M-V-5 M-34 Extendible Nozzle Function Test

The function test of the M-34 extendible
nozzle of the M-V-5 rocket was conducted in the Structure and Mechanics
Building from May 27 through 31.

The purpose of this test was to verify the sound functioning of the actual
M-V-5 rocket. Due to the restricted testing conditions, the test of extending
the nozzle and that of jettisoning the DHS (double helical spring) after
extension were conducted separately.

In the nozzle extension test, resistance of sliding and locking systems,
the performance of the Marman band that fastens the nozzle extension system
and the performance of sliding rails at jettison were investigated and
extension speed and distortion data was obtained.

In the DHS jettison test, the performance of the Marman band that fastens
the DHS and its interference to the nozzle at the time of jettison were
investigated, and data on jettison speed was obtained.

Although the pyrotechnics did not ignite due to insufficient ground coordination
in the first extension test, the rest of the testing proceeded smoothly
as the problem did not cause any complications to the actual rocket. Excellent
data was obtained, demonstrating high consistency with the data acquired
in the past testing from development tests to function tests on the three
rockets with flight experience.

With these results, the M-34 extendible nozzle will go on to the next
step, a coupling test, followed by the first and second assembly operations,
and finally to a flight test scheduled in November.