Rosetree Media School District 1 article published in JoVE Bioengineering Investigating Stress-relaxation and Failure Responses in the Trachea Anita Singh1, Tanmay Majmudar2,3, Adi Iyer4, Diya Iyer4, Sriram Balasubramanian3 1Department of Biomedical Engineering, Widener University, 2Drexel University College of Medicine, 3School of Biomedical Engineering, Science and Health Systems, Drexel University, 4Rosetree Media School District The present protocol determines the tensile stress-relaxation and failure properties of porcine tracheae. Results from such methods can help improve the understanding of the viscoelastic and failure thresholds of the trachea and help advance the capabilities of computational models of the pulmonary system.