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Practical Performance Analysis of a Test Flight SCENARIO: Performance and stability factors of an aircraft depend upon numerous variables, all of which need to be fully investigated during the design phase of aircraft manufacture

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Practical Performance Analysis of a Test Flight

SCENARIO:

Performance and stability factors of an aircraft depend upon numerous variables, all of which need to be fully investigated during the design phase of aircraft manufacture. In order to fully comprehend the factors involved, you have been instructed to analyse some of the design factors by applying knowledge following a practical flight.

 

The aircraft in question is operated by RS Aerospace whereby the aircraft has been modified to include additional instrumentation for data gathering through various stages of flight. A data logger and camera combine to provide the information for analysis.

 

Tasks:

Task 1 (Theoretical Analysis) Part A

The primary aircraft for test analysis is the Eurostar microlight. You are tasked with determining a theoretical drag polar for the using techniques of your choice - this can be achieved in several ways:

?             Mathematical modelling – Researching of individual CDo formulae for several parts of the aircraft using the Eurostar AMM and other dimensions;

?             Computational modelling – Researching aircraft dimensions to achieve drag values. Industry standard software such as CAD, CFD and other simulation can be used to achieve parts of the end result.

 

All working should be clearly presented with the final answer given in the form of the linear frag polar equation (?? = ? + ??2), where a and b are numerical values

(typically less than 1).

 

Part B

Using the theoretical drag polar equation from Part A, determine the following performance values for the Eurostar at the following conditions:

?             CL value at minimum drag speed (VMD);

?             CL value at minimum power speed (VMP);

?             CL value at maximum speed to drag ratio (VV/D);

?             Optimum L/D ratio;

?             Maximum rate of climb (?/?);

?             Best angle of climb (????);

?             Stall speed for the aircraft (Vs);

?             Generate a drag curve for the Eurostar.

 

Task 2 (Flight Test Analysis)

 

Using the data obtained from the data logger (and where necessary, the on board camera), analyse the following, making comparisons to theoretical values where applicable:

 

?             Methodology of the flight test;

?             Atmospheric properties at flight altitude;

?             Distance and time to take-off;

?             Angle and rate of climbs during the take-off phase;

?             Turning performance;

?             Angle and rate of descent during the landing phase;

?             Distance and time during landing to a taxiing speed;

?             Any other areas of interest during the test flight.

 

Appendix 1 details how to extract the data from your flight recording.

 

Task 3 (Stability Analysis)

 

As part of the test flight, some aircraft dynamics have been demonstrated. You are to combine the practical aspects with known theory to discuss aircraft stability.

 

Part A

Investigate the major airframe design features which affect the lateral-directional stability of a typical wing-tail aircraft such as the Eurostar, particularly the effects of adverse yaw. Analytical and mathematical techniques should be used where appropriate, in addition to any specific examples you feel would enhance your response.

 

Part B

Dynamic motions are generally investigated over a period of time. Identify the 3 lateral-directional dynamic motions and the 2 longitudinal dynamic motions and their causes. Hence analyse the events of each of these motions, making reference to key parameters (i.e. altitude, airspeed, direction etc.). Your answer should also cover method of increasing the positive dynamic stability of a typical wing-tail aircraft.

 

Instructions:

 

 

 

 

TASK 1 (A + B)    Introductory performance theory           

                Mathematical analysis of drag polar        

                Use of industry standard software          

                Mathematical analysis, accuracy and discussion of performance parameters (inc. units)

                Graphical analysis (drag, CL/CD)

TASK 2  Methodology and discussion     

                Analysis and comparison of flight test data          

TASK 3 (A + B)    Introductory stability theory      

                Stability Design Factors + Adverse Yaw  

                Aircraft Dynamic Stability             

–             Concluding         

                Technical Report Presentation and Referencing

All sources should be referenced using the Harvard reference system.

Your report should not exceed a word count of 2000 words (excluding references,          appendices and contents).

Note: Task 2 not done and report is 1500 words only