[RVRC] Interesting

[Bryan D. Boyle]

On 6/13/11 12:10 PM, Prof Bob Hopkins wrote:
> Well,
> It is only accurate to three significant figures, but it needs no wall
> wart to recharge it, and usually will still function if you spill beer
> all over it.  And was used in the design and construction of most major
> engineering marvels before 1960.  I still show the future engineers how
> to use one of these things.  Not that they really do anymore.
> 73,
> bob
> wb2udc
Anyone who took private pilot ground school classes with me at Princeton 
Airport was instructed in the use of the E6B, which is the aviation 
circular slide rule version (I have one on my watch, fwiw) of this 
venerable device.  Batteries never wear out (usually in the dark, in 
bumpy weather, off course, etc), you can do repeatable calculations 
using constants rapidly, and, for the calculations we usually need to do 
in flight...are accurate enough (I mean, unless you're doing 
micro-whatever, do you REALLY need more than 3 significant digits to the 
right?) for the t/s/d, time to point, or time over distance, etc 
problems that most folks have to work.

Many of the *ahem* more mature students used them with glee and became 
reacquainted with the use of the rule, even (to the amusement of the 
flight test inspector) to the point of using them on the flight test.

I still have a small collection of rules (no surprise there...), and for 
quick calculations, they give instant results as well as a visual 
representation of the ratios between the numbers.  But, I think I'm 
preaching to the choir.

Consider...we sent men to the moon and these were, at the desks, de 
rigeur tools in the hands of engineers...;)

Drew: I'll take a photo of a manual Royal I have...:)

-- 
Bryan
In this world, you must be oh so smart or oh so pleasant.
Well, for years I was smart. I recommend pleasant.
You may quote me.