New factory orders for durable goods rose 2.5 percent in February, a sharp reversal from January's 5.9 percent plunge, the Commerce Department said yesterday.

About two-thirds of the increase was attributed to a 7 percent rise in transportation equipment orders, the department said, mostly motor vehicles and aircraft.

Since September, new durable orders have behaved in a roller coaster fashion, rising and falling in alternate months depending on the performance of the volatile aircraft sector.

Durable orders rose 5.9 percent in October, dropped 0.8 percent in November, rose 6.7 percent in December and plunged 5.9 percent in January, the steepest monthly decline in 37 months.

During that period, the monthly average was 1.7 percent increase, the department said.

Durable goods are important indicators of primary manufacturing and wholesale demand and are also a component of inventories - stocks ready for sale.

During February, new orders for durable good totaled $63.8 billion, an increase of $1.5 billion for January. Shipments of durable goods climbed 4 percent to $61.2 billion, the department said.

New orders for the nondefense capital goods sector climbed 23 percent to $16.8 billion, the department said.

Nondefense capital goods are considered a key indicator of future plant and equipment spending, and important element of President Carter's overall economic game plan for 1978.

Primary metal new orders were virtually unchanged from January, but neworders for machinery rose 0.9 percent.