schools and then working as flight instructors themselves

Who attends those private flight schools? Unaffordable aircraft obviously won't improve things and seem quite likely to make things worse.

I believe the "bootcamp followed by effective indenture" model has been widely favored among the regional airlines that act as feeders for the big players, dating back well before the software industry first happened upon it.

If I recall correctly, Patrick "Ask the Pilot" Smith has had some things to say based on his own experience here. In any case, whether or not that model is actively used today, I would be entirely unsurprised to see it spread widely in the next couple of decades, and maybe not only in the airline industry.

Aircraft rental fees are the most expensive part of getting an ATP license, but all sorts of people manage to afford it. They get support from parents or work other jobs or take out loans. Midway through the training program many of them get a CFI license and then work for the flight school training new pilots, which helps defray the cost of building up the necessary 1500 flight hours.

At some point the pilot shortage might get severe enough that airlines have to hire pilot trainees with little or no experience and then pay them to go through a training program. So far that hasn't been necessary but it's a common model in other countries.

Just how high class of job do you think commercial airline pilot is, exactly?

The point is exactly that owning a small airplane has not always been the signifier of necessarily enormous wealth it is today, and that it's worth asking whether that has had a deleterious effect on the ways in which commercial pilots learn to be pilots at all.

I suppose the larger discussion is properly around the vast increase in income inequality over recent decades, and I'd have done well to contextualize it there before now.

(In my defense, I've had such a day that the early root canal appointment, which played out like something from Marathon Man - not that my dentist is less than excellent, but I'm glad I already knew that because we had about half an hour there during which the least surprising thing in the world would have been for him to ask me "is it safe?" - that was the second most significant thing to happen since the sun last rose. So it's quite possible I am bringing less than my best to this discussion that I'm using to help me wind down toward sleep.)

https://www.bloomberg.com/news/articles/2022-04-23/u-s-airli...

But the point of general aviation is that it should be affordable as a personal hobby for a significant amount of people. tbh, I've actually considered owning a plane but dropped the idea entirely after realizing the only really affordable option is 50 years old and I don't really want to fly something that old.

I see a listing here for a 50% ownership stake in a 2005 Cessna 182T Skylane for $180k. Financing is available for 20% down. With financing, the listed monthly price is < $2k. That seems somewhat reasonable to me. https://www.controller.com/listing/for-fractional-ownership/...

This is a real HN comment. $2k a month for a hobby (before gas, garage, fees, ??) is nothing but a dream for most people.

Yes but where is that idea coming from that flying needs to be cheap enough to be a hobby?

I think the point is that it used to be much more affordable than it is today, and GA is quickly becoming the exclusive domain of the 1%.

That's not even the dominant cost -- the running costs are ~$150-200 per hour in addition. That covers fuel, maintenance, inspections, parking, insurance, prop overhauls, and accruing for an engine replacement every 2,000 hours.

> But the point of general aviation is that it should be affordable as a personal hobby for a significant amount of people.

Why?

For starters, it's called general aviation.

>people are flying 50 year old planes because the new basic cessnas cost $400K each

This wasn't always the case though. There's a chapter in the book Where is My Flying Car? that explains how this was a result of the early 70s explosion of product liability regulations + a FAA that was and continues to be completely apathetic to general aviation

Most people that want a new aircraft for GA for less than 6 figures are kit building them. Also there’s the “sport” flying market and ultra-light market as well.

Building a kit airplane is probably not going to save you any money when you consider the space, time, and skill needed.

That's the same price as new 40' boat - which seems about right.

Yes, but if you can't afford a 40' boat you can always go with a 15' one, or a skipper with cost on par of a large vehicle. Jetskis are even cheaper.

Yeah, that’s the stereotype of the fighter jock or, as someone on HN once put it, „fixed-wing enthusiast“. A man (always), flying with enthusiasm, intuition, not too much alcohol, direct controls etc.

It’s bullshit, of course. The archetype, if it ever existed, has been in decline since 1945 at the latest. Within that time, miles traveled have increased 15-fold, accidents have been reduced by 95 % (for a combined risk reduction of factor 300) while costs have come down by 80 %.

The adrenaline junkie will get bored and kill everyone with carelessness or controlled-flight-into-terrain. Because the total number of exciting situation in your 30 year career is, to a near approximation, zero. A good pilot today is a bureaucrat, meticulously running through checklists day after day.

There was at some point a philosophical split between Airbus and Boeing, the former going for fly-by-wire including automatic modification of pilot inputs etc., while Boeing was culturally invested that archetype of a pilot and preferring more direct controls. The outcome: no discernible difference in the safety records of these supposedly different approaches. Pilots from very different backgrounds? No difference. What matters for safety isn’t character, it’s process. And that’s great because processes scale, natural-born aviators don’t.

Newer Boeing models including the 777 are also fly-by-wire.

> I believe Air France does their flight training completely different from the US

Why do you believe so? Honest question.

No idea how true this can be. I know only one airfrance pilot but he did regular civilian flying school and flied for the french Army before applying for Air France training. Memory is blurry but I think at the time he needed some creds from previous flying experience to apply.

Hang on a second, are you suggesting that you can get a commercial licence in Europe by flying simulators?

I don't know about France (but Europe tends to be aligned), but a basic commercial license in the UK requires 200 hours of flying experience. On top of that you would need a multi-crew rating, an instrument rating a multi-engine rating and a type rating on the plane you are going to fly. Enough to recognise that pushing the yoke left makes the plane bank left.

My brother wanted to be a pilot and was looking at moving to the US because it is cheaper and has more consistent weather. He also told me the licences were easier to get than in Europe. I think you have fallen into the 'US is best trap'

> He also told me the licences were easier to get than in Europe. I think you have fallen into the 'US is best trap'

He has, and yes European licenses are tougher.

Indeed, to get a license in France, you actually need to fly, but I still think US pilots are among the best, but that's because the US has a stronger aviation culture.

AFAIK, a typical path for a pilot in the US is to start taking lessons in a small plane, then, after getting the private license, make money flying, typically as a flight instructor, in order to pay for flight hours in bigger planes. The result is a lot of flight hours as a pilot in command. Hours as a flight instructor are particularly important because you have to cover for your student mistakes.

In countries with a weaker aviation culture future pilots tend to go to flight schools where they do the required number of hours and pass the tests but nothing more. There is simply not enough demand for general aviation flight instructors. The number of flight hours may be significant and the tests hard, but they fly mostly as students, not as pilots in command. So while they may know the technique and procedures, they lack the experience of being in charge of the plane.

I'd say that France is not the worst in that regard, we have many "aeroclubs", but not as good as the US.

This is utter nonsense.

In the US you can't become a flight instructor with a private pilots licence. You have to pass your commercial licence first. Just like in Europe.

You have to do at least 100 of your hours as pilot in command in the UK to get your commercial license. You will have to finish that before you can be an instructor. You can't make money from flying until you have finished your commercial licence.

To be an airline pilot you will need to have flown 1500hours in Europe or the US. Nobody gets there because of culture, they get there by flying 1500 hours

The US has better flying weather so you can build his more quickly, is cheaper and because there are more trainees there are more opportunities to build hours at someone else's expense. But cheaper does not mean better.

> I believe Air France does their flight training completely different from the US. Lots of stick time with manual controls (vs fly by wire).

I'm sorry, but I call BS on what you are implying here.

First, post 9/11, most European airlines killed off their Ab-Initio programmes.

Therefore for most European airlines, the only route to getting a seat in the pointy end is the so-called "Direct Entry" route. This either requires pre-existing civilian qualifications and experience (i.e. unfrozen ATPL with real-life hours in the bag), or otherwise being ex-military with equivalent qualifications and experience in that world.

For the few airlines that do offer Ab-Initio, then I'm afraid it's complete BS if you think ab-initio trainees for any European airline just get dumped in a simulator and trained how to follow the magenta line. They will follow the same route as anyone else, i.e. they will be sent off to the US or Australia (because of the consistent weather, not anything else) and will work their way through the usual route SEP -> MEP -> Hours building .... they will then come back to Europe and finish off by getting an EU license. Only once they've got their commercial qualifications and have built experience will they then start Line Training which is where things like MCC come in, and that's where sim time starts coming in.

Simulators are expensive to run, even more expensive to buy, and there are not many of them around. They typically run 24x7 and are used for refreshers for existing crew as well as training new ones. To think there's enough spare capacity floating around to train green newbies from zero is a pipe dream.

Finally, on a practical note the newbie in the right seat will always be paired with a more experienced captain in the left seat. You will never find two noobs up front.

what i wrote was the reasoning given for the Air France Brasil to Paris flight. You remember, when they stalled a perfectly good AirBus 350 and dropped it from cruising altitude into the Atlantic.

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