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USS Bonhomme Richard LHD-6, is on fire in San Diego right now.

Truckedup said:
I'm thinking that jet fuel injected into high pressure turbines burns a lot hotter than fuel burning on decks or in somewhat confined spaces...The big clouds of smoke means less than complete combustion...Yes?
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Not a turbine guy: Jet turbines use metallurgy and manipulation of the exhaust flow to protect the nozzles from melting. It's constantly blowing exhaust gases out of the nozzle, and the cooler gases are layered near the engine housing. This also pulls air around the outside of the turbine across the housing, which cools it. The sheer between the very fast exhaust gases, and the slower outside gases, is the 'rip' that jet engines make at high power, and this is also what cools the exhaust housing, and this is also why the housing is usually bare on military jet engines. They use the same principal in civilian turbines, but they're contained in a housing to reduce noise an increase safety.

F-35, bare exhaust

main-qimg-3c2346ed83a008e9f19fd8b9a0c52d6b.webp


787 GEnx engine, with serrated nacelle to reduce the shear between turbine exhaust and ambient air, quiets it down:

787engine.jpg



If you hold an F-35 exhaust on the flight deck of any ship, regardless of coating, it is eventually going to weaken that steel and burn through it. 2000 C, steel melts at 1510 C.
 
Truckedup said:
I'm thinking that jet fuel injected into high pressure turbines burns a lot hotter than fuel burning on decks or in somewhat confined spaces...The big clouds of smoke means less than complete combustion...Yes?
Click to expand...

Yeah but the temps are handled by engineering.

I'll play along with the 'play dumb and let evernoob write stuff' game everyone is playing...

John C. Stennis was ordered in 1988 and she's the first HSLA-100 major unit. Prior to this carriers, Tico cruisers, and submarines were built out of HY-100, and smaller vessels out of HY-80. The HY steel alloys are expected military grade, 80,000 psi tensile.

The problem is that they require pre- and post-treatment after welding or bending. HSLA is high-strength, low-alloy, with the number again being Xk-psi tensile.

HSLAs are supposed to be both cheaper, and easier to deal with in terms of modification and on-board repairs. There should also be more ductility and tolerance against spalling and shredding.

So if an HY-alloy ship is damaged at sea and then repaired, the repairs aren't going to be as robust as with an HSLA vessel. Obviously a shipyard with proper facilities is going to be able to post-heat and test repairs better than a bunch of traumatized Hull Techs under pressure to make the vessel operational.

This really does go straight back to the USS Yorktown being damaged at Coral Sea, then requiring 3 weeks of repairs then getting underway in 2 days instead, to take part in Midway, where she was eventually sunk. However, her role at Midway, which is not only the most stunning upset in the Pacific War but one of the most stunning military reversals in History, really does have an influence on Naval doctrine and construction.

AFAIK the the Bonhomme Richard, laid down in 1992, is an HSLA-100 ship. The LHDs and LHAs are 'cheaper' versions of aircraft carriers, the CVNs, SSNs, and SSBNs get all of the Park Avenue treatment, and I can't confirm LHD-6 is HSLA-100. But I do believe she is, and if so, it's the first real test of HSLA-100 in a fire situation.

There will be people wanting to rebuild the vessel, and the Navy is going to be very eager to see how she tolerated damage, regardless of whether it's rebuilt. This event is going to have a ripple effect on the Navy for a long time.
 
evernoob said:
787 GEnx engine, with serrated nacelle to reduce the shear between turbine exhaust and ambient air, quiets it down:

787engine.jpg
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Close.... The 787 (and most transport jets) uses high-bypass turbofans. The serrated edge on the nacelle smooths the air transition from the bypass fan air (outer) to the turbine air (center), not the ambient air.
 
Thunderer said:
Close.... The 787 (and most transport jets) uses high-bypass turbofans. The serrated edge on the nacelle smooths the air transition from the bypass fan air (outer) to the turbine air (center), not the ambient air.
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There's not an important distinction for the discussion.
 
Turns out my mom's cousin's son was on it when the fire happened. Not sure how close he was to the actual fire, but did have to get treated for smoke inhalation. He's fine though.
 
Paragon said:
Correct information should always should be the most important distinction in any discussion. Except when you attempt to hide your ignorance in verbosity
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You know why my troll effect on you is so effective? Because I'm not actually trolling. You're a try-hard. Try harder, try-hard.

KarlVP said:
Fire has been declared to be out. Press conference happening now.
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All we've got now is after-action reports, investigations, and memos to look at.

Lot of unanswered questions. #1 thing I see is a lack of co-ordination between the civilian fire agencies and the Navy during a shipyard fire. You'd think that would have been sewn up after USS Miami. Ships enter a kind of quasi-civilian authority during RAs and that was clearly displayed in the first 24 hours of fire-fighting. On the scanner, by how the two DDGs were moved, how long it took for civilian tugs to show up. RADM Sobeck and Chief Stowell made a lot of statements about 'unified command'. To me it looked like disunity. 10 or 12 hours for private tugs to show up?

Lot of holes need to be filled right now.
 
evernoob said:
You know why my troll effect on you is so effective? Because I'm not actually trolling. You're a try-hard. Try harder, try-hard.



All we've got now is after-action reports, investigations, and memos to look at.

Lot of unanswered questions. #1 thing I see is a lack of co-ordination between the civilian fire agencies and the Navy during a shipyard fire. You'd think that would have been sewn up after USS Miami. Ships enter a kind of quasi-civilian authority during RAs and that was clearly displayed in the first 24 hours of fire-fighting. On the scanner, by how the two DDGs were moved, how long it took for civilian tugs to show up. RADM Sobeck and Chief Stowell made a lot of statements about 'unified command'. To me it looked like disunity. 10 or 12 hours for private tugs to show up?

Lot of holes need to be filled right now.
Click to expand...
Nope
 
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