gregr75
Member
Hi All,
I downloaded the Roncz spreadsheet from Duncan's RTFM-aero website and the accompanying scanned Sport Aviation articles from 1990/1991. The second article, March1990, last page, says "equations used in the spreadsheets" shows how he got
MAX SPEED = (348.642*horsepower*prop efficiency / (rho*flat plate area))^(1/3)
I get the jist of how max speed depends on the power you have to push a flat plate through the air, but I plugged in known numbers for a Piper Warrior and am getting about 20 knots too fast. Everything else seems to be ok, stall speed, best L/D, etc.
I'd really like to know what aerodynamics formulas he used to get this equation.
https://rtfmaero.files.wordpress.com/2010/10/sav-1990-03r-cc.pdf
Greg
I downloaded the Roncz spreadsheet from Duncan's RTFM-aero website and the accompanying scanned Sport Aviation articles from 1990/1991. The second article, March1990, last page, says "equations used in the spreadsheets" shows how he got
MAX SPEED = (348.642*horsepower*prop efficiency / (rho*flat plate area))^(1/3)
I get the jist of how max speed depends on the power you have to push a flat plate through the air, but I plugged in known numbers for a Piper Warrior and am getting about 20 knots too fast. Everything else seems to be ok, stall speed, best L/D, etc.
I'd really like to know what aerodynamics formulas he used to get this equation.
https://rtfmaero.files.wordpress.com/2010/10/sav-1990-03r-cc.pdf
Greg
