Here is an excerpt from a National Transportation Safety Board Aircraft Accident Report… Research has shown that fundamental frequency (pitch) can convey information about a speaker’s psychological stress. With regard to fundamental frequency, the Safety Board used the following guidelines from two previous accident investigations… Read more
I have posted a Vibrationdata Newsletter with an aviation theme at: http://www.vibrationdata.com/Newsletters/August2011_NL.pdf The articles include discussions of . . . 1. The XF-84H turboprop aircraft which had supersonic blade tip velocity 2. Aircraft landing shock 3. Turbofan engine buzz-saw noise Military Aircraft Carrier & Normal… Read more
Here is a survey question. NASA-HDBK-7005(2001) gives the Franken method as a semi-empirical method for predicting the vibration response of a cylindrical skin to an acoustic pressure field, via extrapolation. Franken originally published this method in 1962 based on rocket engine static test fire data.… Read more
I recently had a need to compare sound pressure levels (SPLs) on the inside of payload fairings for a number of launch vehicles. These levels are readily available in online user’s guide for vehicles such as Atlas, Delta, Falcon, Ariane and others. The most critical… Read more