1. The test articlewas fabricated ineight parts. The body consisted of four sections manufactured from 6061-T6 aluminum. The nose, both leading edges, and the main cavity cover plate were manufactured from 17-4 PH stainless steel The final step was hand finishing of the surfaces to remove tool marks A photograph of the model mounted in the tunnel is shown in Figure 4.
2. The force balance used for this test program was an Able Corporation 1.5 inch Mk 34a with thc Tunnel 9designationof 9HV6-3. The maximum load ratings for this balance were as follows:
3. Normal force: 2000 Ibf Yaw force: 500 Ibf Axial force: 600 Ibf Roll moment: 800 in-lbf Pressure Instrumentation
4. Pressures were measured at 32 locations on the model: 24 on the body and eight on the base. The body pressures were arranged along rays emanating from the model nose and confined to the left half of thc model. This isillustrated inFigures 5(A-C). The locations of the base pressure taps are shown in Figure 5(D). With two exceptions, all pressure taps on the model used stainless steel tubing with an inside diameter of 0.062 inch. The gauges were Kulitc model XCW-062-5A transducers and were connected lo the taps with short lengths of flexible Tygon tubing. These transducers have a nominal rating of 5 psia. Tubing lengths were limited to one inch or less in order to minimize lag, as outlined in Reference 3.
5. The exceptions were two transducers located along the bottom centerlinc at 20% and 70% of the body length. These gauges ivere Kulite model XCW093-15A transducers, nominally rated at 15 psia. They incorporated special screens consisting of a single pinhole, 0.031 inch in diameter, and were mounted flush with the external surface. This was donc in order to study the spectral content of the pressure signal. The results of this effort will be rcportcd under separate GOYCI. Ilcat-Transfer Instrumenta 1'ion