Jay Carter, Founder &

CARTERAVIATION TECHNOLOGIES An Aerospace Research & Development Company Jay Carter, Founder & CEO CAFE Electric Aircraft Symposium July 23rd, 2017 <a href="/goto?url=http://www.CarterCopters.com" target="_blank">www.CarterCopters.com </a>©W20i1c5 ChAiRtTEaR AFVaIATlIlOsN,TTECeHNxOaLOsGIES, LLC 1SR/C is a trademark of Carter Aviation Technologies, LLC A History of Innovation Built first gyros while still in college with father’s guidance Led to job with Bell Research & Development Steam car built by Jay and his father First car to meet original 1977 emission standards Could make a cold startup & then drive away in less than 30 seconds Founded Carter Wind Energy in 1976 Installed wind turbines from Hawaii to United Kingdom to 300 miles north of the Arctic Circle One of only two U.S. manufacturers to survive the mid ‘80s industry decline ©2015 CARTER AVIATION TECHNOLOGIES, LLC 2SR/C™ Technology Progression 2013-2014 DARPA TERN Won contract over 5 majors 2009 License Agreement with AAI, Multiple Military Concepts 2017 2011 2nd Gen First Flight Later Demonstrated Find a Manufacturing Partner and Begin Commercial Development L/D of 12+ 2005 1st Gen L/D of 7.0 1998 1st Gen First flight 1994 - 1997 Analysis & Component Testing 22 years, 22 patents + 5 pending 11 key technical challenges overcome Proven technology with real flight test 1994 Company founded ©2015 CARTER AVIATION TECHNOLOGIES, LLC 3SR/C™ Technology Progression Quiet Jump Takeoff & Flyover at 600 ft agl Video also available on YouTube: <a href="/goto?url=https://www.youtube.com/watch?v=_VxOC7xtfRM" target="_blank">https://www.youtube.com/watch?v=_VxOC7xtfRM </a>©2015 CARTER AVIATION TECHNOLOGIES, LLC 4SR/C vs. Fixed Wing • SR/C rotor very low drag by being slowed Profile HP vs. Rotor RPM, PAV Rotor Drag per WADC TR 55-410: @ 250 kts @ SL 3 1 4.62 0 CD A R 600 500 400 300 200 100 0b80 HP  O550 299 HPo - Full HPo - Rot Only <ul style="display: flex;"><li style="flex:1">155 </li><li style="flex:1">54 </li></ul>5.7 <ul style="display: flex;"><li style="flex:1">0</li><li style="flex:1">100 </li><li style="flex:1">200 </li><li style="flex:1">300 </li><li style="flex:1">400 </li></ul>Rotor RPM • SR/C wing very small because rotor supports aircraft at low speeds – wing can be sized for cruise • Fixed-wing wing must be sized for low speed/landing • SR/C slowed rotor & small wing equivalent to fixed-wing’s larger wing ©2015 CARTER AVIATION TECHNOLOGIES, LLC 5SR/C Electric Air Taxi Ø34’ <ul style="display: flex;"><li style="flex:1">54” Cabin Width </li><li style="flex:1">36’ </li></ul>©2015 CARTER AVIATION TECHNOLOGIES, LLC 6SR/C Electric Air Taxi– Features Slowed rotor enables 10’ diameter scimitar tail prop rotates to provide counter torque for hover or thrust for forward flight High inertia, low disc loaded rotor acts as built-in parachute, but safer because it works at any altitude / Lightweight, low profile, streamlined tilting hub greatly reduces drag. No spindle, spindle high speed forward flight, low drag, low tip speed/noise, no retreating blade stall speed, and provides directional control housing, bearings or lead-lag hinges Tall, soft mast isolates airframe from rotor vibration for fixed-wing smoothness Tilting mast controls aircraft pitch at low speeds & rotor rpm for high cruise efficiency at high speeds Mechanical flight control linkages to optional pilot in parallel with actuators for true redundancy Extreme energy absorbing fail safe landing gear up to 30 ft/s improves landing safety Simple, light, structurally efficient wing with no need for high lift devices High aspect ratio wing with area optimized for cruise efficiency Battery pack in nose to balance tail weight ©2015 CARTER AVIATION TECHNOLOGIES, LLC 7Performance Parameters Drag coefficients based on actual achieved data, not expected improvements 3200 lb empty weight with batteries 4000 lb max gross weight (800 lb max payload) 300 W-hr/kg battery energy density Assumed margin for 0.5 Empty Weight Fraction at 600 ft/s tip speed Mission: 30 sec HOGE for takeoff, Climb at Vy to 5k ft, Cruise at 175 mph, Descend at Vy, 2 min HOGE at landing (no reserve) Empty Wt (w/o batteries) vs. Rotor Hover Tip Speed Range at 175 mph vs. Payload for Various Hover Tip Speeds 2250 2200 2150 2100 2050 2000 1950 200 180 160 140 120 100 80 2213 lbs 159 miles D=46 miles 113 miles D=213 lbs 600 ft/s 550 ft/s 500 ft/s 450 ft/s 60 40 2000 lbs 20 0<ul style="display: flex;"><li style="flex:1">400 </li><li style="flex:1">450 </li><li style="flex:1">500 </li><li style="flex:1">550 </li><li style="flex:1">600 </li><li style="flex:1">650 </li><li style="flex:1">700 </li><li style="flex:1">0</li><li style="flex:1">200 </li><li style="flex:1">400 </li><li style="flex:1">600 </li><li style="flex:1">800 </li><li style="flex:1">1000 </li></ul><ul style="display: flex;"><li style="flex:1">Rotor Hover Tip Speed, ft/s </li><li style="flex:1">Payload, lbs </li></ul>Note: 150 mph cruise will extend range by ~10% at 800 lb payload <ul style="display: flex;"><li style="flex:1">Figure 1 </li><li style="flex:1">Figure 2 </li></ul>©2015 CARTER AVIATION TECHNOLOGIES, LLC 8Air Taxi Concept Comparison • Compared three different configurations • SR/C • Hex Tilt Rotor • ‘T’ Tilt Rotor • Used common assumptions and methods for all three concepts • Based drag coefficients and parameters on measured flight data from PAV SR/C Carter PAV L/D vs. IAS 14 12 10 8Hex Tilt Rotor Meas'd Model 6420<ul style="display: flex;"><li style="flex:1">0</li><li style="flex:1">50 </li><li style="flex:1">100 </li><li style="flex:1">150 </li><li style="flex:1">200 </li><li style="flex:1">250 </li></ul>IAS, mph Actual Measured Flight Data Note: Data scatter mostly attributable to gathering data when developing rotor rpm / mast control algorithms and varying rotor rpm considerably ‘T’ Tilt Rotor ©2015 CARTER AVIATION TECHNOLOGIES, LLC 9Analysis Methods & Assumptions <ul style="display: flex;"><li style="flex:1">Parameter </li><li style="flex:1">Assumptions </li></ul><ul style="display: flex;"><li style="flex:1">Gross Weight </li><li style="flex:1">4000 lbs </li></ul>200 lbs per person 4 people max Pilot/Pax Weight <ul style="display: flex;"><li style="flex:1">Empty Weight </li><li style="flex:1">Calc’d with same method for all – modified Raymer </li></ul><ul style="display: flex;"><li style="flex:1">Battery & Drive Efficiency </li><li style="flex:1">0.92 </li></ul>80% (top 10% unuseable with rapid charge, bottom 10% unuseable to avoid current spike) Useable Battery Capacity Scaled Linearly with Max Continuous Power <ul style="display: flex;"><li style="flex:1">0.4 lb/HP </li><li style="flex:1">Motor + Inverter Weight </li></ul>Assumed motor could be overloaded 1.87x for 30 sec for OEI Limited current to 40 amp per wire, running multiple wires per leg to reach full current required. Per N.E.C., used AWG-10 with Class C Insulator Wiring Weight Used same coefficients on all concepts & appropriately scaled misc drags as derived from calibrating model to actual flight data from PAV Drag Coefficients Hover Typical Mission Hover Out of Ground Effect (HOGE) at 6k ft with 1.1x margin 30 sec hover, climb, cruise, descent, 30 sec hover 120 sec hover, climb, cruise, descent, 120 sec hover +Reserve: 120 sec hover, 2nm divert, 120 sed hover Planning Mission ©2015 CARTER AVIATION TECHNOLOGIES, LLC 10 Common Footprint • Footprint driven by interface with vertiports • If certain size footprint can be justified, justification is applicable to all technologies • Single Rotor SR/C & Hex Tilt Rotor have similar disc loadings • ‘T’ tilt rotor has very high disc loading 39 ft ‘T’ TR Hex TR SR/C Rotor Area, ft² Disc Loading, lb/ft² Total Hover HP 30 sec OEI HP Cruise HP at 175 mph 144.9 27.6 774.0 1869.6 467.8 240 240 791.5 5.1 368.4 907.9 4.4 424.0 N/A 207 <ul style="display: flex;"><li style="flex:1">Total Installed Cont HP 1099.2 390.1 </li><li style="flex:1">612.8 </li></ul>•••‘T’ TR Rotor Area only includes 4 lifting rotors (tails rotors for trim control only) SR/C Total Hover HP includes tail rotor power to counter torque All Hover HPs include 10% lift margin ©2015 CARTER AVIATION TECHNOLOGIES, LLC 11 Comparison Preliminary Results • ‘T’ Tilt Rotor has very high HP required due to disk loading – higher empty weight for installed HP • SR/C has better L/D @ 175 mph due to smaller wings & less wetted area from prop spinners, fuselage, & no LG sponsons <ul style="display: flex;"><li style="flex:1">Empty Weight vs. Width </li><li style="flex:1">Range vs. Payload </li></ul>2,100 2,050 2,000 1,950 1,900 1,850 1,800 1,750 1,700 180 160 140 120 100 80 60 40 20 0 SR/C - 40 ft SR/C - 37 ft SR/C - 34 ft Hex TR - 40 ft Hex TR - 37 ft Hex TR - 34 ft 'T' TR - 40 ft 'T' TR - 37 ft 'T' TR - 34 ft SR/C Hex TR T TR <ul style="display: flex;"><li style="flex:1">32 </li><li style="flex:1">34 </li><li style="flex:1">36 </li><li style="flex:1">38 </li><li style="flex:1">40 </li><li style="flex:1">42 </li><li style="flex:1">0</li><li style="flex:1">200 </li><li style="flex:1">400 </li><li style="flex:1">600 </li><li style="flex:1">800 </li><li style="flex:1">1000 </li></ul><ul style="display: flex;"><li style="flex:1">Overall Width, ft </li><li style="flex:1">Payload, lbs </li></ul><ul style="display: flex;"><li style="flex:1">L/D vs. Airspeed </li><li style="flex:1">Mileage vs. Payload </li></ul>16 14 12 10 81.4 1.2 1 SR/C - 40 ft SR/C - 40 ft SR/C - 37 ft SR/C - 34 ft Hex TR - 40 ft Hex TR - 37 ft Hex TR - 34 ft 'T' TR - 40 ft 'T' TR - 37 ft 'T' TR - 34 ft SR/C - 37 ft SR/C - 34 ft Hex TR - 40 ft Hex TR - 37 ft Hex TR - 34 ft 'T' TR - 40 ft 'T' TR - 37 ft 'T' TR - 34 ft 0.8 0.6 0.4 0.2 06420<ul style="display: flex;"><li style="flex:1">0</li><li style="flex:1">50 </li><li style="flex:1">100 </li></ul>True Airspeed, mph <ul style="display: flex;"><li style="flex:1">150 </li><li style="flex:1">200 </li></ul><ul style="display: flex;"><li style="flex:1">0</li><li style="flex:1">200 </li><li style="flex:1">400 </li><li style="flex:1">600 </li><li style="flex:1">800 </li><li style="flex:1">1000 </li></ul>Payload, lbs ©2015 CARTER AVIATION TECHNOLOGIES, LLC 12 Comparison Preliminary Results • SR/C has farthest range with least energy used in typical mission, due to better L/D at 175 mph • ‘T’ Tilt rotor has low useable energy because of high empty weight fraction. Has low percentage of energy available for cruise because of high HOGE power requirements for planning / reserve. Useable Energy Budget, 800 lb payload, 34' width 180 160 140 R3. Reserve 2 min HOGE 120 100 80 60 40 20 0R2. 2 nm reserve at best endurance R1. Reserve 2 min HOGE Reserve P1. 90 sec + 90 sec add'l HOGE for planning 5. 30 sec HOGE Add’l HOGE for Planning 4. Descend to Ldg Altitude 3. Cruise at 5000 at 175 mph 2. Climb at Max ROC to Cruise Alt 1. 30 sec HOGE Typical Mission <ul style="display: flex;"><li style="flex:1">SR/C (123 mile) </li><li style="flex:1">Hex TR (110 mile) </li><li style="flex:1">'T' TR (49 mile) </li></ul>©2015 CARTER AVIATION TECHNOLOGIES, LLC 13 Extreme Energy Absorbing Landing Gear • Extreme energy absorbing – 24” stroke for Carter Smart Strut descent rates up to 24 ft/s at touchdown • Responds to impact speed for near constant Belleville Stackup to control valve to keep pressure on piston near constant based on impact deceleration across full throw of gear • No rebound – no bouncing • Proven technology – used on all Carter Air Over Hydraulic for Energy prototypes • Lightweight due to efficient energy absorption Absorption velocity PAV Single Strut Design Energy Absorbing Cylinder Automatic Metering Valve Hydraulic Pressure in Lower Cylinder for Gear Retract Main Gear Trailing Arm Torque Tube ©2015 CARTER AVIATION TECHNOLOGIES, LLC 14 Energy Absorbing Landing Gear Video Video also available on YouTube: <a href="/goto?url=https://www.youtube.com/watch?v=MntCeJRl2YE" target="_blank">https://www.youtube.com/watch?v=MntCeJRl2YE </a>©2015 CARTER AVIATION TECHNOLOGIES, LLC 15 Energy Absorbing Landing Gear Note near constant pressure over full stroke 100 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5Piston position (8.44" max) Valve position (.5" max) Pressure Top (3000 psi max) Pressure Bottom (3000 psi max) 0<ul style="display: flex;"><li style="flex:1">0</li><li style="flex:1">0.5 </li><li style="flex:1">1</li><li style="flex:1">1.5 </li><li style="flex:1">2</li></ul>Time (s) Data from drop test shown in previous slide ©2015 CARTER AVIATION TECHNOLOGIES, LLC 16 Carter Scimitar Propeller • Highly swept to reduce apparent Mach number – Allows higher CL’s, faster tip speeds, & thicker airfoils – Swept tip reduces noise • Twist a compromise between high speed cruise & static/climb • Lightweight composites 1/2 to 1/3 the weight of conventional designs • 100” diameter prop shown weighs 42 lb • Tested at Mach 1 for cumulative 10 minutes • Wide chord – blade not stalled • Spinner nearly flat at prop root – Reduces decreasing pressure gradient, keeping good airflow on prop root • Cruise efficiencies of 90+% • Static/climb efficiencies on order of 30% better than conventional designs ©2015 CARTER AVIATION TECHNOLOGIES, LLC 17 Scimitar Propeller – Bearingless Design • Pitch change accomplished by twisting the spar • Eliminates spindle, spindle housing, and bearings used on conventional propeller – simple & lightweight • Similar design used on Carter rotors which further eliminates lead/lag and coning hinges Video also available on YouTube: <a href="/goto?url=https://www.youtube.com/watch?v=scrXVfwJ7hY" target="_blank">https://www.youtube.com/watch?v=scrXVfwJ7hY </a>©2015 CARTER AVIATION TECHNOLOGIES, LLC 18 CARTERAVIATION TECHNOLOGIES An Aerospace Research & Development Company Jay Carter, Founder & CEO CAFE Electric Aircraft Symposium July 23rd, 2017 <a href="/goto?url=http://www.CarterCopters.com" target="_blank">www.CarterCopters.com </a>©W20i1c5 ChAiRtTEaR AFVaIATlIlOsN,TTECeHNxOaLOsGIES, LLC SR/C is a trademark of Carter Aviation Technologies, L1LC9 Backup Slides ©2015 CARTER AVIATION TECHNOLOGIES, LLC 20 Mission Definition • Using same typical & planning missions as McDonald and German* • Typical mission for operating cost only requires 30 sec hover for T.O. & landing • Worst case mission for planning (i.e. charge required before taking off to fly a given mission) requires 120 sec T.O. & landing for given mission + 120 sec T.O. & landing for reserve + 2 nm reserve cruise • For sizing, assuming 4 min continuous hover *McDonald, R. A., German, B.J., “eVTOL Energy Needs for Uber Elevate,” Uber Elevate Summit, Dallas, TX, April 2017. ©2015 CARTER AVIATION TECHNOLOGIES, LLC 21 Cruise Performance Model • Analysis conducted with Carter’s proprietary cruise analysis model • For SR/C, developed mainly for cruise when rotor is unloaded • Model calibrated to measured flight data for PAV. Inputs were scaled Carter PAV L/D vs. IAS appropriately for these concepts. 14 12 10 8• Had to estimate drag contributions from different elements, since the aircraft is only instrumented to measure overall thrust* • Interference & separation drags can account for up to ~1/2 of total aircraft drag, and must be accounted for to allow accurate L/D prediction (based on flight test experience by Carter and Bell Helicopter / Ken Wernicke) Meas'd Model 6420<ul style="display: flex;"><li style="flex:1">0</li><li style="flex:1">50 </li><li style="flex:1">100 </li><li style="flex:1">150 </li><li style="flex:1">200 </li><li style="flex:1">250 </li></ul>IAS, mph • Air taxi analysis breaks flight into short segments, incorporating climb, descent, and reserves Note: Data scatter mostly attributable to gathering data when developing rotor rpm / mast control algorithms and varying rotor rpm considerably * Overall drag is calculated based on thrust adjusted for rate of climb/descent – report with methods is available ©2015 CARTER AVIATION TECHNOLOGIES, LLC 22 Battery Assumptions • Using same rationale as McDonald and German* for useable battery capacity • Top 10% & Bottom 10% of capacity inaccessible • 80% capacity accessible DOD = Depth of Discharge • Ignoring internal resistance losses for this analysis Ignored for this analysis *McDonald, R. A., German, B.J., “eVTOL Energy Needs for Uber Elevate,” Uber Elevate Summit, Dallas, TX, April 2017. ©2015 CARTER AVIATION TECHNOLOGIES, LLC 23 Motor Overload Capacity • Overload capacity very dependent on specific motor – see examples below from various sources (only shown to illustrate behavior – these aren’t the motors being used) • Model with a simple empirical curve that mimics those trends, where C is a constant 퐶 푇푖푚푒 = 2퐼 − 1 퐼푟푎푡ꢀ푑 • Based on text in ‘Uber Elevate’, assume a motor that can be overloaded 1.5x for 90 seconds (paper stated 1–2 min). Matching above formula to that data point, C = 22.5 t, sec I/Ir 15 2.22 Thermal Limit assuming 90 sec @ 1.5x 120 100 80 60 40 20 030 1.87 45 1.71 60 1.61 90 1.50 120 1.43 240 1.31 480 1.22 1.87x for 30 sec OEI 1.31x for 4 min HOGE <ul style="display: flex;"><li style="flex:1">1</li><li style="flex:1">1.5 </li><li style="flex:1">2</li><li style="flex:1">2.5 </li><li style="flex:1">3</li></ul>I / I_rated Data from manufacturer needed to improve this estimate ©2015 CARTER AVIATION TECHNOLOGIES, LLC 24 Empty Weight Estimation • Weight estimate for all concepts used same methodology • Structures & Equipment Groups based on method in Chapter 15 of Raymer, Daniel P: Aircraft Design: A Conceptual Approach • Structures weights multiplied by 0.50 to reflect gains from carbon-

Jay Carter, Founder &

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