Another under-enrolled class of cadets will begin their training at the city’s police academy today, highlighting the employment crisis at the New York City Police Department.

The department expects between 700 and 800 recruits to enter the academy, roughly 2,000 less than hiring goals, according to police officials.

With recruitment goals unmet for both the July 2006 and January 2007 classes, the new class will mark the third straight police academy class that has fallen short of its budgeted headcount.

The department is also seeing a rising number of officers flee the academy. The department’s head of personnel, Chief Rafael Pineiro, said at a city council hearing on public safety last month that the academy’s attrition rate is estimated at 18%. Of nearly 1,350 cadets who entered the academy’s most recent class in January, about 200 failed to graduate last month.

Chief Pineiro said cadets are resigning for several reasons, including academic problems and family obligations. Low pay is a major complaint among cadets, whose salary at the academy is about $25,000 a year.

Police Commissioner Raymond Kelly and Chief Pineiro have said the diminishing numbers of recruits will place a strain on the department, which faces increasing demands to combat terrorism in addition to day-to-day police work.

“The decisions we make about how to utilize our personnel resources assume vital importance, especially when confronting lowered personnel levels,” Chief Pineiro said.

The hiring dilemma will loom larger in coming years as a glut of police officers hired in 1991 for the department’s Safe City, Safe Streets program come up for retirement.