Bygrave position-line slide rule

[a64pilot]

Originally Posted by alan2

I assume Longbow is a program of some kind.Information thereon please.Thanks

Sorry, Longbow is the (D) model Apache helicopter.
The (A) model was essentially a 1970’s design and wasn’t really a true digital design.
The D model, the Longbow brought the aircraft into the digital era and all kinds of things that we used to bring out charts and pencils and interpolate things are now continuously calculated to decimal points and displayed on a screen with way more accuracy that you can get from any chart.

Precise navigation and timing used to be the defining point of mission success, now with GPS it’s simply a matter of programming.

It’s a story of the digital revolution that we see in boats with GPS’s and electronic charting, AIS, anchor alarms that are accurate to a few feet etc. we really know exactly where we are now, always, even in the middle of an ocean, and we know our exact course and speed to decimal points.
What was once a Science fiction story, is now accepted as common place

[alan2]

Thanks for the update.

[Pete17C]

the E6B can also do all your Time/Speed/Distance calcs, and the wind side can be used for figuring CTS in a current (just divide by 10, ie: 60kts on the E6B is 6.0kts for your planning)