Corrective measures after 1971
Many measures were taken and implemented from 1968 and especially from 1970 by the navy after the submarine accidents.
Families
The wives, alone and without news during the long patrols of their husbands, were able to be helped and assisted for many steps, in particular administrative.
Human aspects
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Training
As we read in the "Confidentiel Défense" file of the Minerve, there is a lot to do on this side.
There is no simulator yet and many sailors train, on a practical level, alongside their companions, once on board.
For example, Lieutenant Merlo testified before the commission of inquiry about the broadcasting of submarine incidents.
"These broadcasts are always made orally. [I personally believe] that it would be good if there were some sort of periodic broadcast of incidents involving the lives of submarines."
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The procedures
Certain practices could put the crew in danger at critical moments, such as the complete and simultaneous change of position at each watch change; this could lead to dramatic consequences if they were concomitant with a potentially serious situation.
The accidents involving the Minerve and the Eurydice occurred during a change of watch.
During this period, which could last up to 30 minutes, the men would all leave their posts simultaneously to make way for those replacing them. If an incident occurred at that precise moment, which was the case with the Minerve, the temporary absence of personnel at their posts could have dramatic consequences.
Not only was there no one left on duty, but if the submarine took on a significant attitude (tilt), the men could no longer maintain their positions.
For instructions to staff
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shift staff can no longer move at the same time
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the watch stations have been equipped with handrails.
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Damage response instructions have been changed.
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The shift changes were staggered in time H-15 minutes; H, and H+15.
For equipment
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Bar damage
The frequency of breakage of the tiller hoses was, before the Minerva, already considered critical. They were replaced by copper "hunting horn" pipes.
The rudders (which steer the submarine in depth for diving) are corrected and balanced. Until then, if the rudder was out of balance, it naturally rallied to the dangerous position (+30°), aggravating the point of the submarine.
Text of a 1999 conference, internal to the Navy on the accidents of the Minerve and the Eurydice
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Snorkel
After the three water entry events in the snorkel of Minerve, Eurydice and Flora (assumed for the first 2 and certain for Flora) two additional modifications to those cited have been made.
1. Installation of a grid on the water inlet lantern of the air tube to avoid the entry of foreign bodies..
On the photo of the Minerve snorkeling opposite in 1961, we can clearly see that the air inlet passage is very wide, and can possibly allow a foreign body to pass under the head valve of the tube. air and thus hinder the closure of said valve, hence the possibility of water ingress.
2. Installation of a pneumatic press to assist in closing the cupola.
The dome is a "Plug" or "Valve" that closes the air intake pipe of the snorkel at the entrance to the thick hull of the submarine.
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Before this addition of a pneumatic closing press, the cupola, dropped by the master of the central during "Alert", fell from its own weight, then was locked manually. Or , after study, tests and lab trials (following the Flora event), we observed the dome could not fall under its own weight in the event of strong attitude (positive or negative), and strong water entry to the air tube. A very strong movement of water flow in a spiral (siphon) which can form and keep the dome open under the effect of the forces generated by the water, tending on the contrary to go up it.
For the "Dive safety"culture
In the 70s documents containing reviews and analyzes of incidents will be published.
Known as the “diving safety information bulletin” or BISP, these thirty-page booklets were four in number.
Their importance was such that the visa of all officers and central masters, attesting to the consultation, was required annuallyon a butterfly pasted on the second cover of each of the 4 booklets. They were part of the documents presented to the Admiral in general inspection identically, for example, orders of the commander. The authority then had a visa.
It even happened that this one questioned a young officer in 5th: “the incident of ... in 19.., what do you know about it?” It was better to know.
Article by Jean Lle Tallec for the magazine "La Baille" of January 2020 on the measures following the accidents of the Daphné submarines
Confidence eventually returned, because after the Flore in 1971, there were no more major accidents on this type of submarine.
At the end of the 1980s, there were even some Daphne-class submarine commanders who declared that they had only discovered the tragedies of the Minerve and the Eurydice later.