Velocity made good

Velocity made good, or "VMG," in sailing and specifically yacht racing, is the component of a sailboat's velocity that is in the direction of your mark. The concept is useful because a sailboat often cannot, or should not, sail directly to a mark to reach it as quickly as possible. Sailboats cannot sail directly upwind. It is usually less than optimal and can be dangerous to sail directly downwind. Instead of sailing toward the mark, the helmsman chooses a point of sail that optimizes velocity made good.

Concept

Boats cannot sail directly into the wind, requiring the sailor to alternate between headings, which are commonly called "tacks." On a tack, the sailor will generally point the sailboat as close to the wind as possible while still keeping the winds blowing through the sails in a manner that provides aerodynamic lift to propel the boat. Then the sailor turns slightly away from the wind to create more forward wind pressure on the sails and better balance the boat, which allows it to move with greater speed, but less directly toward the mark.

VMG 1927

The VMG 1927 is a light machine gun designed by Heinrich Vollmer.

In 1916 Heinrich Vollmer began working on a design of a light machine gun. At the end the weapon was known as a MG Vollmer, later also as VMG 1927.

It consisted of only 78 parts while the standard MG of those days, the MG 08/15 consisted of 383 parts. It operated on the principle of short recoil with a rotary locking mechanism for the bolt, carried by helical grooves. It was fed from a small drum magazine underneath the receiver.

In 1927 Vollmer also obtained a patent covering the breech mechanism of the weapon. Later on, Vollmer co-developed the gun with Mauser Werke as the MV 31 (Mauser-Vollmer 1931). It was offered to the German ordnance board (Inspektion für Waffen und Gerät - IWG) but, after testing, it was not adopted for service. This guns had a quick-change barrel and used a drum magazine.

Two exemplars are known to exist, one is at the Wehrtechnische Studiensammlung Koblenz and the other at the Vojenský historický ústav Praha.