The story of an elementary error of the command, which threatened a waste of resources and almost cost the lives of many pilots. A story about missing holes and a mystery that means more than the obvious. Hidden meaning? Rather, a typical delusion inherent in human imperfection.
Technical reference
The mass of armor plates in the later modifications of the "Fortresses" reached 900 kg. On lighter vehicles, protection was also used, which was continuously strengthened with the escalation of hostilities.
Aircraft armor was not designed for direct hits from shells. Its task is to cover the vital components of the aircraft from a swarm of debris generated by remote detonation of anti-aircraft ammunition. And also from the fire of small-caliber aircraft cannons and fighter machine guns.
In addition to booking the cockpit, main components and assemblies, other effective measures were used to localize damage and the ability to continue the flight if damage was received. Multi-engine circuit, duplication of vital systems (wiring, control rods), protection of fuel tanks and pressurizing their free volume with nitrogen or engine exhaust gases. Someone went even further, installing a steel "ski" inside the fuselage to rescue the pilot during a hard landing.
The strongest survived in battle. Aircraft protection concepts evolved continuously throughout the war. And the designers were faced with the question - on the basis of the available data, to anticipate and predict the most effective ways to solve the problem.
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Manhattan, 118th Street, Morningside Heights. The location of the Center for Statistical Research for solving military problems. Abbreviated - SRG.
Among the staff of the Center were the best mathematicians of that era: Nobert Wiener, Leonard Savage, the future Nobel laureate M. Friedman.
They counted everything. The most advantageous weapon combinations. Bombing methods. Ammunition sampling schemes (when with the least effort it is possible to check a sufficient number to conclude that the standards of a particular batch of shells are met).
A group of scientists led by Abraham Wald was tasked with analyzing the damage and finding the optimal booking scheme. Which parts of the plane need the most protection?
As a subject of a "hostile country", Wald formally did not have access to classified documents. Colleagues joked that the "special officers" should immediately snatch the reports compiled by him from his hands so that he did not have time to read them.
The working group of statisticians was presented with extensive material on aircraft returning from the mission, whose planes and fuselages looked like Swiss cheese. Based on the results of the damage analysis, diagrams were drawn up, indicating the most vulnerable points.
The greatest number of hits occurred along the wing planes, in the area of the tail defensive installation and on the lower side of the fuselage.
The problem was successfully solved. The command officials saw the possibility of increasing the survivability of aircraft by strengthening protection in the vulnerabilities found.
The only one who expressed doubts was Abraham Wald. He examined the photographs, but did not see traces of hits in the engines and the cockpit. According to the Hungarian mathematician, this could mean the following.
Or the fragments are particularly selective in the choice of targets, they fall everywhere, except for the cockpit and engines.
The second explanation is that planes with a dead crew and a damaged engine, as a rule, did not return from a mission. There was nothing to photograph.
Just like the majority of patients in military hospitals are wounded in the limb. But that doesn't mean the bullets don't hit the head. This is evidence that those injured in the head, as a rule, die on the spot.
Therefore, it is a mistake to draw conclusions only on the basis of returned aircraft.
The ridged planes and fuselage do not need additional protection measures. The presented facts indicate that their strength is sufficient to continue the flight even with extensive damage to the skin and power set.
All available reserves should be spent on protecting critical critical nodes, damage to which will inevitably lead to disaster.
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Why was Abraham Wald able to see something that all Air Force officers with a set of professional knowledge and understanding of the laws of air combat did not see at close range? As noted above, this was due to the imperfection of human thinking. Overgrown with a set of stereotypes, we are no longer able to see the truth in all its simplicity and beauty. The only one who was able to ask the right question and get the right answer was a mathematician, accustomed to looking at things from an analytical point of view.
As for the problem itself with mysteriously disappeared holes, this phenomenon has become known as the “survivor bias”. And it is found not only in war, but in almost any situation.
It is based on the drafting of laws, advice and instructions only on the basis of successful examples. Unsuccessful ones - into the furnace. All advertising is based on this, any diets, lotteries and urban legends. Stories about how dolphins push drowning people to the shore (after all, those who were pushed from the shore could not share their experience). And so on, so on.
There are so many successful people in this hall! (And how many unsuccessful ones.)
The stories about Bill Gates, who dropped out of school and achieved success, serve as an example for the already not very literate and not aspiring to knowledge victims of the exam.
As for the title topic of the article, an elementary, obvious and now simple mistake made by the responsible officials of the Air Force is an indicator of the peculiarities of human thinking. We are all imperfect, nothing can be done about it. And it is good that in that situation there was at least someone who doubted the generally accepted current of view, thought about the facts left unattended and was able to point out an error.
