Author Topic: Launch Complex 39 Sound Suppression  (Read 1107 times)

Offline agusaf

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Launch Complex 39 Sound Suppression
« on: 05/17/2017 02:24 PM »
I've been looking over historical photographs of Launch Complex-39 from the Apollo era vs. now and have noticed the large water towers were added post-Apollo for the Shuttle program.  Where did NASA store the water needed for sound suppression on the Saturn V Mobile Launchers?
« Last Edit: 05/17/2017 04:53 PM by agusaf »

Offline capcomespace

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Re: Launch Complex 39 Sound Suppression
« Reply #1 on: 05/17/2017 03:56 PM »
I belive water come from industrial aera by pipe under the ground.
Didier Capdevila
www.capcomespace.net

Offline Michel Van

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Re: Launch Complex 39 Sound Suppression
« Reply #2 on: 05/24/2017 03:44 AM »
So far i know was problem the extrem noise of two SRB of shuttle during liftoff
that NASA install the Water Tower to flood the Mobile launcher Platform with 
1,100,000-litre (300,000 US gal) water during 6 seconds at liftoff

The Saturn V was "less noisy" with it five F-1 engines
and needed far less water as the Shuttle, because it was used as thermal protection of Mobile launcher Platform
not for noise reduction

Offline Brusion

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Re: Launch Complex 39 Sound Suppression
« Reply #3 on: 05/24/2017 03:50 AM »
Also, for the SRB's specifically, they added those layers of rubber bladders filled with water that burst when the blast hit them.

Offline Michel Van

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Re: Launch Complex 39 Sound Suppression
« Reply #4 on: 05/24/2017 07:53 AM »
Depending the sources of NASA:
The Saturn V generated a sound level of 91 decibels from a distance of 9384 m.
The Space Shuttle generated a sound of 90 decibels at distance of 9384 m.

more here
http://www.airliners.net/forum/viewtopic.php?t=1015753

Decibels is a logarithmic unit used to express the ratio of two values of a physical quantity.
more on that here https://en.wikipedia.org/wiki/Decibel

Offline IRobot

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Re: Launch Complex 39 Sound Suppression
« Reply #5 on: 05/24/2017 08:10 AM »
Depending the sources of NASA:
The Saturn V generated a sound level of 91 decibels from a distance of 9384 m.
The Space Shuttle generated a sound of 90 decibels at distance of 9384 m.
That does not tell the whole story. Although the SPL are similar, maybe the frequency distribution is quite different.

A lower frequency sound is more dangerous for the whole body, as it can shake internal organs. A high frequency sound is easily stopped by the skin or clothes, but can cause deafness.
Regarding infrastructure, low frequency vibration is of course much more damaging.

Also it is hard to extrapolate from Saturn V, as low frequency interference and cancelation depends on distance between engines.
« Last Edit: 05/24/2017 08:46 AM by IRobot »

Offline Blanik

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Re: Launch Complex 39 Sound Suppression
« Reply #6 on: 05/24/2017 11:04 AM »
From the top of my head without cross-checking books (e.g. Jenkins' wonderful Shuttle book) first: I do not recall what effect the noise level of the burning SRBs and SSMEs had, but the SRB ignition shock wave reflected off pad structures and impinged on the Orbiter with undesireable effects, e.g. deflecting aerosurfaces. That's why the water-filled bags suspended in the SRB troughs were introduced.

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