Scientists Discover New Stealth Feature on H.L. Hunley

Navy Newsstand ^ | 6/21/2005 | Raegan Quinn

[Excuse_My_Bellicosity]

CHARLESTON, S.C. (NNS) -- Conservators of the Civil War submarine H. L. Hunley, working with the Naval Historical Center (NHC), discovered a previously unknown stealth feature called a deadlight while removing the concretion on one of the 10 glass ports, June 15.

The deadlight, which served like skylights that run along the top of the submarine, served as both a stealth and safety feature on Hunley, by stopping light from getting out and water from getting into the submarine.

"The Hunley truly is a technological marvel. Every aspect of the submarine's design is thought out to maximize her ability as a stealth and functional weapon," said Sen. Glenn McConnell, chairman of the Hunley Commission. "She is literally 50 years ahead of her time."

The skylight is covered by a hinged iron plate, or deadlight. A pin could be removed from one hinge, allowing the iron plate to drop down and let light in to the otherwise dark vessel. To cover the skylight, a crew member would push the iron plate up and re-insert the pin. When the deadlight was closed, it would block light from exiting the submarine through the skylight, increasing the Hunley's ability to approach her target unnoticed.

The deadlights also served as an important safety feature of the sub's construction. During combat, if the glass of the skylight was broken, it could cause a dangerous flow of water into the submarine. Scientists think the two hinges holding the iron plate in place may have been fitted with rubber gaskets, which would make the skylight watertight when the iron plate was closed. If the glass on the skylight was damaged, the crew could lock the iron plates in place and stop water from overtaking the sub.

Hunley scientists discovered the deadlight was in the shut position and the skylight remained covered.

"Every discovery is a clue that we will ultimately use to solve the mystery of the Hunley's disappearance. In the crew's last moments, they chose to leave this skylight closed, perhaps because they believed they would be returning home and wanted to remain undetected," McConnell said. "This is another piece of the puzzle that will lead us to the ultimate answer."

Scientists will continue work on de-concreting the remaining deadlights as they prepare the submarine for its conservation treatment.

On the evening of Feb. 17, 1864, H.L. Hunley became the world's first successful combat submarine by sinking USS Housatonic. After signaling to shore that the mission had been accomplished, the submarine and her crew of eight vanished.

Lost at sea for more than a century, Hunley was located in 1995 by author Clive Cussler's National Underwater and Marine Agency (NUMA). The hand-crank-propelled vessel was raised in 2000 and delivered to the Warren Lasch Conservation Center, where an international team of scientists under the Naval Historical Center are at work conserving the vessel and piecing together clues to solve the mystery of her disappearance.

For related news, visit the Naval Historical Center Navy NewsStand page at www.news.navy.mil/local/navhist/.

[Excuse_My_Bellicosity]

This story was posted a few days ago. The Navy story here has updated info.

030221-O-0000O-002 Naval Historical Center, Navy Yard, Washington D.C. (Feb. 21, 2003) -- Scientists at the Warren Lash Conservation Center examine a Civil War-era wallet found during excavation of the Confederate submarine H.L. Hunley. The archeologists stated that the wallet was in remarkably good condition. Hunley was recovered from the ocean floor in 2000 and has been under an excavation and conservation program, which has been led by the Naval Historical Center team for three years. U.S. Navy photo courtesy Naval Historical Center. (RELEASED)

[cherokee1]

Sounds like a porthole to me----there's a whole bunch of good reasons that subs don't have ém. But God bless the old timers for trying. Altho this isn't yet identified as the reason the Hunley went down it would have been sooner or later. ---another reason we say the Navy ship design book is written , page by page, in blood.

[Van Jenerette]

...Deo Vindice!

[Bogey78O]

Wonder if the glass broke and the seal didn't function.

[dixie sass]

Well hello there you two. Was just thinking about y'all and the family! How are you doing?

[TXnMA]

As in the earlier article, this report is full of it. The "deadlights"were the windows, themselves. They have been known at least since (?Alexander's?) 19th-century drawing of the Hunley.

The new revelation is that the topside deadlights had shutters that could be pinned open or shut.

As another FReeper said, (paraphrased) "Why is it when the press writes about something about which I have first-hand knowledge -- they always get it wrong?"

What's worse, this dumb@SS is writing for the Naval Historical Center, where all of the info on the Hunley is available. What ever happened to doing background research before going out to work a story?

[TXnMA]

Ping to another article on the Hunley...

[Redbob]

And rubber seals?
Before Charles Goodyear's process for vulcanizing rubber was invented?

[Doctor Stochastic]

Good design is a result of experience.
Experierce is a result of bad designs.

[Van Jenerette]

Was just thinking about y'all and the family! How are you doing?

Hi Dixie! We're all fine. The children are keeping us busy and me working all the time between the University and the College teaching our students the 'rightness' of our Constitution and the Political system.

I still hit them up with "Bibles & Gunpowder and the American Revolution" and have a newer lecture..."Darwin meets Jesus in America's Public Schools: Why The Atheist want our Children to learn Natural Selection but quietly Need them to behave like Good Tolerant Christians.

I'm having fun and the Liberals are going nuts...life couldn't be better for Katherine and I; she's the CEO/Executive Director of the Myrtle Beach Area Hospitality Association now, so you know who wears the pants in our family.

Hope you are well! Take care!

[lOKKI]

I'm not sure why we're supposed to be amazed or even interested by this poor piece of reporting.

It's just another example of an idiot's surprise that anyone who lived in the past had any intelligence at all.

James Thurber put it best:

"Why are we so amazed than an ancient Egyptian could draw a duck that looks like a duck?"

[razorback-bert]

Nothing about the screen door?

[dixie sass]

I'm so glad to here that everything is going well with y'all. It does sound like the two of you are busy!

You should post that new lecture here at FR, especially in light of some of the articles that I have been reading. I just pinged y'all to one and have another in mind.

Hope to see y'all sometime in the future.

[Rodney King]

Nothing about the screen door?

I thought that was on the Polish submarine.

[TalonDJ]

There was still rubber before then. Just not as good. Gaskets don't have to flex much and undersea the temperature range is not as much of an issue.

[TalonDJ]

I disagree that it was a bad feature. This ship had to use lamps under water. I.E. fire and some smoke. When running near or on the surface these windows would have allowed them to run without burning things inside. Modern battle subs don't have port holes but bathyscapes do and they go deeper. On a battle sub they are pointless since there are electric lights and not a usable amount of light at periscope depth.

[Ditto]

Scientists Discover New Stealth Feature on H.L. Hunley

Well duh! It stayed hidden on the bottom for 140 years. Of course it was "steathy." ;~))

[TXnMA]

The deadlight shutters are an interesting discovery but, as far as I can tell, were mostly unnecessary. AFAIK, the only light inside the Hunley (to be blocked-off by the shutters) was a single candle that Dixon had in the forward conning tower.

That candle was supposedly to enable Dixon to see the compass. (Don't ask me how they got a magnetic compass to work inside that iron can shield...)

It was supposedly Dixon's candle that provided the light (through the forward-facing deadlight in the forward hatch tower) at which the Housatonic's Capt Pickering fired his shotgun.

The crew knew that flames consumed oxygen (a precious commodity inside the Hunley), so I seriously doubt there would have been additional candles back in the hull where the shutters were installed. (During an experiment on how long they could stay down, records tell that they remained under for an hour after the depleted air extinguished Dixon's candle...)

[The_Victor]

And rubber seals? Before Charles Goodyear's process for vulcanizing rubber was invented?

Just what I was thinking too. The seals would have had to be cork or leather.