ALRO 200R. Made in The Hague, Holland. Circular slide rule consisting of two discs, the outer one of which rotates. It is set in a metal box which, when opened, can double as a desk stand. It has a spiral log scale printed on paper on the lid of
Aristo MultiTrig
Artisto MultiTrig Slide Rule Table Model. Made in Germany by Dennert and Pape, Hamburg. Materials: Astralon and Plexiglass. The factory produced all kinds of slide rules and scientific precision instruments for more than a century. Among others: the DR-2 Flight Computer. Production was abandonned in 1978.
E6-B Flight Computer
The E6B is a form of circular slide rule used in aviation. They are mostly used in flight training, but many professional and even airline pilots will still carry and use their E6Bs. E6Bs are used during flight planning (on the ground before takeoff) to aid in calculating fuel burn, wind correction, time en route, and other items. In the air, the E6B can be used to calculate ground speed as well. The back is designed for wind correction calculations, i.e., determining how much the wind is affecting your speed and course. The circular slide rules are usually made out of aluminum and plastic.
Mercator Flight Computer
Left below: the Mercator Flight Computer which slightly differs from the more expensive E6-B. Below we have a circular aviation sliderule: a Drift Angle Computer to compensat for side winds during constant air speed.
To the right: Circular cardboard metric pressure converter for kilopascal & megapascal ISO, kilogram-force/sq. centimeter ISK and bar ISB. On the backside: Diving Industry Converter for feet of seawater and metres of seawater with caisson and standard depth gauges.
To the left: Three handy-ready pocket slide rules in leather cases. From left to right: Aristo single sided, Faber Castell with an addiator on the back side and Aristo 803.
Ecobra 1600
Ecobra 1600. Metall Slide rule. Collector's item.Very robust. Made of aluminum.
