WASHINGTON — Something odd happened to the US Navy a few days ago. Somewhere between February and March, the fleet lost nine ships.

The web page where the service lists its vital statistics — number of people, number of ships, etc. — showed a fleet of 284 ships as Friday, Feb. 27 came to a close. But on Monday morning, March 2, that same fleet was officially listed as 275 ships.

But no real ships were decommissioned, sold, sunk or otherwise disposed of. So what happened?

In a word, Congress.

The size of the US fleet is a political football all sides like to kick around, usually to their advantage and the disadvantage of the opposing party.

The Democratic administration likes to point out the fleet is growing since it dropped below the 300-ship level in August 2003 — under the administration of President George W. Bush — hitting a low of 275 ships in early May 2007.

Republicans, particularly the House majority, want to portray the Obama administration as weak in providing shipbuilding funds, with dire predictions of a fleet of 240 ships or so.

A year ago, the administration altered the way it counts the fleet, adding in some ships not previously counted, resulting in a jump from 283 ships to 290. Opponents on the Hill cried foul, arguing the Navy was artificially inflating the fleet's size, and inserted language into the 2015 Defense Authorization Act to essentially force the service to return to the old rules. It's those new — uh, old — requirements that the Navy has just implemented.

"Ship counting changes reflect direction outlined in the 2015 act," Lt. Rob Myers, a Navy spokesman at the Pentagon, said on March 6. "The change in the numbers does not reflect an actual change in our ship inventory; rather, what has changed is the counting methodology, which excludes certain ships such as patrol coastal ships and hospital ships. Despite these changes, we affirm our commitment to reaching over 300 ships by the early 2020s and this is reinforced by ship procurement in our 2016 budget submission."

All sides agree on most of the kinds of ships that make up the "deployable battle force," as the fleet is officially described. No is arguing about counting aircraft carriers, submarines, destroyers, or amphibious ships. For the most part, it's the ships on the fringes that are under contention.

In March 2014, the Navy began counting deployed patrol coastal (PC) vessels as part of the fleet total. Although there are 13 PCs, three are stationed in Florida and do not deploy; the other 10 are forward-deployed in the Arabian Gulf. It's those deployed PCs the Navy wanted to count. But opponents said the 380-ton craft, armed with two 25mm guns and crewed by 28 sailors, are too small to count as part of the battle force.

Similarly, the Navy started counting its hospital ships whenever they're deployed, arguing that the strategic purposes achieved by the ships on partnership and humanitarian cruises contributed to battle force aims. Again, opponents cried foul, questioning how a hospital ship could be thought of as a battle force member.

Congress then inserted this language into the 2015 defense act:

"The term 'combatant and support vessel' means any commissioned ship built or armed for naval combat or any naval ship designed to provide support to combatant ships and other naval operations. Such term does not include patrol coastal ships, non-commissioned combatant craft specifically designed for combat roles, or ships that are designated for potential mobilization."

The Navy's written testimony now being presented to Congress in support of the 2016 budget also includes some explanation:

"Navy revised the accounting guidelines for its Battle Force according to requirements set forth in the FY2015 National Defense Authorization Act. Numbers in this statement are not directly comparable to those used in prior testimony, see chart below. The NDAA prohibits inclusion of '…patrol coastal ships, non-commissioned combatant craft specifically designed for combat roles, or ships that are designated for potential mobilization.' Ships that were counted last year, but are no longer counted, are Patrol Craft (PC) and Hospital Ships (T-AH).

Current as of 1 Jan 2015 FY 2016 FY 2020

PB-16: New guidelines 279 282 304

PB-16: Old guidelines 288 291 308"

One of the most immediate upshots of the new counting rules is a change in the way Navy Secretary Ray Mabus and Adm. Jon Greenert, chief of naval operations, introduce the service in congressional testimony, or even in many public appearances. Both are fond of describing the Navy's impact by reading off daily statistics, such as "as of this morning your navy has 284 ships, of which 89 are deployed." The CNO in particular usually puts up a chart with the stats.

But in congressional testimony so far, both officials are avoiding citing exactly how many ships the Navy has — and in two hearings thus far, it seems no one in Congress has taken note.

And it seems the Navy, as described in the notes above, will often be using both counting methods, presented side by side. Depending on your political persuasion, you're free to choose which numbers to use.

Sensitivities over the ship-counting issue are also at the heart of the cruiser debate under way between Congress and the Navy.

The service wants to modernize a number of aging cruisers and sideline them for a time — months, perhaps years. Because of the hot-potato nature of ship counting, they're incredibly sensitive to descriptions of the status of the ships while they're, well, not deploying.

Terms like "decommissioned," "inactive" or "laid up" evoke cries of protests from official sources, since those descriptions could imply the ships are not part of the deployable battle force and hence should not be counted. But service chiefs have yet to come up with a term that satisfactorily accounts for how the ships could be laid up yet still counted as active.

E-mail: ccavas@defensenews.com

Twitter: @CavasShips

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