Black Boxes on Septemer 11th 2001

the_monkey

Hi,
What is the general consensus on what happened to the black boxes on 9-11 ?

Pulverised beyond use ?

Sorry to ask here, but web searches is giving me conspiracy theory crap ...

Jack1985

Pulverised beyond use we were told, but It's hard to overlook the fact firefighters reported finding them, before FBI officials took them away - and trust me conspiracy theories usually fly over my head, but when you look at accidents such as SilkAir 185 which rammed into the ground plus 500kts and its FDR/CVR were recovered and working or the AF447 FDR/CVR being found at the bottom of the ocean after 2 years and still being in working order it's hard to see why the boxes belonging to 3 of the 4 were pulverized, but to counteract all that the G force could have been a lot larger in each case.

nd001

I think they put it down to the massive temperature endured by the boxes from the fireballs produced. Tte planes would have been full of fuel as we all know. I don't think they are designed to withstand massive heat for prolonged periods

ProfessorPlum

Given that there was enough heat to melt the towers and cause them to collapse, I'd say the recordes were fairly well melted too.

nd001

Yes the towers were unfortunately inaccessible by fire fighters on the high rise floors and as a result the fires burnt on as proffesor plum said causing massive structural weakness to the main reinforced steel joints and eventually collapse of the buildings. It takes a massive amount of heat to melt steel so I imagine the boxes would have went after a relatively short amount of time. I could be wrong but I think one of the buildings was on fire close to an hour before collapse

knucklehead6

Were the black boxes (or at least the CVR) recovered from flight 93? I thought they were.

nd001

As far as I keep the flight 93 boxes were recovered in working conditon it was the flights in new York and Washington they had trouble with

mickdw

The fire must have destroyed all the CCTV systems monitoring the pentagon and surrounding areas too.

roundymac

mickdw wrote: »

The fire must have destroyed all the CCTV systems monitoring the pentagon and surrounding areas too.

No it did'nt, there is a clip of the plane hitting the Pentagon, not a great clip, building is there in one clip next clip is the explosion and fire.

martinsvi

nd001 wrote: »

I think they put it down to the massive temperature endured by the boxes from the fireballs produced. Tte planes would have been full of fuel as we all know. I don't think they are designed to withstand massive heat for prolonged periods

FDR's and CVR's are certified to withstand a temperature of 1000°C for 30 minutes, jet fuel (jet A) burns at the temperature of about 300°C (if not injected with an airflow as it happens in engine. If a constant pressurized flow of air is delivered, it can reach close to 1000°C)

I don't think it was the fire that destroyed them

mickdw

roundymac wrote: »

No it did'nt, there is a clip of the plane hitting the Pentagon, not a great clip, building is there in one clip next clip is the explosion and fire.

Well we know the building was hit, we saw plenty clips of the damage. I have not seen any video of the plane approaching or hitting it though which is just astonishing.

n32

mickdw wrote: »

Well we know the building was hit, we saw plenty clips of the damage. I have not seen any video of the plane approaching or hitting it though which is just astonishing.

There is a cctv video of the plane impacting the building

mickdw

If that is the time lapse one, I couldnt see a plane on it

Paulw

mickdw wrote: »

Well we know the building was hit, we saw plenty clips of the damage. I have not seen any video of the plane approaching or hitting it though which is just astonishing.

Yeah, because so many cctv systems look up at the sky, rather than at ground level.