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Old March 25th 16, 02:59 AM posted to rec.aviation.soaring
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Default Shameless update from Dale Kramer

On Thursday, March 24, 2016 at 7:07:15 AM UTC-7, DaleKramer wrote:
Eric,

Thanks for the support!

Dale


Has NO ONE come forward to challenge my calculations? It has been 3 days and the only rebuttal had something weird to do about having dinner of molds.

Okay, I DID leave something out, and I admit it. I forgot to mention that horsepower from carbureted engines falls off with altitude, so that 100 hp engine will only produce 70 hp at a 10,000 ft DENSITY altitude.

Here is another factoid that you will find if you bother to check my calculations: power required is INVERSELY proportional to the square root of disk area. This is simple physics, so there is NO avoiding it! Consequently, tail squatters require A LOT more horsepower. Dale's design will require nearly THREE TIMES more horsepower than an R22 simply because of the MUCH higher disk loading - that is WHY I made such a point of the HIGH disk loading. I don't have ANY idea where Dale came up with the number of 1.3X thrust to weight, maybe it was in a dream. It seems like engineering analysis is, at best, an after thought. During my career as a design engineer I can assure you we thought of it otherwise.

Here is an interesting quote I dug up from the book by Ray Prouty (Dale, I assume that you ARE reading the reference books):

"Despite the trend for higher and higher disc loadings in the past 20 years, there does seem to be a practical upper limit. Values of more than about 10 pounds per square foot generate such high induced velocities under the rotor that it is difficult to operate from unprepared sites without filling the air full of flying sticks and stones to break one's bones. It also becomes increasingly difficult to obtain safe autorotational characteristics as disc loadings go up. These are two reasons why VTOL aircraft that depend on heavily loaded propellers for hovering have not yet become operational."

And Dale wants the pilot sitting out in the open to be pelted by those sticks and stones. Whatever...