The first two loss-of-coolant experiments have been performed in the Loss-of-Fluid Test (LOFT) Facility. The experimental results are compared to analytical model results from the RELAP4 computer code. LOFT is a pressurized water reactor specially designed and instrumented to perform experiments representative of a loss-of-coolant accident (LOCA) in a power reactor. For these first two experiments, the nuclear core was not installed in LOFT. The first experiment was initiated from a pressure of 9.3 MPa with water at 282/sup 0/C, and the break represented a half-size double-ended offset shear in the hot leg of a power reactor. The second experiment was initiated from a pressure of 15.3 MPa, a temperature of 282/sup 0/C, and simulated a complete double-ended offset shear in the cold leg of a power reactor. In the first experiment, emergency core cooling was injected by low-pressure, high-pressure, and accumulator emergency core cooling systems at times representative of what would occur in a LOCA in a power reactor.