This paper analyses the causes of an incident in an aircraft propeller hub. The aluminum alloy propeller blade hub was detached from the plane bearing one of its two blades with the other one being jettisoned away. Stereoscopic examination of the fractured hub revealed that it was initially cracked by fatigue. with the crack initiating on the root of the third and fourth spirals and p... https://www.wholisticpet.shop/product-category/novelty-items-greeting-cards/