The Use of Flight Simulation to Analyze Aircraft Design and Performance Douglas L.Wilson – Chief Test Pilot Abraham Gutierrez – Chief Systems Engineer Anh Huy Nguyen – Chief Flight Engineer Advisor – Basil Philip Sponsor: Dr. Ron O. Stearman

Objectives  Look into the background of two crashes - Mooney Cessna 172H-2000  Conduct Several Test - Flight Simulator (X-Planes) - Real Test (Cessna 172H or similar version)  Perform Test Runs - Weather Conditions - Plane configurations  Determine if Phugoid Mode can be Demonstrate - Mooney Flight Simulator Abraham Gutierrez Anh Huy Nguyen Douglas Wilson

Background  Mooney Rocket Engine modification to the Mooney M20K - Modified engine caused the aircraft to enter a phugoid mode  Cessna 172H - Engine Power - Flap Settings Abraham Gutierrez Anh Huy Nguyen Douglas Wilson

Presentation Outline  Outline -Mooney 305 Crash Report Crash Report Timeline of the crash Timeline of the crash Comparison Comparison 305 Rocket Airplane 305 Rocket Airplane What is Phugoid Mode? What is Phugoid Mode? Phugoid Mode Analysis Phugoid Mode Analysis Future Work Future Work -Cessna 172H Cessna specifications Cessna specifications Performance Performance Weight and Balance Weight and Balance Cessna Crash Cessna Crash NTSB Investigation NTSB Investigation Suggested Causes Suggested Causes - Cessna 172H Flight Testing Flight Testing Data Conversion Data Conversion Preliminary Results Preliminary Results Proposed Flight Test Proposed Flight Test Flight Simulation Flight Simulation Cost Analysis Cost Analysis Time Analysis Time Analysis Acknowledgements Acknowledgements Abraham Gutierrez Anh Huy Nguyen Douglas Wilson

Crash Report  Accident -In May 5, 1998 the Mooney 305 crashed near Bakersfield, California -In the accident the pilot suffer fatal injuries  Investigation (2 Reports) -The (NTSB) report indicated that pilot exceeded the never to exceed velocity which caused flutter: consequently the airplane suffer severe damage in the airframe. -Another (Dr. Stearman) report, indicated that the airplane didn’t exceed the never to exceed velocity but that the flutter was triggered by an overload damage to the horizontal tail brought on by the aircraft maneuvering in an unstable phugoid mode.  Crash Report TimelineComparison 305 Rocket Airplane What is Phugoid Mode? Phugoid Mode Summary Abraham Gutierrez Anh Huy Nguyen Douglas Wilson

Timeline for the 305 Rocket 19000ft ft ft Crash Report  Timeline Comparison 305 Rocket Airplane What is Phugoid Mode? Phugoid Mode Summary Abraham Gutierrez Anh Huy Nguyen Douglas Wilson

Changes Specifications Mooney M20K Mooney 305 Horsepower 210HP 305HP Propeller 2 blades 3 blades Max takeoff weight 2900lbs 3200lbs Max landing weight 2900lbs 3040lbs Empty weight 1860lbs 2068lbs Max. useful load 1040lbs 1132lbs Stall Speed 60kts 61kts Service Ceiling 24000ft 24000ft Max. Level Speed 198kts 240kts Cruise Speed (kts) 188kts 230kts Takeoff over 50ft 1500ft 1200ft obstacle Crash Report Timeline  Comparison 305 Rocket Airplane What is Phugoid Mode? Phugoid Mode AnalysisSummary Abraham Gutierrez Anh Huy Nguyen Douglas Wilson

305 Rocket Airplane  Mooney 305 -The Mooney 305 is a modification of the Mooney M20K. In which 45 percent more horsepower and a new propeller was added to the airframe of the Mooney M20K -The Federal Aviation Administration awarded the certificates  Mooney 305 Autopilot -Insufficient testing -The autopilot was not modify -If a control system fails during a phugoid mode then accident like the on in Bakersfield can occur. Crash Report TimelineComparison  305 Rocket Airplane What is Phugoid Mode? Phugoid Mode AnalysisSummary Abraham Gutierrez Anh Huy Nguyen Douglas Wilson

What is Phugoid Mode  Phugoid Mode -Is simply an oscillatory mode in the aircraft dynamics which last for a long time compared to other aircraft oscillations. For example: δ t Crash Report TimelineComparison 305 Rocket Airplane  What is Phugoid Mode? Phugoid Mode AnalysisSummary Abraham Gutierrez Anh Huy Nguyen Douglas Wilson

Phugoid Analysis  Equation of motion -we are going to use the principle of conservation of energy: 1) T+V=K (T=kinetic energy) and (V=potential 2) State variables or inputs x=(v,v’) 3) External Vertical Force U=F 4) State Matrix Equation x’=Ax+Bu x’ = x + F x’ = x + F -2*g^2/vo^2 0 g/mvo -2*g^2/vo^2 0 g/mvo 5) Output (position,kinetic/potential energy,) Damped or Undamped Crash Report TimelineComparison 305 Rocket Airplane What is Phugoid Mode?  Phugoid Analsis Summary Abraham Gutierrez Anh Huy Nguyen Douglas Wilson

Summary  Mooney M20K -Model of the Mooney 305 in X-plane -Flight Simulator  Matlab code - Matlab program to fix the autopilot of the modified Mooney M20k -Matlab programs to identify the phugoid mode -Matlab program provided for us. Crash Report TimelineComparison 305 Rocket Airplane What is Phugoid Mode? Phugoid Mode  Summary Abraham Gutierrez Anh Huy Nguyen Douglas Wilson

Summary  Damping Stages Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Crash Report TimelineComparison 305 Rocket Airplane What is Phugoid Mode? Phugoid Mode  Summary

Cessna 172H Specifications Specifications Top Speed at Sea Level 138 mph Rate of Climb at Sea Level 645 fpm Service Ceiling 13,100 ft Propeller 76 in Landing Landing Roll 520 ft Total Distance over 50-foot Obstacle 1250 ft Take-off Ground Run 865 ft Total Distance over 50-foot Obstacle 1525 ft Abraham Gutierrez Anh Huy Nguyen Douglas Wilson  Cessna specifications Timeline of Crash Weights and Balances Performance NTSB Investigation Further Investigation Probable Causes

Timeline of the Cessna 172H Crash Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Cessna specifications  Timeline of Crash Weights and Balances Performance NTSB Investigation Further Investigation Probable Causes

Weights and Balances Max Gross Weight 2300 lbs. Empty Weight 1400 lbs. Full Fuel Tanks 252 lbs. Pilot 264 lbs. Front Passenger 251 lbs. Rear Passenger 120 lbs. The aircraft was close to max weight. Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Cessna specifications Timeline of Crash  Weights and Balances Performance NTSB Investigation Further Investigation Probable Causes

Performance Standard atmospheric conditions (Cessna Pilot Handbook) Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Cessna specifications Timeline of Crash Weights and Balances  Performance NTSB Investigation Further Investigation Probable Causes

Cessna NTSB Findings  The airplane was found 300 yards southwest of the end of runway 31  The engine and nose was found aft in the cabin area  Chord-wise crush damage sustained aft to the wing forward spars  Propeller blade bent and scratched  Left door torn from fuselage  Flap actuator was working properly  No mechanical malfunction to engine assembly  Wing flaps were set at 40 degrees (Manufacturer recommended 0 degree settings for take-off) Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Cessna specifications Timeline of Crash Weights and Balances Performance  NTSB Investigation Further Investigation ProbableCauses Probable Causes

Further Investigation  At impact the tachometer was stuck at 1500 RPM  If this was the correct engine output, the aircraft would not be able to maintain a climb attitude. Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Cessna specifications Timeline of Crash Weights and Balances Performance NTSB Investigation  Further Investigation Probable Causes

 Pilot attempted a touch-and- go landing and left the flaps down at 40 degrees  Engine malfunction during take-off that resulted in a partial or total power loss Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Cessna specifications Timeline of Crash Weights and Balances Performance NTSB Investigation Further Investigation  Probable Causes

Flight Testing  Test SP4-E101  February 22, 2004  Georgetown Municipal Airport (KGTU)  Weather Conditions Abraham Gutierrez Anh Huy Nguyen Douglas Wilson  Flight Testing Data Conversion Preliminary Results Proposed Flight Test Flight Simulation Cost Analysis Time Analysis Acknowledgements

Flight Testing  Cessna 739ZY  172 N model  160 HP (O-320 engine)  Tests performed  2 weights  2 altitudes  5 flap settings Abraham Gutierrez Anh Huy Nguyen Douglas Wilson  Flight Testing Data Conversion Preliminary Results Proposed Flight Test Flight Simulation Cost Analysis Time Analysis Acknowledgeme nts

Flight Testing Cessna 739ZY – Weight 1 A/C empty weight tested lbs Fuel Capacity (40 gal) lbs Passengers/gear~400.0 lbs TOTAL TEST WEIGHT ~ lbs Abraham Gutierrez Anh Huy Nguyen Douglas Wilson  Flight Testing Data Conversion Preliminary Results Proposed Flight Test Flight Simulation Cost Analysis Time Analysis Acknowledgements

Flight Testing Abraham Gutierrez Anh Huy Nguyen Douglas Wilson  Flight Testing Data Conversion Preliminary Results Proposed Flight Test Flight Simulation Cost Analysis Time Analysis Acknowledgements

Flight Testing Cessna 739ZY – Weight 2 A/C empty weight tested lbs Fuel (22 gal) lbs Passengers/gear ~615.0 lbs TOTAL TEST WEIGHT ~ lbs Abraham Gutierrez Anh Huy Nguyen Douglas Wilson  Flight Testing Data Conversion Preliminary Results Proposed Flight Test Flight Simulation Cost Analysis Time Analysis Acknowledgements

Flight Testing Abraham Gutierrez Anh Huy Nguyen Douglas Wilson  Flight Testing Data Conversion Preliminary Results Proposed Flight Test Flight Simulation Cost Analysis Time Analysis Acknowledgements

Data conversion Provides for the analysis of the 172 H model Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Flight Testing  Data Conversion Preliminary Results Proposed Flight Test Flight Simulation Cost Analysis Time Analysis Acknowledgements

Preliminary Results 172 H Conversion Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Flight Testing Data Conversion  Preliminary Results Proposed Flight Test Flight Simulation Cost Analysis Time Analysis Acknowledgements

Proposed Flight Test  Cessna 172 E model  O-300 engine  2300 lb gross take-off weight  42 gal max fuel capacity  40 degree flap settings  Cruise prop installed on the A/C Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Flight Testing Data Conversion Preliminary Results  Proposed Flight Test Flight Simulation Cost Analysis Time Analysis Acknowledgements

Flight Simulation  Mooney Simulations  Performed at WRW Laboratories  X-Plane software  Easy to use  Allows for proper data output  Autopilot will be engaged  Monitor output to determine if phugoid mode is present Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Flight Testing Data Conversion Preliminary Results Proposed Flight Test  Flight Simulation Cost Analysis Time Analysis Acknowledgements

Aircraft Modifications ModificationBravo Rocket 305 Horsepower 210 HP 305 HP Propeller 2 blade 3 blade Max Weight 2900 lbs 3200 lbs Empty Weight 1860 lbs 2068 lbs Stall Speed 60 kts 61 kts Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Flight Testing Data Conversion Preliminary Results Proposed Flight Test  Flight Simulation Cost Analysis Time Analysis Acknowledgements

Flight Simulation  Presently have 5 test aircraft  172 SP  172 SP – modified for 40 degrees of flaps  172 H – A/C in accident  172 N – A/C in actual flight test  172 E – Proposed test A/C Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Flight Testing Data Conversion Preliminary Results Proposed Flight Test  Flight Simulation Cost Analysis Time Analysis Acknowledgements

Aircraft Modifications PART 172 SP (N463QB) 172 SP (N463QC) 172 H (N463QD) 172 N (N463QE) Flaps 30 deg 40 deg Horsepower 180 hp 145 hp 160 hp Fuel System Fuel Injected CarburetorCarburetor Flight Testing Data Conversion Preliminary Results Proposed Flight Test  Flight Simulation Cost Analysis Time Analysis Acknowledgements Abraham Gutierrez Anh Huy Nguyen Douglas Wilson

Flight Simulation  Cessna Testing – Stage 1  Verification flights  Repeat previous flight tests  Performance tests to compare to manufacturer and actual flight data  MOST IMPORTANT PHASE OF TESTING! Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Flight Testing Data Conversion Preliminary Results Proposed Flight Test  Flight Simulation Cost Analysis Time Analysis Acknowledgements

Flight Simulation  Cessna Testing – Stage 2  Attempt to recreate the accident  Take-offs with 40 degrees of flaps at desired weight  Takeoff with engine failure at ~300 feet AGL Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Flight Testing Data Conversion Preliminary Results Proposed Flight Test  Flight Simulation Cost Analysis Time Analysis Acknowledgements

Cost Analysis  Currently 4.2 hours of real flight testing  Aircraft rental: $79/hr - $  Instructor fee: $35/hr - $  Total current cost: $  Projected 5 hours of additional real flight testing  Total expenses ~ $1000 Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Flight Testing Data Conversion Preliminary Results Proposed Flight Test Flight Simulation  Cost Analysis Time Analysis Acknowledgements

 Phase 1 – Completed  Background investigations into both accidents  Phugoid mode analysis  A/C modifications made in flight simulators  Phase 2A – Completion projected March 5  Actual flight testing of Cessna A/C  Added to validate flight simulator data Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Flight Testing Data Conversion Preliminary Results Proposed Flight Test Flight Simulation Cost Analysis  Time Analysis Acknowledgements

Time Analysis  Phase 2B – Completion projected April 10  Flight Simulator Testing  Validation phase – completion projected March 20  Accident Recreation  Cessna 172 H  Mooney Rocket  Phase 3 – Completion projected May 5  Analysis of flight data  Final reports and recommendations Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Flight Testing Data Conversion Preliminary Results Proposed Flight Test Flight Simulation Cost Analysis  Time Analysis Acknowledgements

Acknowledgments  Wright Aviation in Georgetown, TX  Bill Eldredge and staff  Alan Weaver – Flight Instructor  Dr. Ron O. Stearman  Basil Philip  Marcus Kruger  Joshua Foxworth Abraham Gutierrez Anh Huy Nguyen Douglas Wilson Flight Testing Data Conversion Preliminary Results Proposed Flight Test Flight Simulation Cost Analysis Time Analysis  Acknowledgements

Summary  Mooney 305  Bakersfield, CA accident  Phugoid Mode  Cessna 172H  Falcon Field Accident  Flap settings and Engine Concerns  Flight Testing  Real Flight tests  X-Plane Simulator testing Abraham Gutierrez Anh Huy Nguyen Douglas Wilson