AIAA Student Design Competition Homeland Defense Interceptor: Gavial Virginia Polytechnic Institute VersaCorp AeroSpace ... May 12, 2006 1 Executive Summary In response to the Request for Proposal [1] from the AIAA Foundation Undergraduate Team Aircraft Design Competition, VersaCorp Aerospace from Virginia Polytechnic Institute and State University proudly presents Gavial, a next generation Unmanned Combat Aerial Vehicle, Homeland Defense Interceptor (UCAV- HDI). The Gavial meets the design mission requirements of providing superior operational capability while maximizing cost-effectiveness in all facets of the design. The Gavial is designed primarily for supersonic performance. This led to the use of a highly swept cranked arrow wing with a blended fuselage. Primary control is provided by canards and a single vertical tail. The Gavial also utilizes a single engine in the 35,000 lb thrust class. Missiles are stored externally on under-wing hard-points, and rail launched. The flyaway cost of the Gavial is ˜$15,000,000, with half˜ of that being for materials and systems. The Gavial is capable of performing three distinct missions, each contributing significantly to the aircraft’s overall mission of ensuring homeland security. The streamlined fuselage is equipped with the M61-A1 Vulcan 20mm Gatling rotary gun which is driven by the aircraft’s hydraulic system and has a maximum rate of fire of up to 7,200 shots per minute (SPM), providing the Gavial with excellent lethality during dog-fighting and pinpoint attacks. The wing undercarriage is capable of carrying a maximum of four AIM-120 advanced medium-range air-to-air missile (AMRAAM), four AIM-9 Sidewinder missiles, or a combination of two AIM- 120 missiles and up to two AIM-9s. Such arsenal versatility optimizes the Gavial’s performance in the RFP specified Defensive Counter-Air Patrol (DCAP), Intercept/Escort and Point Defense Intercept missions. The option of mounting three 660 gallon exterior fuel tanks provides the capability of fulfilling the DCAP missions four hour loiter requirement. As a supersonic performer, the Gavial is designed to minimize drag and maximize maneuverability at the design altitude of 35,000ft, out-performing many operational features of modern fighters. The inclusion of the most advanced radar and UCAV communications systems, including a portable next-generation ground station, maximizes mission effectiveness while simultaneously decreasing the overall cost of the aircraft and completely eliminating pilot risk. This highly survivable and versatile aircraft highly exceeds many of the RFP requirements with an Initial Operational Capability (IOC) date of 2020 and a flyaway cost of $15 million. i ii Summary of Requirements Criterion Requirement DCAP I/E Intercept Mission Radius 200 nm N/A Met CAP Endurance at 300 nm Radius 4 Hrs Met N/A Performance at Maneuver Weight Maximum Mach Number at 35,000 ft 2.2 Not Met 1.7 Met 2.2 Min Sustained Load Factor -at Maximum Thrust 5 g´s Met 9 g’s Met 9 g’s Max Instantaneous Turn Rate at 35,000 ft 18.0 ◦/s Met 21.2 ◦/s Met 21.2 ◦/s 1-g Specific Excess Power -Military Thrust 0.9M/Sea Level 200 ft/s Met 1401 ft/s Met 1500 ft/s 0.9M/15,000 ft 50 ft/s Met 983 ft/s Met 1000 ft/s 1-g Specific Excess Power -Maximum Thrust 0.9M/Sea Level 700 ft/s Met 896 ft/s Met 1053 ft/s 0.9M/15,000 ft 400 ft/s Met 468 ft/s Met 603 ft/s 5-g Specific Excess Power -Maximum Thrust 0.9M/Sea Level 300ft/s Met 354 ft/s Met 496 ft/s 0.9M/15,000 ft 50 ft/s Met 103 ft/s Met 215 ft/s iii Contents 1 RFP Analysis 1 1.1 Missions . 1 1.1.1 DCAP Mission . 1 1.1.2 PDI Mission . 2 1.1.3 I/E Mission . 2 1.2 Stability and Control Requirements . 3 1.3 Performance Requirements . 3 1.4 Equipment . 4 1.4.1 Engine . 4 1.4.2 Government Furnished Equipment . 4 2 Survey of Existing Aircraft 5 3 Initial Sizing 7 3.1 Wing Loading and Thrust to Weight Ratio . 7 3.2 Fuel Weight Estimation . 10 4 Conceptual Design 12 5 Configuration Description 18 6 Operational Concept 20 6.1 Manned Vs Unmanned . 20 6.2 Threat Identification, Threat Tracking, Target Verification, Kill Verification, Collision Avoidance 21 6.3 Weapons Integration . 22 6.4 Loss of Vehicle Command and/or Control . 22 6.5 Handling of Enemy Countermeasures . 22 6.6 Aircraft Launch and Recovery Scheme . 23 6.7 Items/Levels of Redundancy Required . 23 6.8 Benefits/Limitations . 23 iv 7 Ground Control Station 24 7.1 Design Objectives . 24 7.2 The Command Chair . 24 7.3 Helmet-mounted Heads Up Display (HUD) Screen . 25 7.4 Vehicle Management System (VMS) . 27 7.5 Final Layout and Platform Assembly . 29 8 Aerodynamics 31 8.1 Wing Planform . 31 8.2 Airfoil Selection . 31 8.3 High-Lift Devices . 35 8.4 Drag . 35 9 Stability and Balancing Scheme 42 9.1 Longitudinal Control . 42 9.2 Control Surfaces . 42 9.3 Canard Sizing . 43 9.4 Control Authority . 44 10 Vehicle Performance 48 11 Propulsion Design 53 11.1 Single vs Multi Engine . 54 11.2 Engine Scaling . 54 11.3 Inlet Design . 55 11.4 Shock Ramps . 56 11.5 Nozzle . 58 12 Structural Design 59 12.1 Materials Selection . 59 12.2 Fuselage Structure . 60 12.3 Wing Structure . 61 12.4 Canard and Tail Structure . 63 12.5 Landing Gear . 63 12.6 Structural Limits . 65 v 13 Weapons/Fire Control System 67 13.1 Weapons . 67 13.2 Wide Angle Cameras . 68 13.3 FLIR . 69 13.4 Radar . 69 14 Internal Systems 70 14.1 General Layout . 70 14.2 Cooling of the Avionics . 73 15 Fuel and Electrical System 74 15.1 Fuel System . 74 15.2 Electrical System . 75 16 Servicing Plan 76 16.1 Forward Avionics Access . 76 16.2 Aft Access . 76 17 Weight Parameters 79 17.1 Takeoff Gross Weight . 79 17.2 Center of Gravity . 79 17.3 Weight and Balance Analysis . 80 18 Cost Estimation 84 vi List of Figures 1.1 Defensive Counter Air Patrol Mission Schematic . 1 1.2 Point Defense Intercept Mission Schematic . 2 1.3 Intercept Escort Mission Schematic . 3 3.1 Sizing Chart for Conceptual Design . 9 4.1 Configuration Flow Chart . 12 4.2 Variable Geometry Concept . 13 4.3 Arrow Wing Concept . 14 4.4 Conventional Wing Concept . 15 4.5 Multiple Lifting Surface Concept . 16 4.6 Drag vs Sweep Angle Comparison . 17 5.1 Gavial Interceptor Configuration . 18 6.1 Operation Control Concept . ..