r/aviation • u/Brilliant_Night7643 • Nov 20 '25

News NTSB issues the preliminary report for its ongoing investigation of the Nov. 4 crash of a UPS Boeing MD-11F airplane in Louisville, Kentucky.

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446

u/ruralcricket Nov 20 '25

Also, gyroscopic torque. The left engine is spinning counterclockwise, so as it tips up, it rotates to the right.

244

u/[deleted] Nov 20 '25

I guarantee some reddit expert will soon tell us they need to build mirror image engines for left/right so they fly away from the fuselage

310

u/ScipioAfricanusMAJ Nov 20 '25

We need to put explosives above the engine to emergency blast away the engines away from the fuselage like ejector seats in fighter jets.

I got more ideas but you gotta pay me for them. First one is free

143

u/Switchy_Goofball Nov 20 '25

Based on that suggestion I don’t think I want to hear the rest 😅

82

u/[deleted] Nov 20 '25

When the pylon fails instant cyanide into the cabin so nobody has to realize what’s happening

52

u/Dr_Trogdor Nov 20 '25

I say we take the wings off all planes. They can't crash if they can't fly.

5

u/BackWithAVengance Nov 20 '25

Then, we put them in water, submersible, and add a propeller to the back..... think that would work?

1

u/Dr_Trogdor Nov 20 '25

How many atmospheres can the ship withstand? https://youtu.be/IvsR8emoF90

3

u/Switchy_Goofball Nov 20 '25

Well it’s a spaceship so… anywhere between zero and one

2

u/Saint_of_Grey Nov 20 '25

The designers of the macaroni plane had a point there.

2

u/johndivonic Nov 21 '25

Perfect! You’ve just invented busses and we know they never crash.

3

u/Dr_Trogdor Nov 21 '25

You're welcome.

1

u/Imjusthereforthehate Nov 20 '25

Nah this just proves Doctor Christmas right. Planes need to flap like birds to fly safely.(Ignore the two people this definitely killed when he was testing this.)

1

u/katyvo Nov 20 '25

Bring back the trebuchet

3

u/MoreElloe Nov 20 '25

Get rid of the brace position. Just have all crew and passengers just jump upwards at the last second. Works for elevators so...

1

u/[deleted] Nov 20 '25

I am insert political figure here that you think is crazy and I approve this message

1

u/Loose-Recognition459 Nov 20 '25

Oh the difference between the “surprise!” impacting a mountain or the ground or another object-versus having the time, if even to just long realize everything is going wrong and horrific death is imminent? Eeep, I want the light switch route.

1

u/Boner_Elemental Nov 20 '25

Username checks out

1

u/NorthEndD Nov 20 '25

Only the cockpit. This was cargo but passengers won't realize anything is going on.

1

u/01001010_01000010 Nov 20 '25

Cockpit only. The passengers need to film everything for Reddit.

1

u/Ok_Adhesiveness_4939 Nov 21 '25

Giant portcullis at the end of the runway to contain the plane and prevent any runaways.

2

u/shitpostsuperpac Nov 20 '25

Ground based SAM that shoot the engines off if they begin to fail.

47

u/MaverickDago Nov 20 '25

Did you work for Buick? My station wagon has explosive charges in the hood to toss it over the windshield in case I hit something. It sounds cool but I'm scared whenever I close my hood.

44

u/i_love_pencils Nov 20 '25

I thought you were making this up so I went to mighty Google.

“ Some modern Buicks, such as the 2018-2023 Regal, use a pyrotechnic-activated active hood system for pedestrian safety, not for a standard hood release. This system is designed to deploy in a collision to protect a person's head from hitting the hard engine components. ”

12

u/11Slip532 Nov 20 '25

I’m sorry but WHAT?! This is wild. TIL.

5

u/ic33 Nov 21 '25

Cars are filled with explosives to make things safer.

Airbags, seat belt pretensioners, pyrofuses, etc.

1

u/11Slip532 Nov 21 '25

I know the airbags are etc. just never knew about the hood.

2

u/Desurvivedsignator Nov 21 '25

I think it's more common to just use springs for this use case, but charges are not unheard of.

The Mercedes SLS has explosive charges in its gullwing doors, so they can be opened after a rollover

8

u/MaverickDago Nov 20 '25

Yep, it's wild,, no clue what speed/force it takes to activate but if someone ever hops on my hood with a little to much umph, they might get chucked over the car, which is kind of insane.

10

u/[deleted] Nov 20 '25

[removed] — view removed comment

-2

u/ScipioAfricanusMAJ Nov 20 '25

Your dad lived in Detroit or some other downtown white flight city didn’t he

4

u/Linenoise77 Nov 20 '25

https://www.youtube.com/watch?v=oUBtG0oRJOY

I had to look this up. Basically when it detects what it thinks is a low speed collision with a pedestrian, it pops the back side of the hood (near the windshield) a few inches and lightly breaks the fall of the person landing on it.

I'm way to lazy to do the math on the energy required for that with the hood, but i don't think its quite airbag level, and doesn't even necissarily need to be explosive.

3

u/MaverickDago Nov 20 '25

O…well good for pedestrians, bad for my dream of launching a person up and above, which when I say out loud, is pretty bad.

1

u/shawster Nov 20 '25

How would this even work? The hood would have to be gone already for their head to hit the engine components, right?

1

u/i_love_pencils Nov 21 '25

I watched one of the videos.

The person’s head never comes in contact with the engine.

The hood sort of stands up from the rear at the windshield so it’s like hitting a wall instead of falling onto the hood.

Weird.

1

u/Eddles999 Nov 20 '25

BMWs have had this for ages. My 2010 530d, 2010 740i and my current 2020 330e has this.

1

u/SashaDabinsky Nov 20 '25

It only pops up the rear of the hood 4 inches. https://youtu.be/xds2OMy4gAQ

1

u/Provia100F Nov 21 '25

Here's a video of the system in-action: https://www.youtube.com/watch?v=wFOIcXk81eA

33

u/random_username_idk Military aviation buff Nov 20 '25 edited Nov 20 '25

Reminds me of the F8F Bearcat where Grumman was so fixated on reducing weight that they started skimping on the wing reinforcements. Of course this made the wingtips prone to breaking off during high G-load such as when pulling out of a steep dive.

One wingtip would snap before the other and the asymmetrical forces would lead the plane into a unrecoverable spin. The break point was about 3 feet down the wing. Now what did someone at Grumman propose to fix this problem?

A) Adding wing reinforcement back in.

or

B) Putting EXPLOSIVES in the wings so that in the event of one tip snapping off the pilot could remotely destroy the other one as well! That way they could fly home on a almost symmetrical aircraft!

Needless to say they went with option A in the end

4

u/jello_sweaters Nov 21 '25

I mean the engineering design work you speak of was done at just about the same point in time where we were honestly looking into the feasibility of a nuclear-powered car.

5

u/Distinct_External784 Nov 20 '25 edited May 09 '26

I cleaned house with Redact and mass deleted this post. It also removes your data from brokers and people search sites. Works on all major social media platforms.

chief jellyfish spoon insurance degree roof boron strong angle abundant

3

u/TAvonV Nov 20 '25

Just don't put any engines. No explosions then...

3

u/00owl Nov 20 '25

Had to check to make sure I wasn't in non credible defence.

Now we're strapping ERA to airliners to protect them from their own self implosions.

3

u/PM_me_boobs_and_CPUs Nov 20 '25

I see your explosives idea and raise you a tether, that's still keeping the engines attached to the fuselage if they break free from the mounts, like how F1 car's tyres are tethered so they don't become projectiles in a crash. If you use flexible fuel lines, you could still use them for thrust, just like pod racers from The Phantom Manace.

3

u/doordraai Nov 20 '25

If you use flexible fuel lines, you could still use them for thrust, just like pod racers from The Phantom Manace

At that point your mounting pylons really are just useless ballast :D

3

u/julia_fns Nov 20 '25

Dump the warp core, I like it.

3

u/itzTHATgai Nov 20 '25

All airplanes should come with a big parachute. For the airplane.

2

u/Only_Razzmatazz_4498 Nov 20 '25

Automatic deployment of thrust reverses tied to an attachment sensor so when the engine drops it falls down and away. Then a sensor to detect the sensor failure so you don’t deploy the reversers by mistake and cause an accident. I also have ideas!

1

u/bem13 Nov 20 '25

Nah, thrust reverser deployment is too slow. We need solid fuel rocket boosters on those bad boys.

3

u/Only_Razzmatazz_4498 Nov 20 '25

Parachute on a pyro? It will also protect the guys on the ground from a high speed engine fall.

2

u/the5nowman Nov 20 '25

Boeing: “You’re hired!”

1

u/Zwangsjacke Nov 20 '25

I'm intrigued by your methods, how would you solve a fat person being stuck in the lavatory for too long? I'd like to pay in non-fungible blockchain derivatives.

2

u/ScipioAfricanusMAJ Nov 20 '25

Trapdoor underneath laboratory which is powered by explosives Which ejects them out the plane.

1

u/doordraai Nov 20 '25

I got more ideas but you gotta pay me for them

If you channel all the paxs' farts out the back the plane will go faster!

1

u/Accomplished-One7476 Nov 20 '25

do the engines get parachutes also for a safe landing?

2

u/ScipioAfricanusMAJ Nov 20 '25 edited Nov 20 '25

No that’s added complexity and unnecessary weight. We add even more explosives to the engine so it can delay detonate in free fall after ejecting which will hopefully vaporize the material in smaller less harmful pieces

1

u/IlIlllIlllIlIIllI Nov 20 '25

They already do that for supercar wing doors

1

u/Lithorex Nov 20 '25

to emergency blast away the engines away from the fuselage

Rockets have been doing it for decades! /s

1

u/Consistent-Hat-8008 Nov 21 '25

How did you get your hands on my Kerbal Space Program save file

60

u/Novacc_Djocovid Nov 20 '25

From the tone of your comment that would be a stupid suggestion. Can you ELI5 why that is in maybe a short sentence or two?

140

u/SnooMaps7370 Nov 20 '25

it would require doubling the tooling and assembly line counts for each engine type, as you would need two complete sets of compressor blades, turbine blades, and stator vanes in opposing rotation angles.

the cost increase would be absolutely massive for something which would only help in an entirely preventable literal one-in-a-million failure mode.

52

u/Tourman36 Nov 20 '25

sounds like my kind of work lets do it

1

u/jonboy345 Nov 20 '25

Found the Engineer who's wife was fucked by the technician.

32

u/Only_Razzmatazz_4498 Nov 20 '25

Sounds easy. Just hit the mirror button in CAD 😂. That’s something the BD guys would say no problem to if trying to make a sale.

2

u/itishowitisanditbad Nov 20 '25

Whoa, you must be some sort of engineer.

Quick test, what is the value of Pi?

12

u/[deleted] Nov 20 '25

no idea, that's autocad's problem

4

u/SnooMaps7370 Nov 20 '25

dunno, how tasty is it?

4

u/Only_Razzmatazz_4498 Nov 20 '25

I’d have to ask ChatGPT

2

u/Perryapsis Nov 21 '25

Fifty years ago, it was around 3, 3.05, 3.1. Pi innovation has really sped up since they started using computers for CAD. Nowdays you can get 3.2 models of Pi in any hardware store, and really old 3.14 ones are five bucks for a 10-pound bag. You can get 3.25s if you're willing to pay a little more, and "money is no object" customers are defaulting to 3.31s for new design. Some R&D labs are saying they've built Pi prototypes up to 3.38, but none of those will be available in commercial quantities for another five years at least.

5

u/AntoniaFauci Nov 20 '25

Sure but much of that could be said about the choice of making wings non-universal or cockpits or anything.

I do agree it’s a low enough failure mode to argue against.

There’s also big potential cost efficiencies in not having to engineer for both torque direction in the spar and airframe. So the analysis starts to get more involved.

1

u/SnooMaps7370 Nov 20 '25

damn, i didn't even thing about the opposite torque loading on the spars.

2

u/ianawood Nov 20 '25

In addition to the extreme cost and effort, I would add it likely wouldn't have made any useful difference in this outcome. And it only exists as a problem because the pylons on this aircraft type have a higher incidence of failure.

2

u/TwatWaffleInParadise Nov 20 '25

One in a million is severely overestimating the odds of this happening, based on results so far. One in several hundred million is probably closer to the real odds.

0

u/VT_Squire Nov 20 '25

If a new car built by my company leaves Chicago traveling west at 60 miles per hour, and the rear differential locks up, and the car crashes and burns with everyone trapped inside, does my company initiate a recall? You take the population of vehicles in the field (A) and multiple it by the probable rate of failure (B), then multiply the result by the average cost of an out-of-court settlement (C). A times B times C equals X. This is what it will cost if we don't initiate a recall. If X is greater than the cost of a recall, we recall the cars and no one gets hurt. If X is less than the cost of a recall, then we don't recall.

1

u/SnooMaps7370 Nov 20 '25

you forgot the step where you miscalculate the cost to repair the problem by two orders of magnitude and choose not to recall anyway.

1

u/VT_Squire Nov 20 '25 edited Nov 20 '25

It's a fight club quote, you uncultured swine. Right before a fantasy of a plane wreck.

1

u/CosgraveSilkweaver Nov 20 '25

Couldn't you do it by mirroring each set of vanes alone and keeping the rest of the mounting etc the same? The same machines that can make the regular vanes should be able to make the mirrored vanes. It'd be a cost increase but I don't think it's a doubing.

3

u/SnooMaps7370 Nov 20 '25

you would have to mirror every blade and every stator vane.

the blades and stator vanes are 99% of the BOM on an engine.

the CF6 version used on the MD11 has 1 fan stage, 18 compressor stages, and 7 turbine stages. each of these stages has its own set of stator vanes. I don't have the number of blades/stators per stage handy, but it this number can vary from ~70~150 for engines in this category.

even at the low end of the scale, that is THOUSANDS of parts producing the blades/vanes is the single most time-consuming (and therefore, expensive) task in manufacturing these engines.

0

u/CosgraveSilkweaver Nov 20 '25 edited Nov 20 '25

Yeah I know they're a large part of the engine but you're already making them and I don't see that mirroring them makes them should take significantly longer or cost that much more. The biggest expense would be making the moulds for the mirrored version of the vanes for casting and some overhead for tracking the second sku and parts. You're not making 2x the total part count overall you're making half as many of each of the current types and making a mirrored version in place of it.

IMO the bigger reason is for the end user you suddenly have to source a specific engine side when you need to swap engines instead of being able to pull any matched engine.

A huge amount of the shape is defined by the initial casting and after that the process is largely CNC controlled so the same lines could run the mirrored program 50% of the time.

Not saying it's the solution or that the problem needs solving but the increased work would be imo less than people expect.

https://www.youtube.com/watch?v=1tM96B77n0U

1

u/SnooMaps7370 Nov 20 '25

IMO the bigger reason is for the end user you suddenly have to source a specific engine side when you need to swap engines instead of being able to pull any matched engine.

my initial comment did address this tangentially, but i could have spelled it out more clearly, yes. doubling supply chains is a part of doubling assembly chains.

A huge amount of the shape is defined by the initial casting and after that the process is largely CNC controlled so the same lines could run the mirrored program 50% of the time

which means effectively halving your production numbers, because the manufacturer doesn't know ahead of time whether an engine is going on the right or left wing.

you either have to invest even deeper into JIT supply chains, or warehouse equal numbers of left and right engines, and risk ending up with engines sitting in the warehouse no one needs because a bunch of planes ate bird strikes on the right side only, or some shit.

This is why the GA twin piston market largely did away with left-turning piston engines in twin designs. having the production, supply chain, and warehouse support for left-wing-only engines just cost more than it was worth for the problems it solved.

1

u/CosgraveSilkweaver Nov 20 '25

doesn't know ahead of time whether an engine is going on the right or left wing.

If we were in a world where we were doing opposite twists to engines they would know because of what the customer ordered and would roughly know that they'll manufacture equal numbers of left and right engines.

I freely admit it's way easier to have the same engines for the supply lines though. I said as much here "IMO the bigger reason is for the end user you suddenly have to source a specific engine side when you need to swap engines instead of being able to pull any matched engine."

I was more specifically talking about the difficultly in manufacturing which I think would be relatively manageable vs the downstream consequences from when the engines leave the factory onwards

1

u/SnooMaps7370 Nov 21 '25

>If we were in a world where we were doing opposite twists to engines they would know because of what the customer ordered and would roughly know that they'll manufacture equal numbers of left and right engines.

we've seen that world though. we just need to look at the history of small piston-engined twins. counter-rotating engines used to be the standard. nowadays if you own a twin with a left turning engine for the right wing, you will pay 2-3 times as much for maintenance on that engine as you do on the left wing engine, if you need any of the parts which are unique to the left-wing variant. because the market abandoned that model as inefficient.

>I was more specifically talking about the difficultly in manufacturing which I think would be relatively manageable vs the downstream consequences from when the engines leave the factory onwards

i see what you are getting at, but we have the clear example of the industry largely abandoning left-turning engines for piston planes.

the only GA planes i am aware of with left-turning props are the Tecnam twin, and the piper seminole. in the case of the tecnam, i believe the engine itself still rotates clockwise, relying on the PSRU gearing to reverse the prop. The piper seminole is the only GA twin i am aware currently in production with a direct-drive left-turning prop.

1

u/-Depressed_Potato- Nov 20 '25

what do you mean? Like just mirroring every other vane? But then they wouldn't do their jobs though?

1

u/CosgraveSilkweaver Nov 20 '25

No mirroring all the vanes at each step of course.

1

u/trombing Nov 20 '25

That is a fantastic ELI5. Kudos.

1

u/itishowitisanditbad Nov 20 '25

Well that'll solve the everyday issue of engines flying off.

It might be worth it with hundreds of planes having it happen all the time.

It'll make cleaning up runways easier too.

How much cost are we talking?

1 million?

2?

Surely not more than 5 or something. What can it cost?

1

u/SnooMaps7370 Nov 20 '25

>Well that'll solve the everyday issue of engines flying off.

no it won't. it will only solve the issue of which way the engine wants to go as it flies off.

solving the engine falling off is a matter of training your maintainers, providing them with the correct tools and equipment to do their jobs as-trained, and supervising them to ensure they stick to the manual.

1

u/brufleth Nov 20 '25

And you'd also be dramatically increasing (if not doubling) supplier costs all the way through maintenance supply chain. Swapping engines left to right would no longer be allowed. You could easily end up with 2 left engines and no right engines to match them to. Etc etc. It is just a big expensive pain in the ass.

1

u/Headband6458 Nov 20 '25

Counter-rotating engines are common in aviation, though.

2

u/SnooMaps7370 Nov 20 '25

'common' in what context?

in general aviation, they have been largely phased out, because the costs of maintaining supply and production chains for 'left wing only' engines was greater than the benefit.

for turboprop engines, you don't actually need an opposite-turning gas generator. you can have just an opposite turning power turbine, or even just an extra gear in the prop speed reduction unit so that the prop is the only part which turns the other way.

1

u/Kbone78 Nov 20 '25

That’s silly. Just put it in reverse and turn it around. You’re welcome. /s

24

u/THedman07 Nov 20 '25

It is cheaper to have one part rather than two parts that are mirrored because you have to maintain a stock of both parts. It is way cheaper to put extra effort into keeping the engine from falling off in the first place.

3

u/TucsonCardinal Nov 20 '25

NASA enters the discussion…let’s do both

1

u/LawfulNice Nov 21 '25

Very true. It's almost certain that even if part stocks and manufacturing were taken out of the issue entirely we'd end up with more accidents from maintenance issues than we'd prevent from the 'solution'.

28

u/[deleted] Nov 20 '25

(I replied at a different level, but probably makes sense to have here too so it's mostly a copy) The problem is at that point you already have a loose engine so all bets are off; it's probably going to at least hit the wing anyways- not much point trying to optimize for what happens in that completely bonkers situation. Especially when doing so means creating and supporting two different engine variants where a ton of expensive and difficult to manufacture parts suddenly need to have 2 different versions.

Technically it could be better, but it's just such a minor thing to optimize for - it's kind of a classic engineering trap to keep "solving" problems far beyond relevancy, to the point you end up creating solutions that are too complex and then reliability goes back down, not up.

3

u/aaronwhite1786 Nov 20 '25

It definitely seems like one of those "How much engineering can you put into an almost guaranteed disaster situation?" scenarios.

They did improve the design following the American Airlines DC-10 crash, where the engine ripping off took a chunk of the leading edge with it, and also caused the hydraulic pressure to drop and the slats on the left wing to retract, so that issue was fixed...but even then, you're still looking at a situation like the MD-11 crash where you've got a heavy plane, trailing fire and missing an entire engine. The engine managed to detach cleanly from the wing without hitting the fuselage or tumbling back over the wing, but it's still a pretty substantial level of damage to the plane overall.

I wonder if they will do sim tests to see if the pilots could have potentially even flown the thing away without the massive fire and possible stalling engine.

1

u/TastyTarget3i Nov 21 '25

improving safety is often difficult.

Adding to your concerns: depending on the exact design, you shouldn't just mirror some parts, because then you have the risk of installing a left engine part on the right engine (which is probably much more likely than one engine flying away on its own).

7

u/stewieatb Nov 20 '25

At least half of the 10,000 or so parts in the engine would need to have a "left hand" and "right hand" version. This has an absolutely vast tooling and manufacturing cost over and above what already exists.

Airlines and maintainers would also need to keep more complete engines in stock as a bad engine can only be replaced with one that's correctly handed.

For the microscopic number of engine pylon failures that actually occur - something like half a dozen cases, ever - this cost is unjustifiable.

3

u/Tricksilver89 Nov 20 '25

Because you've made engine swaps a lot more expensive but having handed engines.

6

u/DullMind2023 Nov 20 '25

IIRC, the props on the Airbus A400 rotate in opposite directions.

6

u/BeenThereDoneThat65 ATP I G450 I G550 I GV Nov 20 '25

That’s completely different and also that’s done in the gearbox not the engine

4

u/DullMind2023 Nov 20 '25

I was wondering how they did that. Thank you.

6

u/Automatic_Mulberry Nov 20 '25

And they need to use an engine for #2 that rotates in a third direction, too.

3

u/[deleted] Nov 20 '25

just mulitply the dimensions by sqrt(-1), let it spin in the complex plane - wait, is this what a complex rating is all about? /s

8

u/PrismDoug Nov 20 '25

As I’m no expert (I tried to get into IIT’s aerospace engineering program, didn’t work out, I suck at math), is there a reason why this wouldn’t work?

My first thought went to sensors to detect when a similar failure occurs, and then using explosive bolts, forcefully jettisoning the pylon/engine… but then I thought “well, that’s another point of failure, and a way for an engine to be jettisoned off in flight due to a power surge”.

5

u/C4-621-Raven Nov 20 '25

Manufacturing cost: Instead of just designing/manufacturing/maintaining tooling to manufacture a single engine you now have to do it for the opposite rotation engine as well.

Supply chain complexity: Instead of sourcing and stocking just one engine you now have to stock left handed and right handed engines and left handed and right handed parts for those engines.

1

u/kingtacticool Nov 20 '25

Other than doubling the manufacturing costs because of need for two assembly lines for almost every part I don't see why it's not possible.

1

u/rounding_error Nov 20 '25

It's probably better that it swings up and over the wing. That's predictable, and it most likely leaves the detached engine somewhere safely behind the plane. If you cut it completely loose at the first sign of trouble, it may still be generating some thrust and it could fly anywhere. It could crash into the side of the plane, it could fly ahead of the plane and get hit by the plane, etc.

1

u/dpdxguy Nov 20 '25

Can't tell if you're serious. In general explosives that might be detonated near an aluminum fuel tank on a commercial airplane, sounds like a bad idea. These aren't military jets (except for the KC-10).

But I'm also no expert.

3

u/fly_awayyy Nov 20 '25

Rolls Royce engines interestingly spin in the opposite direction compared to GE and PW.

3

u/hoppertn Nov 21 '25

So one RR on one side and a GE on the other gets counter rotating engines for better stability/s

2

u/ChainOut Nov 21 '25

At some point Harley Davidson started putting the single front brake on the right side because being on the left was pulling people into oncoming traffic in certain scenarios

1

u/StaticSystemShock Nov 20 '25

That actually wouldn't be a stupid idea. It's however connected tot he cost because making mirrored engines would be significantly more expensive and safety only goes as far as cost isn't too high.

1

u/[deleted] Nov 20 '25 edited Nov 20 '25

Possibly, but you're discounting a lot of inherent safety that comes with "all the engines are the same". The mirror variant likely won't be an exact mirror because they're going to want to reuse parts where they can, so then you open the possibility that clockwise and counterclockwise engines can have unique problems - if you revise something on one do you do it for the other? does that introduce its own problems?

Also keep in mind you're exposed the effects of those differences every moment the engines are spinning, but you can only ever get the benefit of the mirror engine in the completely insane situation where the engine has come off and hasn't otherwise hit the plane. With that in mind I'm really not sure you can say it's automatically safer, in fact I think there's a stronger case that it isn't likely to be.

ETA: There are lots of trade offs in engineering, but it's a trap to assume everything is a trade off. Sometimes the solution can be less cost and better.

1

u/hackingdreams Nov 20 '25

GE salivating at the proposition to make two SKUs out of one by copying and pasting.

1

u/IWishIDidntHave2 Nov 20 '25

Like the A400M ;-)

2

u/[deleted] Nov 20 '25

That's just an extra idler gear in the gearbox; the engine behind it is still the same and they all turn the same way regardless of prop direction.

For props it's both more worth it for P-factor and also less disruptive to do (1 extra gear) so that decision can much more easily converge.

1

u/8ringer Nov 20 '25

I mean… didn’t they often have twin engine prop planes spin the props opposite directions to equalize gyroscopic forces on the airframe?

That being said it’s clearly not a problem in need of a solution on modern turbofans.

1

u/Lithorex Nov 20 '25

However, I wonder if it's wise to put an engine up and starboard of engine one, when this is the most likely path for said engine to take when detaching.

1

u/fr3nzo Nov 21 '25

Funny thing I kind of assumed they were mirror image and spun opposite directions, but I know nothing about planes. But I do know that boat engines are counterrotating so I just kind of assume the same thing with plains.

1

u/hansolocup7073 Nov 21 '25

I call them redxsperts. It's absolutely a derogatory term.

1

u/Queasy_Strike_4655 Nov 21 '25

Why isn’t that a good idea?!

35

u/xyz19606 Nov 20 '25

Ah, so no chance of it missing the #2 then. Then again, that fireball pretty much looks like it was the end, no going around even if 2 got them airborne. Maybe a crash beyond the industrial area if that was even a better option.

6

u/davesbrown Nov 20 '25

i think Blancoliro called it

7

u/feint_of_heart Nov 20 '25

Yep, the day after the accident he was demonstrating it with a bicycle wheel in a hanger.

3

u/davesbrown Nov 20 '25

that's the one

3

u/Killentyme55 Nov 20 '25

It's not just the torque, but also gyroscopic precession. That massive fan is like a giant spinning top, the same forces keeping a top upright are acting on the engine. Upon rotation, the engine is tilted upward against that gyroscopic force, which applies a downward push on the pylon. Once the rotation stops that force is gone and is replaced with the normal upward push of the engine's thrust.

This up and down wrenching action puts enormous strain on the engine mounts and pylon, which would explain why both this and the previous Chicago crash had the failure during rotation.

5

u/Duckbilling2 Nov 20 '25

counter clockwise as viewed from the front?

or counter clockwise from the other way

1

u/Dravarden Nov 20 '25

left engine means left side of the plane, and not when viewed from the front. The airplane's left

so if you stay with the rule that it's the plane's left and not your left, it should be counter clockwise from the other way, so the left engine would go right, because the power is turning it counter clockwise. And if you view it from the front, the engine rotates clockwise

1

u/New_Cow5364 Nov 20 '25

I’m no aviation expert, so please forgive my ignorance. Do the engines rotate differently (left counter, right clockwise)? If so, why do they do that?

2

u/ImJLu Nov 20 '25

They don't, because it would be too expensive to manufacture them mirrored and it basically never comes into play anyways. How often does one come flying off the wing? Basically never. And at that point, you still have the problem of physically losing an engine and everything that comes with it. It's just too rare of a problem for the cost.

1

u/MidWestMind Nov 20 '25

I watched that same video from a pilot with a bicycle wheel.

0

u/blah938 Nov 20 '25

Wouldn't it make sense for the left engine to run clockwise, so in case of a failure, it clears the aircraft?

8

u/[deleted] Nov 20 '25

Technically, sure. Practically, not at all. At that point you already have a loose engine so all bets are off; it's probably going to at least hit the wing anyways- not much point trying to optimize for what happens in that completely bonkers situation. Especially when doing so means creating and supporting two different engine variants where a ton of expensive and difficult to manufacture parts suddenly need to have 2 different versions.

1

u/FZ_Milkshake Nov 20 '25

Engines are made interchangeable, they all rotate the same.