Overview

This nozzle was designed and built after the failure of the first 4-grain nozzle. It recessed the throat into a thicker portion of the nozzle to reduce stress in the nozzle. It survived the catastrophic failure of XB-98-4G #2 and the successful static fire of XB-98-4G #3. The throat was .88 in after two firings.

Prior to the test of OW-98-FIN1 the nozzle was modified to have a throat diameter of .98 in and a second o-ring groove was added for redundancy.

After the OW-98-FIN1 #1 static fire the nozzle was cracked. The extraction process further damaged the nozzle. The throat was actually shrunk due to slag deposition to .96 in. The nozzle extraction process was "energetic" and the lower o-ring gland was cracked during this process. A single large radial crack was present in the converging section of the nozzle. Due to the lack of slag in the crack, it is theorized that the crack appeared during the cool down of the case and nozzle.