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Effects of targeting pod modification on F/A-18C Hornet weapons release

Published online by Cambridge University Press:  27 January 2016

C. W. O’Brien
Affiliation:
Department of Mechanical Engineering, United States Naval Academy (USNA), Annapolis, USA
M. R. Snyder
Affiliation:
Department of Mechanical Engineering, United States Naval Academy (USNA), Annapolis, USA
E. N. Hallberg
Affiliation:
Department of Aerospace Engineering, USNA, Annapolis, USA
A. Cenko
Affiliation:
Store Separation Consultant, Dunkirk, Maryland, USA

Abstract

This paper describes a study that investigated the efficacy of modifications to the trailing end of the externally mounted advanced targeting forward looking infrared pod (ATFLIR) on the store separation characteristics of the F/A-18C aircraft. Prior work by Godiksen suggests that the trailing end of the geometrically similar targeting forward looking infrared pod (TFLIR) is the likely source of shock waves that can adversely impact the trajectory of a recently released store. In our study five different modifications to the aft end of the ATFLIR were analysed using computational fluid dynamics (CFD). The two most promising designs, an ogive shape such as that used in artillery shells and rockets, and a simpler extended but truncated cone shape were then further investigated. The moments that these trailing shapes produced on an adjacent released store were compared. CFD analysis revealed that the simpler cone shape resulted in weaker shocks from the aft end of the pod with a resultant smaller adverse moment on the store. While there is an extensive history of using CFD to predict store separation behavior, results from our study should be compared with wind tunnel data in order to validate the CFD simulations.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2012 

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