Mast or Antenna - Antenna or Mast

Post here about equipment carried on ships
User avatar
Little h
Posts: 1727
Joined: Sun Aug 12, 2018 6:53 pm

Mast or Antenna - Antenna or Mast

Unread post by Little h »

Remember this photograph I posted in the WNSF......

Gravely CDR Salamander blogspot.jpg
DDG-107-photo-011 (2).jpg
seaforces.org


.... well here are a couple of articles relating to the event, followed by an update that I have only just found on t'internet.
------------------------------



Remember the USS Gravely? Well, the ship is back in the news
Wednesday, February 16, 2011 at 7:11 by Gareth McGrath

Remember the USS Gravely, which created a bit of a stir when she was commissioned here late last year?

Well, she’s back in the news.

It seems part of the new destroyer’s mast collapsed on Sunday while the Arleigh Burke-class destroyer was on routine patrol off Florida, according to the website Defense News.

Here’s the Navy’s description of what happened:

“While underway conducting routine operations Feb. 13, USS Gravely (DDG 107) experienced structural damage to the mast mounted antenna. No personnel were injured during the incident,” Cmdr. Elissa Smith, a spokesperson for the Second Fleet in Norfolk, said in a Feb. 15 e-mail to Defense News.

“USS Gravely’s crews took immediate action and secured the damaged mast-mounted antenna. The cause and extent of the damage is unknown. The ship safely returned to Mayport, Fla. at approximately 10 a.m. local yesterday and is undergoing assessment. Commander, U.S. Second Fleet and Commander, Naval Surface Force Atlantic are taking prudent actions to ensure safe, efficient and effective repairs to the ship. Naval Sea Systems Command (NAVSEA) is leading the investigation to identify the root cause of the failure.”

Oh, and it was just the Gravely’s luck that a video-production crew from Discovery Channel Canada and Exploration Productions in Toronto was on board the Gravely at the time of the incident, working on an upcoming episode of the Mighty Ships series.

A spokesman for the company declined comment when reached by Defense News.

Cape Fear Watchdogs StarNews On Line

------------------------------
021511dn_mast-snap-315.JPG

Tuesday, 15 February 2011
U.S. Navy Destroyer's Mast Breaks Off while the warship was underway off the northern Florida coast
The upper part of the mast on the destroyer Gravely broke off Feb. 13 while the warship was underway off the northern Florida coast, the U.S. Navy has confirmed.
"While underway conducting routine operations Feb. 13, USS Gravely (DDG 107) experienced structural damage to the mast mounted antenna. No personnel were injured during the incident," Cmdr. Elissa Smith, a spokesperson for the Second Fleet in Norfolk, said in a Feb. 15 e-mail to Defense News. "USS Gravely's crews took immediate action and secured the damaged mast-mounted antenna. The cause and extent of the damage is unknown.

"The ship safely returned to Mayport, Fla. at approximately 10 a.m. local yesterday and is undergoing assessment. Commander, U.S. Second Fleet and Commander, Naval Surface Force Atlantic are taking prudent actions to ensure safe, efficient and effective repairs to the ship. Naval Sea Systems Command (NAVSEA) is leading the investigation to identify the root cause of the failure."
The Gravely, a DDG 51 Arleigh Burke-class Aegis destroyer, was built by Northrop Grumman's Ingalls Shipyard in Mississippi and is virtually a new ship, having been commissioned last November.
NAVSEA was unable initially to respond to a question as to whether other ships of the Arleigh Burke class have suffered similar damage. The Gravely is the 57th ship of the class, which remains in production.
"The investigation will determine the root cause of the failure and whether similar conditions exist on other ships of the class," said Alan Baribeau, a NAVSEA spokesman in Washington.
A video production crew from Discovery Channel Canada and Exploration Productions in Toronto was on board the Gravely at the time of the incident, working on an upcoming episode of the Mighty Ships series. A spokesman for the company in Toronto declined to comment on the incident.
Judging from a photo produced online by the Web site coltoncompany.com, the break was clean, coming at a weld joining the uppermost part of the mast to a lower part, just above and behind the URN-25 aircraft navigational beacon. The mast appears to have been kept from falling off completely by the electrical cables running inside.

MyNavyBlog2011

-------------------------------
Thursday, February 17, 2011
Job security Shipmate. Via Chris Cavas


Update
What failed was the foundation for the stick mast that gets bolted to the top of the pole mast. As a foundation it is not on the structural drawing for the mast but on a separate foundation drawing for that design zone. As such, i.e. foundation not structure, the weld is considered noncritical and is therefore only subject to visual inspection (VT).

SUPSHIP reviews all UT and above welds, i.e. critical, but looks at only a random sample of VT welds. This should have been caught by the shop foreman. The weld, as executed, was not in accordance with the drawing for that foundation. It is 1" aluminum plate that was to be beveled to 50 deg angle. Note the weld attaching the foundation to the top of the pole mast....the failed weld should have been the same weld.

CDR Salamander
-------------------------------
You do not have the required permissions to view the files attached to this post.
Little h
User avatar
ivorthediver
Posts: 3659
Joined: Fri Aug 10, 2018 8:42 pm
Location: Cambridge Shore Battery

Re: Mast or Antenna - Antenna or Mast

Unread post by ivorthediver »

Never underestimate a Squirrel , if they can find your nuts buried in the ground over the winter period , then faults on board ships are a piece of cake to a Squirrel , ......eh Harry .
"What Ever Floats your Boat"
User avatar
Little h
Posts: 1727
Joined: Sun Aug 12, 2018 6:53 pm

Re: Mast or Antenna - Antenna or Mast

Unread post by Little h »

The following excerpts are taken from:-

Next Navy
Future maritime security


In an article titled In praise of heavy weather and breaking stuff
by Craig Hooper on March 25, 2011

One of the underestimated pieces of infrastructure in the American warfighter’s toolkit is, well, their meteorologists. It’s neat to be able to have an up-to-the-minute global read on the weather, so ships and aircraft can know–at a very, very high level of detail, where to go to avoid tough sea conditions or bad weather.
------------------
But is the Navy over-relying on our meteorological backup?

To some extent, the Navy’s forecasting infrastructure has enabled the development of what I’ll call an operational “Glass Jaw”–that is, the tolerance of operational margins that are insufficient to withstand heavy weather operations.
------------------

Am I the only one to remember that the DDG-51s–the much-loved backbone of the fleet–had some trouble standing up to heavy weather lately? Anybody recall that bow slamming of the USS Gridley (DDG-101)? How the ship, a mere seven months after commissioning and with a single Miami-to-San Diego transit under her belt, suffered “significant” structural damage in 2007? And that the design problem had been known (and likely managed by changing operational parameters for an entire ship class) since 1993?

How quickly we forget.
-------------------
The Navy no longer has sufficient resources to tolerate avoidable quality problems or design shortcomings. Find and fix now to avoid future failures in the dark financial wilderness of the 2020s.

This all leads back to something else that the Navy has not really “dealt” with yet–the bad welding scandals that have plagued the Northrop Grumman yards. Sure, “critical” welds are ok, but when will the bill for the poor-spec “not-so-critical-yet” welds come due? It worries me–and I don’t get the sense anybody in the Navy has really grappled with that stealth maintenance challengebut we needn’t look beyond the recent dis-masting of the USS Gravely (DDG 107) to realize that this unsolved welding scandal is going to end poorly.
-------------------

Source; nextnavy.com (linked above)

_________________________________

My comment; in the article Craig Hooper appears to suggest that the USN has/had a reliance on meteorological forecasts that enabled various assets to avoid bad weather and therefore fulfill operations; and/or other naval activites. Taking that course of action - rather than attending to a course of action that would resolve the/any shortcomings that exist in these platforms/equipment, including:-
a) Osprey de-icing problems
b) how many of our successful Aegis Missile-Defense launches have been held in heavy seas?
c) a heavy-weather-induced hull crack LCS1... and "I expect LCS-2 to endure it’s share of slamming and banging, too"
(then on to the DDG-51 Arleigh Burke class in the penultimate excerpt)

Note; The full article is a very worthwhile read.
Little h
User avatar
ivorthediver
Posts: 3659
Joined: Fri Aug 10, 2018 8:42 pm
Location: Cambridge Shore Battery

Re: Mast or Antenna - Antenna or Mast

Unread post by ivorthediver »

Yes indeed it was a worthwhile read Harry , and thanks for highlighting it for us , At this rate of replication of collisions , breakages of key components its time to bring out the Big Stick and more to the point not be frightened to use it :|
"What Ever Floats your Boat"
User avatar
Little h
Posts: 1727
Joined: Sun Aug 12, 2018 6:53 pm

Re: Mast or Antenna - Antenna or Mast

Unread post by Little h »

Seems that weld has been of sufficient quality to keep the antenna in it's place - surmounting the tripod foremast.

Surely not an example of foul weather avoidance referenced earlier in the thread
.

_______________________________________________


NavyLookout Retweeted

RFANostalgia on Twitter
@RfaNostalgia
5h5 hours ago

.@USNavy vessel USS GRAVELY DDG 107 inbound to @HMNBDevonport on a miserable Plymouth morning.

Seen here at the Western Breakwater and then passing #RoyalFleetAuxiliary @RFATidesurge which is secured to C-Buoy.
D1nEG1kWkAI9w5K.jpg
You do not have the required permissions to view the files attached to this post.
Little h
Post Reply Previous topicNext topic

Return to “Ships/Boats Equipment”