The props database (PROPS.EDB) characterizes propellers.
MANUFACTURER is a description of the type of propeller and manufacturer (up to 20
K prop is a propeller constant used in calculating the power absorbed by a
propeller. It indicates the manufacturer's generic prop shape and its effect on power.
A prop with a higher K prop absorbs more power for a given diameter and pitch.
This number is difficult to measure, and much of the data is empirical.
However, there is substantial variation in prop factors (usually pitch) in what you
buy which often overshadows the accuracy of other numbers.
K pitch is a propeller constant used in calculating the power absorbed by a
propeller. It is used basically to compensate for the absorbed power consistently
being less (or greater) than the equation would indicate based on the pitch as
stated by the manufacturer. A positive K pitch indicates that the power absorbed
is less than the calculation based on the stated pitch.
K eff is a coefficient to account for efficiency differences between props, e.g.
2- vs. 3-blade. This coefficient is new to Version 2. The coefficient Kpitch
from Version 1 is still used but can only be changed with the database Edit function.
COMMENTS are allowed at the end of the line.
PTR is a somewhat bizarre alphanumeric pointer assigned to this data entry for
reference by the Planes database. There is a small chance that two entries will
have the same pointer and thus "confuse" the program into selecting the wrong
one. This can generally be fixed by making a slight change in the description.