I am trying to wrap my head around the decision of Taiho's damage control officer to essentially turn his ship into a 900ft FAE bomb.
Was there no other means available to him in addressing the gas fume issue?
Was flame retardant foam not a thing in the IJN circa 1944?
Taiho's damage control
Taiho's damage control
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Richard Anderson
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Re: Taiho's damage control
Chemical fire retardants date to the early 1900's but were difficult to use and transport since they required mixing two or more chemicals at the time of use. Protein-based foams were developed around 1933 but had a limited shelf life and had to be stored at critical temperatures. I doubt either would have been used on any naval vessels of the time. It wasn't until the 1960's that synthetic fire retardants became available.Kingfish wrote: ↑16 Feb 2023, 03:05I am trying to wrap my head around the decision of Taiho's damage control officer to essentially turn his ship into a 900ft FAE bomb.
Was there no other means available to him in addressing the gas fume issue?
Was flame retardant foam not a thing in the IJN circa 1944?
Richard C. Anderson Jr.
American Thunder: U.S. Army Tank Design, Development, and Doctrine in World War II
Cracking Hitler's Atlantic Wall
Hitler's Last Gamble
Artillery Hell
American Thunder: U.S. Army Tank Design, Development, and Doctrine in World War II
Cracking Hitler's Atlantic Wall
Hitler's Last Gamble
Artillery Hell
Re: Taiho's damage control
Foam firefighting systems were around pre-WW2 and were part of the detailed specification of the Essex class carriers issued on 5 Feb 1941. I’m away from my library at present but ISTR they were present on US carriers immediately pre-war or were about to be fitted.
Pre-war Japanese carrier fire fighting systems were based around the use of “fire-protection bulkheads” and “fire-protection curtains” and a CO2 system fed from bottles. The idea was that the CO2 would sink to just above deck levels, thereby suppressing any hangar fires.
Midway proved existing arrangements were inadequate for a variety of reasons, so in late 1942 the Japanese set about developing a foam fire fighting system. After trials of various chemical mixes, a system using a soap solution was adopted. This would be mixed with air and water and sprayed across the hangars to extinguish or smother fires. This was installed on the Taiho and retrofitted to surviving earlier ships. CO2 systems were retained in Taiho for the lower hangar and aviation fuel tank groups and surrounding compartments.
But note these foam systems are all about fire suppression not to the prevention of fuel vapours escaping.
Taiho was also provided with hangar ventilation improved from earlier ships, including fans that could renew the air therein 8-12 times per hour.
The effect of the torpedo hit was to increase her draught forward by 1.5m. It also ruptured the forward aviation fuel tanks, directly under the forward lift. That resulted in a water/petrol/oil mix in the forward lift well but no fire and was no doubt exacerbated by the movement of the ship stirring it all up. Attempts were made by damage control personnel using gas masks to plug the holes in the petrol tanks but despite this the concentration of petrol vapour increased. Attempts were also made to pump the dangerous mix overboard with only limited success. The after lift was lowered (the forward one was damaged and jammed between fight and hangar decks and had been planked over to allow air operations to continue) until air operations needed to restart.
The bottom line was that her hangar ventilation systems were overwhelmed by the volume of vapours involved. The mistake by her damage control officer was to order the general ship ventilation system to be turned on to try to reduce the vapour concentration. Maybe if the forward lift well had been kept open / reopened a greater throughflow of air might have been achieved to clear the vapours.
Controlling petrol vapour was a constant problem with carrier design for all nations. The RN had the highest WW2 standards with petrol tanks placed in water filled compartments. The price was reduced petrol capacity. The US and Japanese navies opted for petrol tanks surrounded by CO2 filled compartments. For the USN the retrofitting of its carriers with CO2 systems was accelerated after the loss of Lexington but was already part of the Essex design. The problem with this was that battle damage allowed the CO2 to leak out, which was part of the problem with the loss of the Wasp CV-7 and with Taiho.
The Japanese later filled the previously CO2 filled compartments with concrete in an effort to increase their protection by elimination the opportunity for vapours to escape.
The USN chose to redesign the petrol tanks in later Essex class ships into a saddle tank arrangement, which as the petrol was used, allowed the remaining fuel to be almost totally surrounded by water (in other words moving towards the RN position). Enterprise was refitted with such an arrangement in 1943. The later Essex class also moved the forward petrol tanks further aft where the ship was wider. The problem again was that these later measures reduced to petrol capacity of the ships.
For those in the US for petrol read avgas.
Pre-war Japanese carrier fire fighting systems were based around the use of “fire-protection bulkheads” and “fire-protection curtains” and a CO2 system fed from bottles. The idea was that the CO2 would sink to just above deck levels, thereby suppressing any hangar fires.
Midway proved existing arrangements were inadequate for a variety of reasons, so in late 1942 the Japanese set about developing a foam fire fighting system. After trials of various chemical mixes, a system using a soap solution was adopted. This would be mixed with air and water and sprayed across the hangars to extinguish or smother fires. This was installed on the Taiho and retrofitted to surviving earlier ships. CO2 systems were retained in Taiho for the lower hangar and aviation fuel tank groups and surrounding compartments.
But note these foam systems are all about fire suppression not to the prevention of fuel vapours escaping.
Taiho was also provided with hangar ventilation improved from earlier ships, including fans that could renew the air therein 8-12 times per hour.
The effect of the torpedo hit was to increase her draught forward by 1.5m. It also ruptured the forward aviation fuel tanks, directly under the forward lift. That resulted in a water/petrol/oil mix in the forward lift well but no fire and was no doubt exacerbated by the movement of the ship stirring it all up. Attempts were made by damage control personnel using gas masks to plug the holes in the petrol tanks but despite this the concentration of petrol vapour increased. Attempts were also made to pump the dangerous mix overboard with only limited success. The after lift was lowered (the forward one was damaged and jammed between fight and hangar decks and had been planked over to allow air operations to continue) until air operations needed to restart.
The bottom line was that her hangar ventilation systems were overwhelmed by the volume of vapours involved. The mistake by her damage control officer was to order the general ship ventilation system to be turned on to try to reduce the vapour concentration. Maybe if the forward lift well had been kept open / reopened a greater throughflow of air might have been achieved to clear the vapours.
Controlling petrol vapour was a constant problem with carrier design for all nations. The RN had the highest WW2 standards with petrol tanks placed in water filled compartments. The price was reduced petrol capacity. The US and Japanese navies opted for petrol tanks surrounded by CO2 filled compartments. For the USN the retrofitting of its carriers with CO2 systems was accelerated after the loss of Lexington but was already part of the Essex design. The problem with this was that battle damage allowed the CO2 to leak out, which was part of the problem with the loss of the Wasp CV-7 and with Taiho.
The Japanese later filled the previously CO2 filled compartments with concrete in an effort to increase their protection by elimination the opportunity for vapours to escape.
The USN chose to redesign the petrol tanks in later Essex class ships into a saddle tank arrangement, which as the petrol was used, allowed the remaining fuel to be almost totally surrounded by water (in other words moving towards the RN position). Enterprise was refitted with such an arrangement in 1943. The later Essex class also moved the forward petrol tanks further aft where the ship was wider. The problem again was that these later measures reduced to petrol capacity of the ships.
For those in the US for petrol read avgas.