In this paper, numerical simulations are performed to study the phenomenon of flow-induced noise from rectangular jet. In addition, simulations are performed with the addition of forward flight as well as forward flight at an angle of attack. The Detached Eddy Simulation (DES) approach is used to simulate both the jet nozzle internal and external flows as well as the jet plume. This methodology allows the turbulence model to transition from an unsteady Reynolds Averaged Navier-Stokes (URANS) method for attached boundary layers to a Large Eddy Simulation (LES) in separated regions. Thus it is ideally suited to jet flow simulations when the nozzle is included. The radiated noise is calculated using a permeable surface Ffowcs Williams - Hawkings surface integral method. Simulations of a turbulent jet flow from a rectangular nozzle with an aspect ratio of 3 have been carried out. Simulations for both unheated and heated cases are included. The effects of forward flight and jet angle of attack on the radiated noise are also examined. Comparisons are made with available experimental data or empirical databases.