SOS: America's Newest Nuclear-Powered Aircraft Carrier Suffers Breakdown At Sea

A significant manufacturing error on the U.S. Navy’s newest multi-billion dollar nuclear-powered aircraft carrier abruptly ended the vessel’s shakedown cruise at the beginning of this year, Bloomberg reports.

In January, the $12.9 billion USS Gerald R. Ford (CVN-78) aircraft carrier experienced a propulsion system failure, during a period of intense performance tests. The shakedown cruise simulates working conditions for the vessel, which is typical for new ships. According to an internal Navy memo obtained by Bloomberg, the ship’s crew noticed a temperature increase of “92 degrees Fahrenheit above the trust bearing temperature setpoint.”

A thrust bearing is a critical component of the propulsion system of a vessel. It transfers the propulsive energy from the propeller to the ship’s hull, allowing the propeller to push the boat forward. According to the memo, “after securing the equipment to prevent damage, the ship safely returned to port.”

In other words, the +90,000 ton, nuclear-powered vessel experienced a catastrophic failure of its propulsion system. Luckily, the failure occurred on a shakedown cruise and not in enemy waters, because, the ship would have been a sitting duck. The memo said “prevent damage,” that is an indication that engineers advised the captain to shut off the propeller that was connected to the malfunctioning thrust block. This would have resulted in a tremendous reduction of speed as the vessel returned to port.

Interesting enough, the breakdown occurred in Janurary, but recently disclosed after Bloomberg uncovered an internal memo from Naval Sea Systems Command.

“Navy officials didn’t disclose the problem during budget hearings before Congress in recent weeks and House and Senate lawmakers didn’t ask about it,” Bloomberg observed.

According to the memo, Huntington Ingalls, the shipbuilding company responsible for manufacturing USS Gerald R. Ford, expressed to the Navy that the propulsion system breakdown was triggered by a “manufacturing defect” and “not an improper operation” by the crew aboard the ship. Huntington Ingalls declined to state who was responsible for the defective thrust bearing, but Bloomberg noted that an inspection of the parts inside the affected thrust block show that poorly machined gears were manufactured at GE’s facility in Lynn, Massachusetts as the “root cause.”

A representative from GE said the company halted all production of the internal components of the thrust block for the USS Gerald R. Ford, which leaves us with many unanswered questions… The memo said the parts are reportedly “out of spec,” and would need to be repaired or completely replaced. As we mentioned above, there are four propellers with four thrust blocks, which if GE poorly manufactured one thrust bearing, then, are the other three comprised as well?

During the “post-shakedown availability” phase, improvements are generally made while the ship is in drydock. Bloomberg fails to note the extent of the damage nor the turnaround time in bringing the world’s most expensive aircraft carrier back to full operational capacity. There is a reason why the Navy has kept this failure a secret for many months — because it is a complete embarrassment. If the Navy went out of their way to hide this failure, what else are they hiding from taxpayers?

Comments

So Close Slippery Slope Fri, 05/11/2018 - 17:03 Permalink

Thrust bearing... not trust bearing.  And this is why it is called a "shakedown cruise."  Shit happens when you make real things then put them to use in the real world under real conditions.  The tone of this article exemplifies what pussies we have become and why we don't manufacturer near as much domestically as we used to.  We deserve to get taken down a notch or two.  And it is going to happen.  Have a great weekend drinking beer and watching ESPN sportscenter re-runs.

In reply to by Slippery Slope

PocoPete mkkby Sat, 05/12/2018 - 01:00 Permalink

The Japanese have 2 helicopter carriers, the Izumo and the Kaga (not the same Kaga that was sunk at Midway in WWII).

Although primarily helicopter-only carriers, they could be upgraded to support fixed wing aircraft that are capable of STOVLs (short take-off, vertical landing) such as the F35A.  The Izumo class ships displace 19,500 tons empty or 27,000 tons full load and are 250M long.  The Izumo class ships are designed to carry up to 28 helicopters at once.

In reply to by mkkby

PocoPete Manthong Sat, 05/12/2018 - 02:32 Permalink

In addition to hypersonic missiles, the Russians have "wake homing" torpedoes which do not respond to the usual torpedo countermeasures.  These torpedoes can be launched from as far away as 10.8 miles.

To counter the threat of wake homing torpedoes, the US Navy is currently developing a Surface Ship Torpedo Defense System which uses an anti-torpedo torpedo to intercept the enemy torpedo.   Alarmingly, the US Navy does not plan on being able to deploy this system on their high value surface ships until around the year 2035.

In reply to by Manthong

So Close beemasters Sat, 05/12/2018 - 07:09 Permalink

For all the non-navy non-engineering types, the reason there are four shafts and props is there is are no mechanical drives, electric motors, generators, electrical services, etc on the planet big enough to handle the load on a single shaft.  You would also run into cavitation problems on a single prop that big given its diameter, and thus tip rotation speed at the revolutions that would be required to transfer all the horsepower mechanically to the water.  (If you push water out of the way fast enough, and thus lower the partial pressure of the surrounding water below the a vaporization pressure for a given temperature the water literally turns into steam.  Anyone that has gunned a high powered outboard motor, or done the same on an inboard high performance wakeboard or ski boat from low speed or  stop has experienced the "ripping sound" this produces.)    It also gives redundancy in the event of damage (battle inflicted or otherwise.)   The high temp alert on the thrust bearing oil which caused the issue is indicative of imperfections in the bearing race or the bearings themselves, or debris that was not cleaned from the bearing race, or mechanical non alignment. (Perfectly aligning the physical mating of two 3 foot in diameter shafts is no small, or simple thing.)  In any case the additional foreign material or surface imperfections, or differential pressure applied due to physical misalignment cause friction and thus heat, which lead to mechanical breakdown.  The bearings are designed to roll in the race.  If this works as designed it is like a perfect metal ball rolling on perfect metal sheet.  There is little friction and that which is created is absorbed by the oil.  If there is foreign matter between the ball and metal sheet, or small flat spots, divots, or other imperfections on the ball, or imperfections on the metal sheet, or the bearings one side of the circular race are pinched due to misalignment, this cause the ball to slide metal to metal over that spot as opposed to roll.  This creates immense heat given the "weight" on the bearing imposed by the thrust from the prop.  This sliding action also knocks  of more material from the bearing and the bearing race which in turn creates more sliding friction and heat.  If you run this to failure the bearing and metal sheet will literally get so hot they will weld themselves together and seize.  Incidentally this kind of mechanical welding is used in industry.  It is called stir welding and is what SpaceX is using and has perfected to make the huge tanks necessary to hold propellant in their rockets.  

In reply to by beemasters

Burnt To A Crisp The_Juggernaut Fri, 05/11/2018 - 18:37 Permalink

Juggernaut: Anybody who has ever worked with large shafts and thrust bearings knows it is often a very tricky business to get what appears to be a very simple mechanism right. Alignments must be near perfect despite their huge sizes. Welding the thrust bearings housings so they don't pull themselves out of alignment is a very tricky and very complex business even when you know what the hell you are doing! 

Imagine a 3 foot diameter ship's propeller shaft and thrust bearing being out of alignment by one thousandth of an inch over a 3 foot length! Imagine that the 3 foot diameter shaft is driven by say a 20,000 HP engine. Think about how much sideways energy that 3 foot diameter shaft could put on the thrust bearing! Then imagine the shaft rotating once per second! Some of the 20,000 hp instead of smoothly going to the propeller is being vibrated (bashed) against the walls of the thrust bearing! If someone started wacking you with say 1,000 of that 20,000 hp once a second, you would heat up real quick too! Unfortunately repairing these kinds of problems is a very slow and time consuming business! 

In reply to by The_Juggernaut

MarsInScorpio steve2241 Fri, 05/11/2018 - 18:07 Permalink

OK, I bought into the question: What is a knurled flange bracket?

Courtesy of some manufacturing company's web site:

Press-Fit Thread Inserts - Knurled Flange

Use for cored or drilled holes in plastics. Designed to replace molded-in inserts and threads in plastic castings. Provides clean threads and screw locking action not obtainable in molded-in inserts. Saves time and money. Available in brass or Type 303 stainless steel. Recommended for use in terminal strips and like applications in electronic assemblies.

Frankly, why would anyone writing about thrust bearings have any reason to know what a knurled flange bracket is, anyway? They have no relationship whatsoever . . . but I get your point . . . I think . . .

In reply to by steve2241

CRM114 MarsInScorpio Fri, 05/11/2018 - 18:40 Permalink

A knurled flange bracket is the made-up generic name for any seemingly unimportant widget, originally from the comedy section of Flight International (Now Flight Global). Back in the day, anyone who did engineering would know it was a joke item, and therefore a useful test whether anyone did in fact know any engineering.

A bit like finding out whether someone is a foreigner because they think Podunk, Iowa really exists.

In reply to by MarsInScorpio

zimboe MarsInScorpio Sat, 05/12/2018 - 01:32 Permalink

Also known as a swoggle plate, or a frammis bracket.

I once prepared a drawing set for a machine with lotsa various brackets.-I simply named them Bracket 1, Bracket 2 etc.

Then the idiot-stick PHB project leader demanded they must all have functional names. So, hence the above.

Nobody ever asked any questions. Word.

...

I'm the design engineer, dammit. I sez it's a fucken frammis plate, it's a fuken frammis plate. Just follow the damn print and STFU.

In reply to by MarsInScorpio

idahobandito CRM114 Fri, 05/11/2018 - 17:16 Permalink

What a crock of shit fear porn article. It has 4 reduction gear/shafts. this would only slow it down 25% each are individually operated. When we lost a high speed pinion bearing in the burmuda triangle, we were drifting until we replaced it right there in about 1 day, but we only had one "engine" (reduction gear/shaft). That ship is now coral reef. Its nick name was the "turd". G---.

In reply to by CRM114