A13 O2 Tank Rupture Was Not An Explosion

Recent quotes he

"After the explosion on the A13 SM..."

"When power and heat were off after the exploson..."


Years ago I had a discussion with someone who was on the A13
investigation board. He explained to me that the tank did not
explode. It could more accurately be described as the cap getting
blown off followed by O2 streaming away, the force of which tore away
the SM panel and such. The tank rupture was just not violent enough
to qualify as an explosion. Even in Ron Howard's movie, Lovell is
shown looking outside as the O2 sprays off. Had the tank actually
exploded, its contents would have been gone in one shot.


(Along with Apollo 13, it is also popular to hear -51L, -107 and
sometimes even A204 being referred to as an "explosion". Let's not
mistake colloquialism for accurate descriptions of the failure modes.)


~ CT

"Stuf4" wrote in message
om...
|
| It could more accurately be described as the cap getting
| blown off followed by O2 streaming away, the force of which tore away
| the SM panel and such.

Yes, "explosion" is the wrong word. However, gaseous O2 loss continued
after the first tank failure because oxygen from the undamaged tank was
leaking away through the damaged plumbing. There was no tank isolation
valve at that time.

--
|
The universe is not required to conform | Jay Windley
to the expectations of the ignorant. | webmaster @ clavius.org

In article ,
says...

"Stuf4" wrote in message
om...
|
| It could more accurately be described as the cap getting
| blown off followed by O2 streaming away, the force of which tore away
| the SM panel and such.

Yes, "explosion" is the wrong word. However, gaseous O2 loss continued
after the first tank failure because oxygen from the undamaged tank was
leaking away through the damaged plumbing. There was no tank isolation
valve at that time.

Though, IIRC, the images taken of the damaged SM (and the eyewitness
accounts by the crew) testify that the O2 tank that "exploded" was *not*
in the tank shelf in the bay.

--

Do not meddle in the affairs of dragons, for | Doug Van Dorn
thou art crunchy and taste good with ketchup |

On 1 Sep 2003 22:52:24 -0700, (Stuf4)
wrote:

Years ago I had a discussion with someone who was on the A13
investigation board. He explained to me that the tank did not
explode.

I stand corrected.

It could more accurately be described as the cap getting
blown off followed by O2 streaming away, the force of which tore away
the SM panel and such. The tank rupture was just not violent enough
to qualify as an explosion. Even in Ron Howard's movie, Lovell is
shown looking outside as the O2 sprays off. Had the tank actually
exploded, its contents would have been gone in one shot.

I thought that the oxygen on one tank immediately went to zero, and
the other gradually went to zero. I would guess that the venting was
from the later.

On Tue, 02 Sep 2003 23:56:55 -0400, Jan Philips
wrote:

On 1 Sep 2003 22:52:24 -0700, (Stuf4)
wrote:

Years ago I had a discussion with someone who was on the A13
investigation board. He explained to me that the tank did not
explode.

I stand corrected.

....Do *not* stand corrected wherever this particular troll is
concerned. Again, do a google on "~CT" or "Stuff4" and see just what
sort of bull**** games he plays in his posts. Best bet is to killfile
him and be done with him for all time.

OM

--

"No ******* ever won a war by dying for | http://www.io.com/~o_m
his country. He won it by making the other | Sergeant-At-Arms
poor dumb ******* die for his country." | Human O-Ring Society

- General George S. Patton, Jr

From Jud:

It could more accurately be described as the cap getting
blown off followed by O2 streaming away, the force of which tore away
the SM panel and such. The tank rupture was just not violent enough
to qualify as an explosion. Even in Ron Howard's movie, Lovell is
shown looking outside as the O2 sprays off. Had the tank actually
exploded, its contents would have been gone in one shot.

I thought that the oxygen on one tank immediately went to zero, and
the other gradually went to zero. I would guess that the venting was
from the later.

Never hurts to go straight to the official word: "REPORT OF APOLLO 13
REVIEW BOARD" - http://tinyurl.com/m2nm
(http://spacelink.nasa.gov/NASA.Proje...ard.Report.txt)

"It is now clear that oxygen tank no. 2 or its associated tubing lost
pressure
integrity because of combustion within the tank, and that effects of
oxygen escaping from the tank caused the removal of the panel covering
bay
4 and a relatively slow leak in oxygen tank no. 1 or its lines or
valves."

[Compare/contrast "lost pressure integrity" versus "exploded". Toward
the end of the report, the terminology they used is "pressure pulse".]

"After the relatively slow propagation process ... took
place, there was a relatively abrupt loss of oxygen tank no. 2 integ-
rity. About 69 seconds after the pressure began to rise, it reached
the
peak recorded, 1008 psia, the pressure at which the cryogenic oxygen
tank
relief valve is designed to be fully open. Pressure began a decrease
for 8
seconds, dropping to 996 psia before readings were lost."

[NASA knows that pressure vessels are potential bombs. This one was
designed to relieve extreme pressure in a non-catastrophic way:
through designed pressure release mechanisms.]

"27. Findings

a. The pressure relief valve was designed to be fully open at
about 1000 psi.

b. Oxygen tank no. 2 telemetry showed a pressure drop from
1008 psia at 55:54:45 to 996 psia at 55:54:53, at which time
telemetry data were lost.

Determination

This drop resulted from the normal operation of the pressure
relief valve as verified in subsequent tests."


*


There's lots more excellent info in that report. I've distilled the
sequence of events for anyone interested:

________

55:52-:31 Master caution and warning triggered by low hydrogen
pressure in tank no. 1. Alarm is turned off after
4 seconds.

55:52:58 Ground requests tank stir.

55:53:06 Crew acknowledges tank stir.

....

55:53:20 Oxygen tank no. 2 fans turned on.

....

55:53:22.757 1.2-volt decrease in ac bus 2 voltage.

55:53:22.772 11.1-amp rise in fuel cell 3 current for one
sample.

55:53:36 Oxygen tank no. 2 pressure begins rise lasting
for 24 seconds.

....

55:53:41.192 Stabilization control system electrical disturbance
indicates a power transient.

55:54:00 Oxygen tank no. 2 pressure rise ends at a pressure
of 953.8 psia.

55:54:15 Oxygen tank no. 2 pressure begins to rise.

55:54:30 Oxygen tank no. 2 quantity drops from full scale
for 2 seconds and then reads 75.3 percent.

55:54:31 Oxygen tank no. 2 temperature begins to rise
rapidly.

55:54:43 Flow rate of oxygen to all three fuel cells begins
to decrease.

55:54:45 Oxygen tank no. 2 pressure reaches maximum value
of 1008.3 psia.

55:54:48 Oxygen tank no. 2 temperature rises 40ø F for one
sample (invalid reading).

55:54:51 Oxygen tank no. 2 quantity Jumps to off-scale high
and then begins to drop until the time of telemetry
loss, indicating failed sensor.

55:54:52 Oxygen tank no. 2 temperature reads -151.3ø F.

55:54:52.703 Oxygen tank no. 2 temperature suddenly goes off
scale low, indicating failed sensor.

55:54:52.763 Last telemetered pressure from oxygen tank no. 2
before telemetry loss is 995.7 psia.

....

55:54:56 Oxygen tank no. 2 pressure reads off-scale low fol-
lowing telemetry recovery, indicating a broken supply
line, a tank pressure below 19 psi, or a failed
sensor.

55:54:56 Oxygen tank no. 1 pressure reads 781.9 psia and
begins to drop steadily.

55:54:57 Oxygen tank no. 2 quantity reads off-scale high
following telemetry recovery indicating failed sensor.

....

55:55:20 Crew reports, "I believe we've had a problem here."

55:55:35 Crew reports, "We've had a main B bus undervolt."

55:55:49 Oxygen tank no. 2 temperature begins steady drop
lasting 59 seconds, probably indicating failed sensor.

55:56:10 Crew reports, "Okay right now, Houston. The voltage
is looking good, and we had a pretty large bang
associated with the caution and warning there. And
as I recall, main B was the one that had had an amp
spike on it once before."

55:56:38 Oxygen tank no. 2 quantity becomes erratic for 69
seconds before assuming an off-scale-low state,
indicating failed sensor.

55:57:04 Crew reports, "That Jolt must have rocked the
sensor on--see now--oxygen quantity 2. It was
oscillating down around 20 to 60 percent. Now
it's full-scale high again."

....

__________


~ CT

It could more accurately be described as the cap getting
blown off followed by O2

Ahh I think pressure relief valves would be a good addition to any tank.
Keeping the pressure just below what would blow or permanetely damage the tank
or systems.

Plus vent them to prevent collateral damage in the event of a problem. The
final vent port could be a burst one so as to defend from a bad or leaking
valve.

Was any of this added to later designs?

If this would of been on apollo 13 the landing would of been scrapped but the
crew would of had much of its oxygen and none of the fears of engine damage.
That with the seperate battery and extra oxygen would of allowed a faster
return and much less drama. Probably no movie.

It could more accurately be described as the cap getting
blown off followed by O2

Ahh I think pressure relief valves would be a good addition to any tank.
Keeping the pressure just below what would blow or permanetely damage the
tank
or systems.

Plus vent them to prevent collateral damage in the event of a problem. The
final vent port could be a burst one so as to defend from a bad or leaking
valve.

Was any of this added to later designs?

If this would of been on apollo 13 the landing would of been scrapped but the
crew would of had much of its oxygen and none of the fears of engine damage.
That with the seperate battery and extra oxygen would of allowed a faster
return and much less drama. Probably no movie.



Forgot to add this isnt high tech, just check any hot water tank for at least
the last 50 years or more. That pressure valve as saved lots of lives

"Hallerb" wrote in message
...

Nothing even vaguely resembling an answer to my question. If he simply
"would of" posted an answer, I "would of" stopped reminding him.
--
If you have had problems with Illinois Student Assistance Commission (ISAC),
please contact shredder at bellsouth dot net. There may be a class-action
lawsuit
in the works.