1 Airship fo shizzle
Jon Anderson Team Lead Hours Worked: Team Member Jon Anderson
Agenda 3 Outline: Vehicle selection – Military Decision Making Process (FM 101-5) Airship Design Airship Performance Deployment Enabling technologies Recommendation and conclusion Questions 3Jon Anderson
4 Problem Determine which aero-vehicle or combination of aero- vehicle would be best suited for a mission to Titan. Apply Military Decision Making Process
5 Recommendation A combination helicopter – airship design Helicopter – Primary science mission Collect scientific information Airship – Primary communication mission Relay science information to orbiter/earth
6 Facts Vehicle must be able to land. Vehicle must be able to carry the given science instrument payload. Vehicle must have some means of self propulsion. Only a helicopter-airship combination will be evaluated. Most heavily researched options.
7 Assumptions All designs can survive atmospheric conditions All designs can be packaged into a 3 m diameter aero shell All designs will operate within 0-5 km of the surface
8 Courses of Action Helicopter Airship Tilt-Rotor Airplane/Glider Helicopter/Airship combination
9 Screening Criteria Vehicles must have some basic research done from other sources. Can’t design vehicles from nothing
10 Evaluation Criteria Mass – Lower is better Pre Designed Level – Higher is better Operational Life time – Longer is better Top Speed – Higher is better Redundancy – 0 if not available, 1 if available
11 Weighing Criteria Pre-designed Level – 10% Mass – 25% Operational Life time – 15% Top Speed – 10% Redundancy – 40% Assign 1,2,or 3 with 1 being the best in that category
12 Analysis – COA screened out Tilt rotor Airplane/Glider Lack of information
13 COA - Airship Mass – 490 kg Pre Designed Level - High Operational Life time – 150 Days Top Speed – 3.5 m/s Redundancy - None
14 COA - Helicopter Mass – 290 kg Pre Designed Level - low Operational Life time – 120 Days Top Speed – 4.5 m/s Redundancy - None
15 COA - Combination Mass – UNK – Assume largest Pre Designed Level – Medium Operational Life time – 120 Days Top Speed – 3.5 m/s Redundancy - Yes
16 Information Presentation Took COA Applied weighing criteria Assigned number values based on 1 as the “best” and 3 being the “worst” Tallied findings in a table Example calculation for combination values: Mass - highest mass – scored 3, weight 10%, score =.3 Pre-design level – second highest – scored 2, weight 10%, score =.2
17 Analysis Continued - Airship Mass (10%) Pre-design level (10%) Life time (15%) Speed (15%) Redun. (50%) Total Airship Helicopter Combination Overall Total score – Lower is better Combination is the recommended COA Through research – divided mission of science and communication to save on overall mass.
18 Airship Design Jon Anderson Mission Goal: The primary mission of the airship is to function as a relay between the orbiter and the helicopter. The secondary mission of the airship is to function as a reserve platform capable of carrying out the science mission should the helicopter become inoperable.
19 Design Constraints Jon Anderson Communication payload Extra redundancy – orbiter and helicopter Science payload Power subsystem MMRGT
20 Assumptions Jon Anderson Mass Assumption: Needed initial estimate for mass of hull and structural components Found fraction of weight for non-hull components vs NASA Estimated initial weight Designed airship, calculated final mass Reiterated process with calculated mass
21 Equations Jon Anderson Buoyancy and Volume equations: Shape and Surface Area equations: Sources: 5. Wolfram: The Mathematica Book, Wolfram Media, Inc., Fourth Edition, Gradshteyn/Ryzhik: Table of Integrals, Series and Products, Academic Press, Second Printing, 1981
22 Equations Jon Anderson Drag and Reynolds number equations: Thrust and power available equations:
23 Diagram of Airship Jon Anderson Length13.83 m Width3.45 m Volume34.47 m^3 Ballonet volume8.96 m^3 Fins1x1x.7 m Gondola.7x.7x1.63 m 20% Margins
24 Reynolds # and Drag vs Velocity Jon Anderson
25 Power Required/Available vs Velocity Jon Anderson
26 Inflation time/percent vs Lift Jon Anderson
27 Performance Jon Anderson Mass195 Kg Operational Cruse Velocity2.5 m/s Max Velocity2.98 m/s Min Climb/Descent Rate *50 m/min Range36200 km Service Ceiling5 km Absolute Ceiling40 km Estimated Lifetime *150 days
28 Deployment Jon Anderson Airship inflation immediate Both bayonets and main envelope Changing ballistic coefficient Separate via explosive shearing bolts Immediately max velocity
29 Enabling Technologies Jon Anderson Multi Mission Radioisotope Thermal Generator Complicated – beyond scope of design 5 fold increase in power Lower mass
30 Recommendation and Conclusion Jon Anderson High Altitude Design Detailed data bandwidth analysis Hull/system optimization Experments
31 Questions? Jon Anderson
32 Backup slides - Mass Jon Anderson ComponentMass (kg)Mass after 20% Margin (kg) Subsystem Power2nd Generation MMRTG Battery - 12 A h lithium Turbomachinery Turbine Compressor Piping Electric Motor Alternator Total PropulsionPropeller, axel, case* Total Science InstrumentsHaze and Cloud Partical Detector33.6 Mass Spectrometer1012 Panchromatic Visible Light Imager Total CommunicationX-Band Omni - LGA SDST X-up/X-down X-Band TWTA UHF Transceiver (2) UHF Omni UHF Diplexer (2)11.2 Additional Hardware (switches, cables, etc.)67.2 Total ACDSSun Sensors IMU (2)910.8 Radar Altimeter Antennas for Radar Altimeter Absorber for Radar Altimeter Air Data System with pressure and temperature56 Total2024
33 Backup slides - Mass Jon Anderson C&DHFlight Processor Digital I/O - CAPI Board State of Health and Attitude Control Power Distribution (2) Power Control Mother Board Power Converters (For Integrated Avionics Unit) Chassis Solid State Data Recorder Total StructureAirship Hull Gondola* Tail Section: 4 Fins and attachments* Attitude Control44.8 Helium Mass (Float at 5 km) Inflation tank for Helium* Bayonet fans and eqipment Total ThermalInflight and during operation Total Total Airship Dry Mass Total Aiship Float Mass
34 Backup slides Component Power Required (W) Power Required after 20% Margin (W) Subsystem Power580 W Generated ProplusionPropeller/EngineSee Figure 2 TotalSee Figure 2 BayonetsFans (2)90108 Total90108 Science InstrumentsHaze and Cloud Partical Detector20 Mass Spectrometer28 Panchromatic Visible Light Imager10 Total CommunicationUHF Transceiver74.88 Total
35 Backup slides - Power Jon Anderson ACDS*Sun Sensors 0.56 IMU22.2 Radar Altimeter37.6 Air Data System with pressure and temperature7.72 Total68.08 C&DH*Flight Processor; >200 MIPS, AD750, cPCI11.6 Digital I/O - CAPI Board3.44 State of Health and Attitude Control - SMACI3.44 Power Distribution6.88 Power Control3.44 Power Converters (For Integrated Avionics Unit)13.84 Solid State Data Recorder0.64 Total43.28 Total Power Required without proplusion with all systems operating - Straight and level Total Power Available for Propulsion - Straight and level335.84