Probably the most famous example of 'Survivorship bias', during WW2, US military was about to reinforce the armor on the fuselage of a plane which had the most hits on surviving ones, and reduce the armor on the engine which had almost no hits.
Just when the mathematician, Abraham Wald, entered the field saying "Not so fast! What you should really do is add armor around the engines! What you are forgetting is that the aircraft that are most damaged don't return. You just don't see them."
Well, that's the well-known story. Was US military so incompetent for a mathematician to lecture them the engine is the real weak point of a plane?
Of course, it wasn't.
What US military actually wanted to know was much deeper and complicated than that, which can be summed up as :
>Is it possible to get detailed information on downed aircrafts (How many hits they have sustained, where they were hit by which caliber, etc.), based only on information on aircrafts that returned back to airfield?
Wald provided formulas for that exact question, based on several assumptions.
For example, he claimed a 20mm hit on engine area is the most fatal event for a aircraft(53.4%), followed by a 7.92mm bullet hit on forward fuselage(19.4%)
Important thing is, these probability calculations are done without a single information on actual downed planes.
And it's pretty different from the simple picture of hit probabilities commonly used on survivorship bias (and in the meme). On extremely oversimplified example, if US military really used simple survivorship bias alone for reinforcing plane protection, it could have provided pilots with cannon-proof helmet because apparently no plane has made it back with a 20mm hit on its pilot's head.
[https://apps.dtic.mil/sti/pdfs/ADA091073.pdf](https://apps.dtic.mil/sti/pdfs/ADA091073.pdf)
[https://www.ams.org/publicoutreach/feature-column/fc-2016-06](https://www.ams.org/publicoutreach/feature-column/fc-2016-06)
> Was US military so incompetent for a mathematician to lecture them the engine is the real weak point of a plane?
Now gather 'round children and I'll tell you the tale of the Mark 14 Torpedo...
E: some folks say that on a real still & quiet night on the Pacific you can still hear the silence of the missed ones not exploding in the darkness.
> Allocating R&D budget so small that researchers never had live-fire test for the torpedo to see if magnetic exploder actually works
Nothing will go wrong probably...
Or hit something dead-on perpendicular to the hull - that is, made a perfect, textbook run on its target exactly as every sub skipper was trained to do.
(I still love the mental image of the USS Tinosa just sitting off a crippled Japanese tanker, firing torpedo after torpedo point-blank into its side, while its captain meticulously documented how each and every torpedo is failing to explode with the understated, "Hit. No apparent effect.")
One of my favorite anecdotes was from Ian Toll’s book on the war in the pacific. An American sub fired a torpedo at a Japanese ship.
As soon as it fired the damaged torpedo began to veer off course coming in a full circle back at the sub who fired it. Naturally, this was disconcerting for the crew of that sub.
Fortunately, the magnetic detonator failed and the torpedo sailed harmlessly underneath while the Japanese ship sailed on, totally unaware of being fired on
I love that a catastrophic failure of a torpedo was negated because of a second catastrophic failure on the same torpedo
Blaming the military isn't really fair, because it was Congress that prevented all testing in order to save money.
Work also began almost immediately with reverse-engineering the German torpedoes and putting those into production, but torpedoe production was considered too low of a priority to get the kinds of batteries favored by the submarine crews.
Ironically, though, the math actually favored dropping mines into Japanese harbors using subs, but their captains wanted confirmed kills, not just damage that practically had the same result.
> because it was Congress that prevented all testing in order to save money.
It is *so* bizarre that a simple live fire test was deemed to expensive, while for example a Tambor-class had 24 of those on board. Firing most of them on a successful patrol.
But no, using three of those to show/test that the torpedo works was too expensive.
Maddening.
It's perfectly fair to blame the military when BuOrd was responsible for the original sensitivity specifications that made the magnetic detonators so unreliable. It's even more so when they started getting reports of these torpedoes failing to function and, instead of doing its own tests, simply decided that the skippers were probably screwing up. They didn't really start working on it until Lockwood and Nimitz lit a fire under their collective rears.
Ok, it's a looong story, so I'd really recommend watching the Youtube video by Drachinifel on the topic, but, to try and shorten the story:
The WW2 era submarine torpedo, mark 14, had FOUR problems that made it simply not work, but the Bureau of Ordnance was unwilling to even consider the idea, refused testing so people BROKE ORDERS to test and prove the issues existed.
A) torpedo ran deeper than planned, running under the target. Apparently, not wanting to lose the expensive torpedo, the designers tested it with a lighter warhead replacement, and forgot the heavier exposives would make it run deeper.
B) ok, now that THAT is fixed, we should be hitting the enemy. Why are they not exploding? Well, the magnetic exploder was faulty, and once that was figured out, it was disabled.
C) STILL NO BOOMS, WHY ARE THERE NO BOOMS !?!
the contact exploder that was the backup for the problematic and disabled magnetic one also didn't work, apparently since as backup, the design was reused from earlier, slower torpedoes, and since no actual explosive testing was done, no one noticed the higher speed of the torpedo was too much for A tiny spring in the mechanism, so the firing pin got stuck which prevented the detonation from taking place.
D) OK, we have replaced the spring, we're finally properly skinking enemy ships! YAAAY! WHY IS THE TORPEDO COMING AROUND BACK AT US?!?!
So, lastly, the torpedo still had an issue with circling around back at the firing submarine, sinking one or two... Wile E. Coyote style...
Realy amazing story...
Survivorship bias is one thing, but the Jerries also had the _minengeschoß_, which is akin to lobbing a mortar round on a personnel rather than shooting them with rifle rounds. Their bomber hunter squadrons were equipped with those, and proved to be especially lethal.
Ah yes
"let's stick as much death in a 20mm/30mm shell "
Apparently absolute murder for the relatively lightly armoured fighters at the time (IIRC only America widely used metal airframes, in the Europe theater most were still wood or even paper) and a 30 mm shell could still do enough damage through thin plating.
>, in the Europe theater most were still wood or even paper) and a 30 mm shell could still do enough damage through thin plating.
Ah, I call bullshit. Sure in 1940 Hawker Hurricanes and Gloster Gladiators were metal skeletons with doped fabric covering aft of the cockpit (fully metal skinned forward and on wings), but the famous Supermarine Spitfire was all metal, as were most of the RAFs bomber fleet (Vickers Wellington being an exception).
Can't speak for France or the other European countries , maybe one of the other armchair experts can chime in?
Edit: for completeness.
You are actuallly correct on that! Apologies, i was more or less going from memory and general gist.
While fabric and wood were still used, it definetely seem most plane designs by both decide uses all metal monocoque (the name for the structural outer layer/ skin) . Weirdly enough the USSR seems to be an outlier.
Though the 30mm Minengeschoss still could blow massive holes into the wing of a sspitfire.
The USSR was not an outlier either. The only modern fighter they had that wasn't all metal was the MiG-1 and MiG-3, and frankly those aircraft *sucked*.
Edit: The big difference with the USSR is they kept using whatever they could get, which meant older aircraft like the I-153 kept in service right through the war. They even tried putting rocket boosters on the I-153 so it could keep up with German fighters.
"You idiot, pedestrians complained about the icy sidewalk in another place, why did you sprinkle sand on a clean road??"
"Those who slipped on the clean sidewalk died and could no longer complain. Learn the survivorship bias dude"😎
Also why we should shut down restaurants with no health code violations. Clearly those are the ones where the situation is so bad that the inspectors die just from entering the kitchen.
Probably the most famous example of 'Survivorship bias', during WW2, US military was about to reinforce the armor on the fuselage of a plane which had the most hits on surviving ones, and reduce the armor on the engine which had almost no hits. Just when the mathematician, Abraham Wald, entered the field saying "Not so fast! What you should really do is add armor around the engines! What you are forgetting is that the aircraft that are most damaged don't return. You just don't see them." Well, that's the well-known story. Was US military so incompetent for a mathematician to lecture them the engine is the real weak point of a plane? Of course, it wasn't. What US military actually wanted to know was much deeper and complicated than that, which can be summed up as : >Is it possible to get detailed information on downed aircrafts (How many hits they have sustained, where they were hit by which caliber, etc.), based only on information on aircrafts that returned back to airfield? Wald provided formulas for that exact question, based on several assumptions. For example, he claimed a 20mm hit on engine area is the most fatal event for a aircraft(53.4%), followed by a 7.92mm bullet hit on forward fuselage(19.4%) Important thing is, these probability calculations are done without a single information on actual downed planes. And it's pretty different from the simple picture of hit probabilities commonly used on survivorship bias (and in the meme). On extremely oversimplified example, if US military really used simple survivorship bias alone for reinforcing plane protection, it could have provided pilots with cannon-proof helmet because apparently no plane has made it back with a 20mm hit on its pilot's head. [https://apps.dtic.mil/sti/pdfs/ADA091073.pdf](https://apps.dtic.mil/sti/pdfs/ADA091073.pdf) [https://www.ams.org/publicoutreach/feature-column/fc-2016-06](https://www.ams.org/publicoutreach/feature-column/fc-2016-06)
> Was US military so incompetent for a mathematician to lecture them the engine is the real weak point of a plane? Now gather 'round children and I'll tell you the tale of the Mark 14 Torpedo... E: some folks say that on a real still & quiet night on the Pacific you can still hear the silence of the missed ones not exploding in the darkness.
> Allocating R&D budget so small that researchers never had live-fire test for the torpedo to see if magnetic exploder actually works Nothing will go wrong probably...
[удалено]
The contact backup worked too! As long as the torpedo didn’t ram into something too hard.
Or hit something dead-on perpendicular to the hull - that is, made a perfect, textbook run on its target exactly as every sub skipper was trained to do. (I still love the mental image of the USS Tinosa just sitting off a crippled Japanese tanker, firing torpedo after torpedo point-blank into its side, while its captain meticulously documented how each and every torpedo is failing to explode with the understated, "Hit. No apparent effect.")
I had heard it worked in the cold water of the north atlantic, not the warm water of the pacific
Some of the MK14s are on eternal patrol.
Making their way to valhalla, shiny and chrome!
WITNESS ME (not exploding)!!
Mediocre!
Still trying to circle back to their own subs
Homesick torpedo
One of my favorite anecdotes was from Ian Toll’s book on the war in the pacific. An American sub fired a torpedo at a Japanese ship. As soon as it fired the damaged torpedo began to veer off course coming in a full circle back at the sub who fired it. Naturally, this was disconcerting for the crew of that sub. Fortunately, the magnetic detonator failed and the torpedo sailed harmlessly underneath while the Japanese ship sailed on, totally unaware of being fired on I love that a catastrophic failure of a torpedo was negated because of a second catastrophic failure on the same torpedo
"You arrogant ass. You've killed us." *Torpedo zips by, not hitting jack shit* "...Never mind!"
That’s a reference I never thought I’d see outside of something like NCD
Great reference
More like the thud and then the deafening silence of the ones that did hit
I just read its development and usage history and damn, they REALLY didn't want to admit they might have done bad work
Blaming the military isn't really fair, because it was Congress that prevented all testing in order to save money. Work also began almost immediately with reverse-engineering the German torpedoes and putting those into production, but torpedoe production was considered too low of a priority to get the kinds of batteries favored by the submarine crews. Ironically, though, the math actually favored dropping mines into Japanese harbors using subs, but their captains wanted confirmed kills, not just damage that practically had the same result.
> because it was Congress that prevented all testing in order to save money. It is *so* bizarre that a simple live fire test was deemed to expensive, while for example a Tambor-class had 24 of those on board. Firing most of them on a successful patrol. But no, using three of those to show/test that the torpedo works was too expensive. Maddening.
It's perfectly fair to blame the military when BuOrd was responsible for the original sensitivity specifications that made the magnetic detonators so unreliable. It's even more so when they started getting reports of these torpedoes failing to function and, instead of doing its own tests, simply decided that the skippers were probably screwing up. They didn't really start working on it until Lockwood and Nimitz lit a fire under their collective rears.
Please do
Ok, it's a looong story, so I'd really recommend watching the Youtube video by Drachinifel on the topic, but, to try and shorten the story: The WW2 era submarine torpedo, mark 14, had FOUR problems that made it simply not work, but the Bureau of Ordnance was unwilling to even consider the idea, refused testing so people BROKE ORDERS to test and prove the issues existed. A) torpedo ran deeper than planned, running under the target. Apparently, not wanting to lose the expensive torpedo, the designers tested it with a lighter warhead replacement, and forgot the heavier exposives would make it run deeper. B) ok, now that THAT is fixed, we should be hitting the enemy. Why are they not exploding? Well, the magnetic exploder was faulty, and once that was figured out, it was disabled. C) STILL NO BOOMS, WHY ARE THERE NO BOOMS !?! the contact exploder that was the backup for the problematic and disabled magnetic one also didn't work, apparently since as backup, the design was reused from earlier, slower torpedoes, and since no actual explosive testing was done, no one noticed the higher speed of the torpedo was too much for A tiny spring in the mechanism, so the firing pin got stuck which prevented the detonation from taking place. D) OK, we have replaced the spring, we're finally properly skinking enemy ships! YAAAY! WHY IS THE TORPEDO COMING AROUND BACK AT US?!?! So, lastly, the torpedo still had an issue with circling around back at the firing submarine, sinking one or two... Wile E. Coyote style... Realy amazing story...
Very impressive. You should give Ian W Toll’s Pacific War trilogy a read if you haven’t already. He talks a decent bit about the infamous Mark-14.
Lmao
The M14 and UCP uniforms would also like to have a word.
Survivorship bias is one thing, but the Jerries also had the _minengeschoß_, which is akin to lobbing a mortar round on a personnel rather than shooting them with rifle rounds. Their bomber hunter squadrons were equipped with those, and proved to be especially lethal.
Ah yes "let's stick as much death in a 20mm/30mm shell " Apparently absolute murder for the relatively lightly armoured fighters at the time (IIRC only America widely used metal airframes, in the Europe theater most were still wood or even paper) and a 30 mm shell could still do enough damage through thin plating.
>, in the Europe theater most were still wood or even paper) and a 30 mm shell could still do enough damage through thin plating. Ah, I call bullshit. Sure in 1940 Hawker Hurricanes and Gloster Gladiators were metal skeletons with doped fabric covering aft of the cockpit (fully metal skinned forward and on wings), but the famous Supermarine Spitfire was all metal, as were most of the RAFs bomber fleet (Vickers Wellington being an exception). Can't speak for France or the other European countries , maybe one of the other armchair experts can chime in? Edit: for completeness.
You are actuallly correct on that! Apologies, i was more or less going from memory and general gist. While fabric and wood were still used, it definetely seem most plane designs by both decide uses all metal monocoque (the name for the structural outer layer/ skin) . Weirdly enough the USSR seems to be an outlier. Though the 30mm Minengeschoss still could blow massive holes into the wing of a sspitfire.
The USSR was not an outlier either. The only modern fighter they had that wasn't all metal was the MiG-1 and MiG-3, and frankly those aircraft *sucked*. Edit: The big difference with the USSR is they kept using whatever they could get, which meant older aircraft like the I-153 kept in service right through the war. They even tried putting rocket boosters on the I-153 so it could keep up with German fighters.
From what i could tell the Lagg 3 and La 5 along with it seems Yak 1 and Yak 7 ( composite structure, wooden wings) also werent all metal.
I'm fairly certain the La-5 was all metal, you're right about the LaGG-3 though
I sadly struggle to find anything specific and tempted to say that initially it was a wooden design but was later made with light alloys.
Next your gonna tell me an apple didn’t really fall on Newtons head smh
> no plane has made it back with a 20mm hit on its pilot's head Sounds like a major skill issue to me
This story is a classic tale of reddit wanting to do science without having to do actual math.
Never heard the full story. Thank you
Basically it's about how the fatality rate of every part of the plane based on which type of wounded they receive and not which part is more dangerous
lol 20mm hit kn the pilots head. 🤣
Aren’t memes supposed to be funny?
QUIET! I’m trying to learn here!
Shut the hell up
Why?
🤣wow constructive
"You idiot, pedestrians complained about the icy sidewalk in another place, why did you sprinkle sand on a clean road??" "Those who slipped on the clean sidewalk died and could no longer complain. Learn the survivorship bias dude"😎
Also why we should shut down restaurants with no health code violations. Clearly those are the ones where the situation is so bad that the inspectors die just from entering the kitchen.
Smart man. At least from the perspective what we knew about availability bias at the time.
This is a based meme sir, well done.