<VV> Rocket Scientists

[Padgett]

> > From that, it seems to me that the bottom line is that so far nobody has
> > been able to do better at home than the GM automotive engineers did in
> > Detroit.  I suspect that that status will continue.

Is this when I might mention that while my ME/EE degree came from GMI 
shortly after the demise of the Corvair, I really learned about 
compressible fluid flow (particularly transonic) at Pratt & Whitney GPG ? 
There is an old saw about "Nothing is worse than an expert out of their 
field" and other than Electromotive division, few at GM were into air 
cooling (the story of Boss Kettering's air cooled engine of 1921 and the 
politics that killed it were still in senior GM executive's memory 40 years 
later) . It is further evident that one of the prime factors in the design 
of the Corvair fan was ease of production with minimal machining and cost.

Modern equipment (and I have better test equipment in my garage at home 
today than I ever had at Pratt, a quick way to tell which cyl is missing is 
with an IR digital thermometer - $60 from harbor freight -) Yes, thems were 
the "good old days" but would not trade for a New York minute what we have 
available in test equipment today. Will say that scanning a test run for 
anomalies is a whole lot easier on a laptop than finding a corridor long 
enough (and is one a mile long in Ft. Worth)  to roll out the Brush charts 
and scan with a MK 1 eyeball.

Bottom line, any modern fan (including a propeller or the fan in a CF-56 or 
the sub props leaked to the Russians that helped win the cold war) today 
has computer designed blades and they are not straight.

What this means is that the fan and shroud for this century would be of 
composite material have a much different appearance, and would move enough 
cooling air with an energy budget of around 2 hp. Further the vents behind 
the rear window would be gone because that is a low pressure area (would be 
interesting to instrument the engine compartment above the shroud at 70 mph 
- anyone ever do that ?) Instead the engine would probably be a bottom 
breather and use baffles to create a high pressure area at the fan inlet 
and a low pressure area under the engine.

The current design tries to do this by positioning the air exit at the rear 
where the underbody airflow will provide an assist. That the engine cools 
better with the lower shroud removed says this thinking was faulty.

So the engineers in Detroit, Tonowanda, and Waterford in the 60's were 
doing the very best they could given the constraints they were working 
under. However even a decade later at GMI I was able to get all of the 
computer time on the 360 mainframe I wanted because few others were using 
it. Nothing like a mainframe for brute force calculations of all possible 
ratios for a THM-400 or simulating over 1 gee excursions with a B/P 
Corvette, somthing we can do on a PC in seconds now but took overnight then 
(and one of the first things a programmer learned, after the proper use of 
a magic marker, was how to increase priority and get unlimited runtime). 
Have forgotten JCL three times now and hope it stays that way.

Padgett