Dynamic Ship Flexure Measurement Program
Abstract
This final report summarizes the results of a recently-concluded dynamic ship flexure measurement program during which data were taken on four naval combatant vessels: USS HORNE (DLG-30), USS REEVES (DLG-24), USS BARNEY (DDG-6), and USS ROBISON (DDG-12). Four optical tracking systems, each consisting of a biaxial automatic autocollimator, reflector, and laser, were used to obtain the measurements. The data consist of a series of 10- to 90- minute recordings obtained under varying conditions of sea state, ship speed, and ships heading with respect to prevailing wind and wave directions. For each run, amplitude time histories were plotted, flexure frequency spectra were determined, and RMS flexure values were calculated. The data, summarized in tabular form, identify the frequency and magnitude of flexure between weapon system elements, and indicate that, under certain conditions, the flexure magnitude can actually exceed current alignment tolerances. This is particularly true for the aft 5 in -54 gun on the DDG-2 class ship. It is anticipated that the results of this program will be used in conjunction with a tolerance study to develop cost-effective mechanical alignment tolerances compatible with the measured flexure. Based on the findings, it is recommended that 2 arc-minutes be recognized as the minimum maintainable RPI tolerance. It is also recommended that no further flexure measurements be made on DDG and DLG-class ships unless a specific need arises.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 24, 1973
- Accession Number
- ADA040740
Entities
People
- D. E. Brunner
- P. G. Shoals