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Throughout various experiments on the system, the rocket's body exhibited signs of unstable flight and inconsistent dispersion. This made prediction of its flight path extreme difficult. In one trial test an accident occurred. A rocket had exploded within the launcher frame, causing all other rockets to explode simultaneously — An undocumented incident just short of a total disaster. This incident had a great impact on the system's development and nearly jeopardized the existence of the whole project. During the 1980s, military funding was so scarce that a single mishap could have proved one too many.

The 273mm system had to contend with an extended range 122mm 40 barrel MRL from No.5137 Manufacturing Plant. The improved 122mm system, which later become the Type 90 MRL, also has a 40km range and it was in early development during the same time. However, despite much debate, work did continue based on the argument that the PLA in need of large caliber rocket artillery system for fire support and to compensate the lack of short-range tactical ground-to-ground missiles. In addition, the 273mm rockets have much more growth potential for range, payload and warhead types than the smaller 122mm system.

Due to the non-satisfactory test results, a lengthy investigation identified two major problems with the system:

(a) Range accuracy Ex/x = 1/33.7 (2.9% of range) during high temperature environment of + 50° C is worse than at standard temperature. Not only so, it is much lower than that of low temperature at -40° C, where its accuracy is Ex/x = 1/83.8 (1.1% of range, nominal for fin-and-spin stabilized rockets). Such condition demonstrated unacceptable abnormality ballistic performance.

(b) Data from a high-speed range camera in one of trail, shown the active flight phase of the four rockets, that is, an in-flight period when the main rocket is still functioning, the rockets from the most left and most right hand side of the launcher crossed each other’s path in-flight. Again, this is an unusual abnormality, and an indication of grossly unacceptable performance in azimuth dispersion.

The designers reckoned these two abnormalities should be treated together as one issue. Regarding the problems with low accuracy at high temperature and trajectory path crossing, investigation centered on the launcher rather than the rocket. They had discovered that, after the rocket's ignition, it completely left the launch rail and the stabilizer apparatus of the rectangular frame launcher had shown lateral vibration. This explained the path crossing of the rockets. And because vibration from the launch frame on both sides of the launcher was greater than those two in the middle, path crossing was more apparent. Later, researchers found out that movement of the stabilizer apparatus of the launcher was due to its frame structure design. During firing, gases from each launch frame producing a lateral force which then interacted with each adjoining structural components to rock the whole launch platform. This problem was exacerbated by gas pressure from the rocket's spin motor and main motor where their force vectors were in opposition. Further analysis also suggested this was also the cause for low accuracy under high temperature environments.