Wash Down Countermeasure

Whilst idly flicking through stuff about the USS Ronald Regan I noticed a few images described as the carrier trying out a "Wash Down Countermeasure"....what is this countermeasure meant to counter and how? (Pic hopefully below so you can see)

Almost definately it's to clean up after an NBC (Nuclear Biological Chemical) attack. That's the only thing that washing the deck would do is to get any radiation, or leftovers from an attack of that type.

According to a comic i read its against nbc attacks.

This is a text describing the picture from the first post.

Counter-Measure Wash Down
At sea aboard Precommissioning Unit (PCU) Ronald Reagan (CVN 76) May 7, 2003 -- The Navy's newest Nimitz-class aircraft carrier tests its counter-measure wash down systems (CMWDS) during scheduled builder sea trials off the coast of Virginia. CMWDS includes a series of sprinklers in vital areas throughout the ship to help contain the spread of fire or chemical, biological, radiological (CBR) attacks. U.S. Navy photo by Photographer’s Mate 2nd Class James Thierry. (RELEASED)

Here´s another test photo from the USS Nimitz:



[edit on 4/7/2005 by Lonestar24]

I was wondering who would be the first to make that joke. heh.

CBR=NBC. Fire is a HUGE thing to worry about on a carrier. Just look at the Forrestal off of Vietnam, and the Enterprise off of Hawaii. They came pretty close to losing Forrestal due to the fact that all their firefighters were killed and the rest of the crew didn't have proper training, so they were using foam and water on the same sitres. The foam would hit, then the water would wash it away. I had heard about them designing a system like this, but I didn't know that they had put it on the Regan or had gone beyond the design phase.

[edit on 4-7-2005 by Zaphod58]

i doubt about the capblites of clear the fire.
and in case NBC attack deck could be cleaned but what about aircraft, euipment and men power on the deck.

Originally posted by mirza2003
i doubt about the capblites of clear the fire.
and in case NBC attack deck could be cleaned but what about aircraft, euipment and men power on the deck.

Read a few post up and the article.

The ship was on sea trails when the pic was taken....this is probably one of the many test they have to undergo before it can be commissioned or something like that.

EDIT: Bad info

[edit on 4/7/2005 by SportyMB]

Regan has been in commision for awhile now. She's made at least two deployments I think. I know she's made one, but she's been here twice. That pic was TAKEN during sea trials. That would be a HUGE benefit during a deck fire. As far as an NBC attack, it would also decontaminate the planes on deck, as long as the deck, and any other equipment. Any personnel on deck would probably already be dead depending on what was used against them. It would be a huge benefit for the ship.

Here's a little on the Regan.
* Dec 8, 1994 Contract awarded to Newport News Shipbuilding
* Feb 12, 1998 Keel laid
* Oct 1, 2000 Precommissioning Unit established
* March 4, 2001 Christened by Mrs. Nancy Reagan
* May 5, 2003 First underway
* July 12, 2003 Commissioned
* July 23, 2004 Arrived at homeport in San Diego, CA

I was told by a sailor once on one of Austraia's frigates that washdowns are primarily used to remove radioactive fallout following a nuclear explosion.

I know there are some real experts on this board, and I aint one, lol, so please feel free to correct me if I'm wrong.

www.tpub.com...

Here's a little bit that might be helpful. It's used intermittently under MOPP Level 3 conditions, when a biological attack is possible, and continuously under MOPP Level 4 conditions when a biological attack is imminent. MOPP= Mission Oriented Protective Posture

Here's another thing that you might find interesting. Not so much for the countermeasures washdown, as just for the interesting CBR information.

www.navygirl.com...

All I have to say is that fist picture looks amazing it looks as if there is a misty water cloud on the deck nice picture. By the way doesn't water only intensify fuel or grease fires?

Originally posted by WestPoint23
All I have to say is that fist picture looks amazing it looks as if there is a misty water cloud on the deck nice picture. By the way doesn't water only intensify fuel or grease fires?

Well, there IS a misty water cloud on the deck...that's the whole purpose.

The water, in case of fire, is to keep the deck and ship overall cool and wet. Oil and fuel will be washed away and overboard.

All USN ships that I am aware of have a water wash down system. The ship I served on (laid down in 1965) had one. It's primary use was for NBC defense, and it could be used for class 'A' fires. It was specifically prohibited to use it for class B' fires, and for obvious reasons wouldn't be used for class 'C' fires. The system could be used to attempt to limit the spread of class 'D' fires, but would have little effect on the fire itself.

It was tested at regular intervals, but it's use was kept as limited as possible. Think about it, spraying salt water all over a metal ship....

yes they are for NBC protection. Although there are constant rumours that the type 45's have a modified system on board the prodces a cloud of mist around the ship helping to hide it.

Originally posted by JamesinOz
I was told by a sailor once on one of Austraia's frigates that washdowns are primarily used to remove radioactive fallout following a nuclear explosion.

I know there are some real experts on this board, and I aint one, lol, so please feel free to correct me if I'm wrong.

I'm no expert but did serve on both CV-66 and CVN-68. What I remember from firefighting/damage control is that the water washdown could be used with Class A or Class B fires. The Bravo fires would be fought by activating AFFF agent which would spray through the washdown system and float on top of water, smothering any fuel fires.
In NBC warefare, it would be activated just after a nuke detonation to create a barrier to stop radioactive spray from nuke column or base surge. A nuke did not have to hit the ship to damage or sink it so we practiced against close detonations. Obviously the direct-hit posed greater damage control issues, right! I don't know how realistic that was but I didn't make up the scenarios. Chem and Bio weps are obvious. Wash it down!
Salutations

The CMWD (Counter Measure Washdown) system is used to prevent NBC material from adhering to the hull of a warship. You activate the system before an attack and leave it running throughout the attack. Once the attack is complete you can send out decontamination teams to clean up any "spots" that remain.

It is not used as any kind of fire fighting device. There are hoses staked all throughout the ship to fight the fires. The CMWD system could possibly be used to cool a topside surface that is being heated by a fire. But that would seriously tax your firemain system.

Hope this helps.

Coolhand,
I think that you are right. No AFFF through washdown. Sorry, my bad. 25 years will take a toll on memory! CV-66 got the ultimate water washdown-6000ft of Atlantic Ocean! What a bummer. Rest in Peace, America, you were a fine ship.