Drogue Chute Towing Test 2021.11.25-26
On November 25 and 26, we conducted tests to confirm the strength of the drogue chute of WIRES#015 using the training ship “Nagasaki Maru“ with the cooperation of Nagasaki University.
Since it is difficult to reproduce the maximum dynamic pressure in air, the required load can be applied by deploying the drogue chute and towing it in water where dynamic pressure can be easily obtained.
Two types of tests were conducted off the coast of Nagasaki. One was the underwater static load test in which the drogue chute was towed in the deployment state, and the other was the underwater impact load test in which the drogue chute was deployed underwater to simulate an opening shock.
In the underwater static load tests, it was confirmed that there was no damage that would impair the function of the chute even when it was loaded with 33.8 kN, which is more than the operational maximum load of 29.9 kN.
On the other hand, the underwater impact load test was not performed because the towing speed was insufficient.
In addition, shock absorbers and sliders were installed to attenuate the opening shock. However, since the shock absorber was not loaded as a shock load, we could not confirm the expected shock attenuation effect of these. We will investigate and study this issue in the future.
Since we were able to confirm from the test results that the drogue chute has the required strength, the high-strength drogue chute used in this test will be installed on WIRES#015. The shock attenuation mechanism will be tested separately in the future.