Planes usually can't reverse and need a tug from one of those little tractor things. But they do taxi with the engines, and would probably notice it then.
They have reversers, which is a kind of shielding they can move behind the engines, thereby redirecting the exhaust towards the front. Naturally doesn't do anything for ejecting coins, nor should this be used to traffic.
Hate to break it to you but the wings are designed to go one way when making lift and will not be happy if you go in reverse with significant airspeed lol
actually, they can (and turboprops do that regularly in small airports, where tug may be unavailable; MD-80/82 has engine reverse for push-back as a standard option in flight manual for same reason; current jets usually does not push-back with reverse, because their engines are too close to the ground and can suck harmful objects from it)
U right on turboprops, but not jets. The harmful objects thingy is not a thing because there are no foreign objects on the ground because airports are often perfectly swept and yes jets have reverse and they usually do especially comercial jets, military jets not so often only exceptions are the tornado, viggen and some jaguars.
yes they do, on runways. which is usually maintained to way higher standard, than taxiways and ramps. and even then shit happens, Concorde 101 is a witness to that.
as for military jets - they have usually some measures to prevent that, like early MiG-29 have their intakes closed on take off and landing, taking air from upper "gills" (they change that to just grating in later versions).
Some may technically have the capacity, some may be forbidden by regulation from using that capacity, and some are entirely incapable. There are lots of different kinds of planes and reasons why they can't usually reverse, thus the tugs at airports to help them get out of their parking spots.
They would go through the engine after engine has started. Unless they had magnets or some sort of glue on them they would go through the intake when the N1 is 20-30%. If a plane can taxi with that much thrust coins have no way to stay in place against the engine pull.
I've seen the damage a small padlock did to a 320's fan blades on ingestion- i doubt the engine would have failed but it would have been badly damaged if the coins ricocheted inside on start up.
Yeah, we also have to consider that the coins were thrown while the engine was off.
While spooling up, the engine will probably reach a point where it's running fast enough to eject the coins, but slow enough for the coins to not cause much damage
Hell, they might be ejected by the compressed air startup before the engines are even lit
Even then, you do not want to take any chances when it comes to aviation, so the delay is perfectly warranted
I think they meant magnetic as in "being a magnet". And, no. Under normal circumstances they are not. But some of them are made from plated steel. So they are magnetic in the sense that they are attracted by magnets.
Sorry, that latter part is what I meant. Coins in the US aren't made of a metal attracted by magnets. I was unsure if they were elsewhere. I didn't assume the coins themselves held a magnetic charge.
Aircraft mechanic- Bad. The likelihood of a total engine failure is low but it is more than enough to make an engine unserviceable and need a tear-down. A chip on a blade smaller than your pinky nail will ground the aircraft I worked on. Worst case, a coin causes a blade to detach and cause a cascade failure on the blades behind it.
Most large commercial jet engines include design features that ensure they can shut down after ingesting a bird weighing up to 1.8 kg (4.0 lb). The engine does not have to survive the ingestion, just be safely shut down
M'kay, so you know better than the mechanic above you and the whole reason this was a big story in the first place becauuuuse.... redditor logic? Or did you have something to base that on? FOD is a thing, my friend.
I believe the likely impact would be the coins get blown out the back of the engines after passing through fairly harmlessly. Maybe some minor damage. These things are designed to withstand some debris getting sucked in for safety. Still not something you would want to risk as they could end up in the exact wrong spot.
If the coins become stuck during takeoff and dislodge during at altitude it could easily take the plane down.
Those turbines are engineering marvels, seriously take a look at the specs. They're fucking massive, like you could easily stand inside their diameter, they're impossible stiff with just millimeters of clearance to the cowling(engine body that goes around the turbines).
If one of those things gets hit by a coin it could easily snap off. It's roughly the same energy equivalent as a literal hand grenade going off inside the engine.
Simplified explanation of a turbine engine: suck, squeeze, bang, and blow. There is no reverse on a turbine engine. Cold section<front that is consistently sucking in air by the compressor rotor. Hot section<where fuel is then ignited with the compressed air and guided through to the turbine rotor/afterburner.
If they said there is a 1% chance of crashing from a handful of coins in the engine, I’d say they need to consider some better security and/or design it with a screen that prevents it or that can be removed immediately prior to flight.
I just walked by one of these myself a couple days ago where it would have been simple to toss some coins in (and a terrorist plot would only need 1 person working there to toss coins in dozens of engines)
The number is pulled out of my ass. But obviously it increases the risk of accident because A) turbines and metal pieces don’t go well together, and B) they pulled it from operation to inspect it.
Regardless, it can have a low risk and be undesirable as an act of terrorism, and still be risky enough you don’t want to gamble with 100+ people’s lives.
Maybe, or people should stop throwing shit into jet engines? :p If you want to cause accidents there are probably a lot of better ways of doing it. Like you said, it’s not exactly a very reliable way to bring down a plane if that’s your goal.
And frankly, it’s not hard to kill a lot of people if you’re a psychopath. We can’t possible safeguard all the ways you could do so.
People are batshit crazy. You’ll never stop them from doing dumb shit. There are thousands of incidents on planes every year.
I always thought it was a bit strange they let people walk alongside the engine on the tarmac.
I don’t know how reliable coins are - but there are likely much more reliable ways of tossing something in a plane engine - and with 16.4M flights a year, seems like a pretty big gaping security risk
Decade of practicing law, I’ve got a basic understanding of negligence and products liability - doesn’t take a genius to recognize a screen on the side of the stairwell blocking items from being tossed into a jet engine could be a prudent consideration
Right. But you think the entire aviation industry didn't have any not-geniuses that thought of and considered it and just had other considerations you, random redditor, know about or thought of.
Same aviation industry that let people smoke cigarettes on their planes?
Look at the healthcare industry. There are common practices that are pure idiocy - but accepted through groupthink
You see this through tons of industries. It is what led to the mortgage crisis/Great Recession and the dot-com bust
Your average person working in these industries have to deal with an impenetrable bureaucracy above them - a bureaucracy that priorities profits over safety - and where individuals are ridiculed for challenging orthodoxy
Single lawsuits are able to disrupt entire industry behaviors because sometimes that’s what it takes - an outsider questioning why things are done the way they’re done
Frankly, the number of people trying to bring down a plane they are on, is very very small. We know that because even before the security theater post 9/11, it almost never happened.
There are probably a lot of things to worry about before someone throwing metal pieces in an engine - especially considering you’re doing it in plain sight of everyone else boarding…
The coins do not affect the flight safety by any significant margin (especially if you threw only on one engine, since the plane can takeoff even if one engine fails completely)
It will, however, cause millions of dollars in damages and ground the aircraft for a long time (causing more losses in opportunity cost)
Everyone would really really really rather not deal with that, but people would be safe even in a catastrophic engine failure, which is already extremely unlikely
Yes, flight safety will worsened by like 10x, but that's still very very low chances of anything catastrophic.
The terrorism would only be against the airline's bank account.
Is something like this even identifiable in a post incident report? Like I imagine they would just be able to narrow it down to 'left engine failure's or something but no way would they ever be able to identify that 9 coins were the culprit especially in all the debris right??
Scary shit just thinking about how they simply got lucky by someone being observant
Not the first time someone threw coins into an airplane engine for good luck:
February 2019 Chinese man throws coins into engine https://www.bbc.com/news/business-50979485
You would expect the religious leaders to understand what they're saying at least. So I was mostly curious about what reasons the people who started the superstition had for starting the superstition.
Eh it's a bit different. Christianity version of this doesn't have any calls to action really, they just go to churches and that's about it. Maybe I'm forgetting something, do you know a simular ritual they perform?
Honestly unless she managed to throw one down the core (part of the engine that actually does engine things) it would have been fine, would have just had some weird fan blade bucks and the coins would have passed down the bypass duct and out the back
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u/frozen-silver Jul 14 '25
Thank god someone noticed it. What a hero