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.
It depends: Changes in fingernails can be indicative of an underlying medical disorder. Ridges or bumps can be related to iron deficiency. Anemia, lupus, heart disease, and thyroid disorders can also can changes to the fingernails. Fungal infection also can cause bumps and discoloration of the nailbed.