In 1971 VR-30 joined the Jet Age with two North American CT-39 Saberliners for high-speed executive airlift. In May 1973 the squadron received the first of four C-9B Skytrain II's to further improve its logistics support capability.
Vertical ridges can also be caused by nail injury and certain diseases, including rheumatoid arthritis, according to Rich. If, instead of a series of ridges, there's a single vertical streak, cautions Krant, this could be a sign of a tumor growing at the root of the nail.
Mainly aging: Increase in vertical ridges of the fingernails as age, and this can be a normal development. Onychorrhexis is the medical term used to describe longitudinal ridges on the nails that often accompany brittle nails.Trauma may also be a cause of nail ridges. Nutritional causes such as vitamin deficiency less common. ...Read more.