While proposed U.S. Navy aircraft procurement funding is set to hold steady in fiscal 2014, the service’s aircraft depot maintenance accounts are slated to take a nosedive and maintenance backlogs will balloon.

Navy spending for aircraft procurement has remained relatively flat—$17.6 billion in fiscal 2012, $17.1 billion in fiscal 2013 and $17.9 billion proposed for fiscal 2014—according to the service’s proposed fiscal 2014 spending proposal.

Meanwhile, aircraft depot maintenance, which dropped from about $1.17 billion in fiscal 2012 to about $1.16 billion in fiscal 2013, is proposed for another dip to about $916 million for fiscal 2014.

The decrease carries with it some alarming trends.

First, the percent funded of the total requirement is similarly dropping—from 100% in fiscal 2012 to 94% in fiscal 2013 to 79% in the proposed fiscal 2014 spending plan.

That all correlates to a growing backlog of work that needs to be done.

For example, the yearly backlog of airframes jumped from one in fiscal 2012 to 14 in fiscal 2013 and then catapults to 206 for fiscal 2014.

For engines, it’s much the same—with a backlog of 11 in fiscal 2012 to 273 in fiscal 2013 to 532 in fiscal 2014.

The fiscal 2014 backlog numbers appear to be well above the “manageable” levels cited by the Navy.

“The fiscal 2014 budget provides optimized capability within fiscal constraints,” the Navy says in budget documents. “Additional supplemental funding would increase the funding percentage and decrease the yearly backlog.”

The airframe maintenance workload is calendar-based, while engine maintenance is based on planned flight hours. Any airframe or engine not completed from the previous years are carried over as backlog and are not ready for use until repaired.

A one-year backlog is the threshold for what can be effectively accomplished with no additional tooling, equipment or space, the Navy says.

“The manageable one-year backlog is about 100 airframes and 340 engines across the active and reserve components,” the Navy says in budget documents. “But the actual threshold varies according to the mixture of type/model/series.”

When it comes to procurement, the Navy is keen on the EA-18G Growler — the service wants to buy 21 of the jamming aircraft in fiscal 2014 for about $2 billion, compared to the 12 procured in fiscal 2013 for about half that amount.

“There are a lot of changes for the F-18s,” Rear Adm. Joseph Mulloy, ssumed deputy assistant Navy secretary for budget, said April 10 during a briefing on the Navy’s fiscal 2014 plan. “Most of it is good news if you’re Boeing.”

The Navy also is proposing a cut in MQ-8 Fire Scout spending to about $61 million in fiscal 2014, compared to about $124.6 million in fiscal 2013. The service is now evaluating what Fire Scout attributes it needs for deployment on later-model Littoral Combat Ships, Mulloy says.

The Navy also is buying 16 more P-8A Poseidons for maritime patrol antisubmarine warfare for about $3.8 billion, which is three more aircraft that requested in fiscal 2013, which included 13 P-8As for about $3.3 billion.

For continuing, through-the-day coverage of the U.S. budget rollout, Aviation Week Intelligence Network subscribers should click here to visit our Fiscal 2014 budget digest page often, where the Aviation Week editorial team will post expert coverage and analysis.