mechanism to the uneducated individual. To the educated, an aircraft

propeller represents the highest sophistication in aerodynamics,

mechanical engineering and structural design. This report will touch

on the history of the propeller, from early pioneers/experiments,

advancement during/after the war, all the way up to current

applications of the propeller. The creation of the propeller can be

traced back to Leonardo da Vinci. Da Vinci's "helical screw"

helicopter is believed to be the ancestor of the air propeller and the helicopter rotor. The first idea of a propulsive airscrew, however, belongs to J.P. Paucton, a French mathematician. Paucton

envisioned a flying machine that had two airscrews, one for propulsion and the other for sustaining flight. The idea of using an airscrew for propulsion was utilized during the late 1700's to early 1800's. Only after experimentation did the inventors conclude that more propulsive power could be obtained by merely straightening out the surface of the airscrew blades. Attempts to utilize the "straight blade" propeller were made by balloonists. These contraptions were quite strange and hardly fulfilled the

electrical blade deicing. Many large propeller transports switched to

foundation of aerodynamic principles that were essential to the

"un-ducted fan". This design incorporates the reliability of the

wide, super-thin, hollow blades to increase the performance of the

that had twin 12ft propellers with 6 blades each! Interestingly enough these blades could be adjusted to produce maximum thrust under certain conditions, an early recognition of the need for changing blade pitch. Without a doubt, the most expensive and spectacular project of its time was that carried out by Sir Hiram Maxim. His numerous experiments with propellers, culminated in the construction of a huge, four-ton biplane in 1890. This contraption was powered by two 180hp steam engines that each drove propellers 17ft, 10inches in diameter and weighing 135lbs. The two-blade propellers,inversely tapered and squared at the tips 5 1/2 ft wide, were made of American Pine, planed smooth, covered with glued canvas and stayed to the propeller shafts with steel wire to handle the high thrust loads. These massive propellers produced 1,100lbs of thrust each during full power while rotating at 425rpm. Maxim's jumbo creation didn't last long however, it jumped the test track and suffered extensive damage. Hands down, the most influential aviation pioneers were the Wright brothers. They had concluded that a propeller was simply a whirling wing, but didn't have the appropriate information to consult when comprehending the fundamental principles of blade shape. This dilemma made designing the propeller one of the Wright brothers most challenging problems. Despite the lack of previous information to consult, the brothers were able to learn, through investigation and trial/error, that large propeller diameters would produce high thrust for a given power input. The brothers also determined that high torque produced by large, slow turning blades adversely affected the flying qualities (p-factor). On their first aircraft, they utilized 8 1/2 ft propellers installed behind the wind to minimize airflow disturbance, incorporated counter-rotating propellers to eliminate the problems associated with torque, and gained thrust efficiency by reducing the blades' rotational speed using a chain an

Some common words found in the essay are:
Turnbull Turnbull, American Pine, Hamilton Standard, Paucton French, Lucien Chauviere, History Propeller, Hiram Maxim, La France, Thomas Moy, Da Vinci's, metal propeller, adjustable propeller, wright brothers, hamilton standard, ground adjustable, variable pitch, da vinci, history propeller, pitch propeller, airship la france, la france, variable pitch blades, ground adjustable propeller,
Approximate Word count = 1520
Approximate Pages = 6 (250 words per page double spaced)