Assertion: spacecraft's engine | /r/HasProperty | tested on suborbital flight
Facets:
value: aboard the space electric rocket test
type: LOCATION
value: in 1964
type: TEMPORAL
Source sentences:
text: Suborbital tests of the engine followed during the 1960s, and in 1964 the engine was tested on a suborbital flight aboard the Space Electric Rocket Test 1 (SERT 1).