The Cooper-Harper rating scale is a set of criteria used by test pilots and flight test engineers to evaluate the handling qualities of aircraft during flight test. Test pilots are Aviators who fly new and modified Aircraft in specific maneuvers allowing the results to be measured and the design to be evaluated Flight test is a branch of Aeronautical engineering that develops and gathers data during flight of an aircraft and then analyses the data to evaluate the flight characteristics The scale ranges from 1 to 10, with 1 indicating the best handling characteristics and 10 the worst. The criteria is evaluative and thus the scale is considered subjective.

Background

Development

After World War II, the various U. World War II, or the Second World War, (often abbreviated WWII) was a global military conflict which involved a majority of the world's nations, including S. military branches sent different models of their operational aircraft to the Ames Aeronautical Laboratory located at the Moffett Federal Airfield in Mountain View, California for evaluation of the plane's flight performance and handling qualities. NASA Ames Research Center (ARC is a NASA facility located at Moffett Federal Airfield, which covers 43 acres at the borders of the cities of Mountain View Moffett Federal Airfield, also known as Moffett Field, is a joint civil-military Airport located 3 miles (5 km north of Mountain View, in Santa The laboratory was operated by NACA, the predecessor of NASA. The National Aeronautics and Space Administration ( NASA, ˈnæsə is an agency of the United States government, responsible for the nation's public space program Most of the flights were conducted by George Cooper, Bob Innis, and Fred Drinkwater and took place at the remote test site at the Crows Landing Naval Auxiliary Landing Field in the central valley area east of Moffett Field.

What may be the most important contribution of the flying qualities evaluation programs and experiments conducted on the variable stability aircraft at Ames was George Cooper's standardized system for rating an aircraft's flying qualities. Cooper developed his rating system over several years as a result of the need to quantify the pilot's judgment of an aircraft's handling in a fashion that could be used in the stability and control design process. This came about because of his perception of the value that such a system would have, and because of the encouragement of his colleagues the in United States and in England who were familiar with his initial attempts. The United States of America —commonly referred to as the England is a Country which is part of the United Kingdom. Its inhabitants account for more than 83% of the total UK population whilst its mainland

Cooper's approach forced a specific definition of the pilot's task and of its performance standards. Furthermore, it accounted for the demands the aircraft placed on the pilot in accomplishing a given task to some specified degree of precision. The Cooper Pilot Opinion Rating Scale was initially published in 1957. Year 1957 ( MCMLVII) was a Common year starting on Tuesday (link displays the 1957 Gregorian calendar) After several years of experience gained in its application to many flight and flight simulator experiments, and through its use by the military services and aircraft industry, the scale was modified in collaboration with Robert (Bob) Harper of the Cornell Aeronautical Laboratory and became the Cooper-Harper Handling Qualities Rating Scale in 1969, a scale which remains the standard for measuring flying qualities. Simulation is the imitation of some real thing state of affairs or process Year 1969 ( MCMLXIX) was a Common year starting on Wednesday (link will display full calendar of the Gregorian calendar.

Awards

In recognition of his many contributions to aviation safety, Cooper received the Admiral Luis de Florez Flight Safety Award in 1966 and the Richard Hansford Burroughs, Jr. Year 1966 ( MCMLXVI) was a Common year starting on Saturday (link will display full calendar of the 1966 Gregorian calendar. , Test Pilot Award in 1971. Year 1971 ( MCMLXXI) was a Common year starting on Friday (link will display full calendar of the 1971 Gregorian calendar. After he retired, both he and Bob Harper were selected by the American Institute of Aeronautics and Astronautics to reprise the Cooper-Harper Rating Scale in the 1984 Wright Brothers Lectureship in Aeronautics. The American Institute of Aeronautics and Astronautics ( AIAA) is the professional society for the field of Aerospace engineering. Year 1984 ( MCMLXXXIV) was a Leap year starting on Sunday (link displays the 1984 Gregorian calendar)

Future replacement scales

While the Cooper-Harper scale remains the only well-established scale for assessing aircraft handling qualities, its unidimensional format lacks diagnostic power and has also been criticised for exhibiting poor reliability. The Cranfield Aircraft Handling Qualities Rating Scale (CAHQRS), developed at Cranfield University's School of Engineering, is a new evaluative system that is multidimensional. Cranfield University is a British postgraduate University based on two Campuses with a research-oriented focus It was developed by combining concepts from two previously established scales, the NASA-TLX workload scale and the Cooper-Harper. A series of validation trials in an engineering flight simulator with a range of control laws showed that the CAHQRS was at least as effective as the Cooper-Harper scale. However, the CAHQRS also demonstrated greater diagnostic ability and reliability than the Cooper-Harper. This new scale's acceptance by the aerospace industry at large, though, remains to be demonstrated.

Scale

Cooper-Harper rating scale flow chart

References

• NASA history of the scale's development
• NASA graphic of the Cooper-Harper rating scale flow chart
• Cranfield Aircraft Handling Qualities Rating Scale information