WASHINGTON — NASA’s X-33 experimental rocket may never get off the ground, but the agency nevertheless completed the second of three planned hot fire tests of the vehicle’s two linear aerospike engines July 24.

"It was a good test," said Paul Foerman, a spokesman at NASA’s Stennis Space Center, Miss., where the test took place.

The engines were throttled up in a 25-second firing that commenced at 10:54 p.m. local time.

A final 100-second test is targeted for around the first week of August, Foerman said.

NASA canceled the X-33 reusable launch vehicle prototype program in March, but resumed testing of the vehicle’s pair of experimental engines July 12 using $3.8 million in Space Launch Initiative funding.

NASA officials determined earlier this month that a series of hot fire tests were in order to learn more about the engines’ electromechanical actuators.

The actuators control the flow of fuel to the engines and are considered one of the linear aerospike design’s truly new technologies.

Garry Lyles, manager of the Space Launch Initiative’s Project Propulsion Office at NASA’s Marshall Space Flight Center, Huntsville, Ala., said data gleaned from the hot fire tests should prove useful to the companies developing propulsion systems for a new generation of reusable launchers.