Joint Heavy Lift(JHL)Joint Heavy Lift(JHL)-JSF Lift Fan Derivative-JSF Lift Fan Derivative

Ryan Aaron

Chris Bradshaw

Jesus Claudio

Romen Cross

Kevin Ferguson

Juan Gutierrez

Phil Lines

Scope of PresentationScope of Presentation

Mission Overview Design Characteristics Initial Engine Design Final Engine and Fan Design Driveshaft/Gearbox Design Internal Design Analysis/Methodology Areas of Emphasis

Mission ProfileMission Profile

Mission ProfileMission Profile

L o n g R a n g e H e a v y L i f t A i r c r a f t M i s s i o n P r o fi l e

O b j e c t i v e

1 0 0 n m 2 0 0 n m

0 . 5 h r h o l d i n g e a c h w a y

0 . 4 h r o n d e c k a t o b j e c t i v e

+ 0 . 4 h r f u e l r e s e r v e

1 m i n H O G E S L S t d D a y e a c h w a y

Long Range, Heavy Lift AircraftLong Range, Heavy Lift Aircraft

Key requirements:

– 300 nm radius of action

– Payload: 37,500 lb

– Capability to carry vehicles like LAV, MTVR, or HEMAT (internal or external)

– Capable of 15 minute cargo on load or off load using only aircrew

– Shipboard compatible

– Desired speed in excess of 200 kts

AssumptionsAssumptions Airframe

– C-130J-30 Fuselage Powerplant

– 60,000 lbs. Max Thrust per Lift Fan• 40,000 – 45,000 (std hot day) shp

– 15,000 lbs. Max Thrust per engine (Hover)– Unknown Max thrust available at cruise

• 15,000 lbs thrust required for 0.7 Mach cruise speed

Technology– 2 Lift Fans– High Shaft HP Engines– Current C-17 Cargo Hold Technology

Design Design CharacteristicsCharacteristics

SketchSketch

Aircraft DimensionsAircraft Dimensions

Length 113 ftSpan 95.4 ftHeight 32.25 ft Wing Area 1805 sq ftTail Area Horizontal 520 sq ft Vertical 186 sq ft

SketchSketch

Spot Factor 1.23 x CH53E•1.5 x CH53E (Objective)•2.0 x CH53E (Threshold)

Initial Initial Engine Engine Design Design

Analysis Analysis Procedure/MethodologyProcedure/Methodology

Initial Engine Calculations/Sizing Engine Performance Mission Thrust Requirements Weight Weight and Balance Calculation Mission Comparison

Engine Engine Calculations/SizingCalculations/Sizing

Used Aircraft Engine Design written by Jack Mattingly for engine sizing requirements to calculate Thrust Req., Wing Area, and Fuel Req.

With Thrust req., used GASTURB to estimate engine performance parameters (TSFC)

Engine performance parameters were then plugged back into MATLAB program to finalize weight, wing area, fuel load, and thrust req.

Engine PerformanceEngine Performance

15,000 lbs Thrust for Vertical T/O 6,000 lbs Thrust for Mach 0.7 Cruise 7,500 lbs Thrust for Mach 0.54 Ingress 50,000 shp Required (losses and accessories)

15,000 lbs

JHL Propulsion System

60,000 lbs60,000 lbs

15,000 lbs

Mission Thrust Mission Thrust RequirementsRequirements

MISSION PARAMETER THRUST REQUIRED(lbs)

Takeoff Hover* 155,059 Acceleration & Climb** 59,429 Cruise Outbound 11,891 Ingress*** 43,743 LZ Landing* 143,256 LZ Takeoff* 96,841 Climb & Acceleration** 37,336 Cruise Inbound 11,885 Loiter 5,004 Final Landing* 87,016

– * Denotes Lift-Fans Operating at 100%– ** Denotes Lift-Fans Operating at 40%– *** Denotes Lift-Fans Operating at 25%

Overall WeightOverall Weight

Takeoff Weight– 136,027 lbs.

Fuel– 21,750 lbs.

Payload (w/ crew)– 38,300 lbs.

Empty Weight– 76,777 lbs.

Weight & Balance Calc.Weight & Balance Calc.Component Weight (lbs)Wt. FractionStation (ft)Moment Lift Station Moment

Wings 12,471 9.17% 37.55 468293.9Tail 3,200 2.35% 106 339148.2 112.9 total lengthBody 18,029 13.25% 56 1009609Engine Nacelles (2) & Prop. Sys. 12,979 9.54% 110 1427711 30000 114 3420000Main Landing Gears 4,580 3.37% 64 293120 23%Front Landing Gear 714 0.52% 11 7854 28565.73Mainline Drive Shaft (2) 1,370 1.01% 75 102750Lift Fans (2) 2,000 1.47% 37.55 75100 100000 37.55 3755000MGB 2,500 1.84% 37.55 93875 77% 7175000Fan drive shafts (2) 560 0.41% 37.55 21028 104636.4 55.19231 Center of Thrust

APU 671 0.49% 37.55 25196.05Hydraulics 725 0.53% 100 72525.03 130000Instruments 276 0.20% 7 1929.175Electrical 3,088 2.27% 63 194544 Weight SavingsAvionics 3,629 2.67% 75 272175 **Fiber optic cable 15% less electrical/electronicsFurnishings/Handling 5,416 3.98% 58 314128 **Composite Wing 15% less wingAir Conditioning & Anti-Ice 2,721 2.00% 24 65304 15% less fuselageCockpit Controls 949 0.70% 7.5 7116.024 Automated Handling50% less handlingPilot 200 0.15% 8 1600Copilot 200 0.15% 7.5 1500Loadmaster 200 0.15% 20 4000Aircrewman 200 0.15% 20 4000 Calculated WeightLuggage 100 0.07% 20 2000Cargo 37,500 27.57% 60 2250000 Estimated WeightFuel (left) 8,500 6.25% 37.55 319175Fuel (right) 8,500 6.25% 37.55 319175 Average Weight AnalysisFuel (center) 4,750 3.49% 60 285000

136,027 Total 7509563Empty weight 76,777 55.20629 cg Location

ZFW 108,250

Cargo Bay Design EnvelopeCargo Bay Design Envelope

Standard C-130J-30 fuselage utilized Height accomodates for wood shoring

under combat vehicles Under special circumstances, height

can reach – 105 inches Practical max width for wheeled

vehicle at floor – 102 inches Practical max width for tracked

vehicle at floor – 100 inches Design guidance published in MIL-

HDBK-1791

105”

Required

JHLA Cargo Bay Design Envelope

The Crosshatched Area Represents The 6-Inch Clearance Required In MIL-HDBK-1791 Between The Payload And Aircraft Structure.

C-17 w/ Similar Cargo Handling C-17 w/ Similar Cargo Handling TechnologyTechnology

Palletized System Retracted

Mission ComparisonMission Comparison

Mission Fuel(#) Rng(NM) Wto(#)

1) VTOL(design mission) -w/cargo drop 22,661 600 132,766

2) VTOL -no cargo drop 22,946 600 133,050

3) Ferry(CTOL) -no cargo,w/ fans 22,661 1,050 95,103

4) Ferry(CTOL) -w/cargo,w/fans 22,661 610 132,766

5) Ferry(CTOL) -fuel vice fans 62,161 2124 132,766

6) Ferry(CTOL) -fuel vice cargo 60,161 2,815 132,766

Fan Fan Design Design

Lift Fan PropulsionLift Fan Propulsion Fixed Parameters

– Air, Standard Sea Level, Standard Hot Day• Fixes , Cp, R, Tt1, and pt1

– Inlet, Fan, Nozzle Efficiencies, d, ef, n Variables

– Hub to tip Ratio, r– Diameter of Intake, D (Inlet Area, fan size)– Through flow Mach number, MA1

– Fan Pressure Ratio, f

Results– Thrust, Power, Mass Flow Rate– Exit: Mach Number, Velocity, Area

Lift Fan Calculation Results for JHL Lift Fan Calculation Results for JHL 60,000 lbs Thrust60,000 lbs Thrust

Lift Fan Design AnalysisLift Fan Design Analysis

Euler Turbine Theory Select

– Fan Tip Speed– Mass Flow– Hub/Tip Ratio– Solidity– Blade Aspect Ratio– Diffusion Factor– Relative Inflow Angle

Accounts for Losses– Boundary Layer

Blockage– Inlet and Nozzle Losses– Shock Losses

Results– Diameter– Blade Geometry

• #Blades • Blade Chord• Blade Spacing

– Thrust– Power Required– Pressure Ratio– Temperature Ratio– Flow Properties Along Blades

• Flow Angles• Diffusion Factors• Pressure and Temperature

Ratios• Shocks

Lift Fan DesignLift Fan Design

Diameter 11.92 ft

Mass Flow 3250 lbm/s

Utip 1000 ft/s

Hub/Tip Ratio 0.3

1m 54.9o

MA1 0.423

Pressure Ratio 1.2449

Temperature Ratio 1.0699

Thrust 59,529 lbf

Power 39,667 hp

Lift Fan GeometryLift Fan Geometry

Blade Geometry

R/RbarChord/ Spacing

Setting Angle

Diffusion Factor

Rotor

Aspect Ratio: 6

Solidity: 1.25

# Blades: 44

0.4615

1

1.5385

3.83”/3.06”

8.30”/6.64”

12.77”/10.22”

-4.6o

44.6o

62.4o

0.3894

0.4636

0.2523

Stator

Aspect Ratio: 8

Solidity: 1.25

# Blades: 58

0.4615

1

1.5385

2.91”/2.33”

6.30”/5.04”

9.69”/7.75”

28.7o

17.9o

12.5o

0.7966

0.4218

0.2635

Lift Fan SizeLift Fan Size

1. OD ~12ft2. Inlet/Diffuser

(unknown)3. Inlet Guide Vanes

(8”)4. Fan Blades (6”)5. Stator Vanes (10”)6. Nozzle (unknown)7. Weight ~ 2500 lbs

The Fan NozzleThe Fan Nozzle

Controllability– Must be able to control

the flow to provide fore/aft thrust control.

– Necessary for transition for takeoff and landing.

Shroud– Wing Space is insufficient.

Louvered Nozzle– Practical, but effectively

reduces nozzle area as the louvers pivot fore and aft.

“Structural Nozzle”– Can provide structural

strength for wing.

– Will allow nozzle contraction to take place over a small distance.

– Allows louvers to direct flow without reducing nozzle area.

Adjustable Nozzle– Increase nozzle area as

louver pivot fore or aft to compensate for effective area reduction.

Lift Fan ControlLift Fan Control

Variable Geometry Inlet Guide Vanes– Provides rapid thrust changes without changing fan

RPM.

Variable Fan RPM– Performance will vary with RPM as engine changes

operating RPM.

Final Engine Final Engine Design Design

Engine Design ProblemEngine Design Problem Engine must be designed to meet shaft power

requirements.

LP Turbine is unmatched with the LP compressor.– Able to deliver shaft power for lift fan– LP spool Over-speeds during cruise operations

unless controlled.– HP spool forced to operate at lower RPM during

cruise

Alternately, designing for cruise leaves HP Spool incapable of producing sufficient flow to produce shaft work necessary for lift fans.

Mismatched Engine Mismatched Engine SolutionsSolutions

Variable Stator in LP spool turbines– Adjust turbine power

output to meet shaft work requirement without over-speeding turbine in cruise.

– Would allow the HP spool to operate at higher RPM, and efficiency, in cruise producing lower TSFC.

– Currently lack the design tools to be able to predict performance, especially off-design.

Secondary Nozzle– Limit LP spool RPM to 102%

– Contract the nozzle to adjust to lower mass flow.

– Bleed fan air into secondary nozzle (eliminates choking in mixer) to improve performance without losing thrust

– Variable bypass engine could achieve similar results, limited design tools make designing with this method simpler.

Mismatched Engine Mismatched Engine SolutionsSolutions

Hover Settings– 60/40 Split of Power

from LP Turbine• 60% to Lift Fan,

Accessories and Losses

• 40% to LP Compressor

– Nozzle Full Open

– No Bypass Air Bleed

Cruise Settings– 5/95 Split of Power

from LP Turbine• Main Gear Box and

Accessory Loads

– Reduce Nozzle Area 40%

– Bleed 60% of Bypass Air to Secondary Nozzle

The EnginesThe Engines Size

– Outside Diameter ~ 6.5’– Length ~ 14’– Nozzle Diameter ~ 4’– Weight ~ 8,500-9,500lbs

Specifications at Design Point– ByPass Ratio ~ 0.3– Fan Pressure Ratio ~ 1.6– Overall Pressure Ratio ~ 41.6

(3.5 LP, 12 HP)– Max Burner Temp ~ 3200oR– LP Spool RPM ~ 10,000– HP Spool RPM ~ 40,000

LP Spool Mechanical Efficiency Modeled at 0.4 to develop required power for lift fans

Design Point– High, Hot Hover

• 4000’ PA

• 95oF

Design Requirements– 15,000 lbf Thrust

– 50,000 shp for Lift Fan Performance at Design Point

– 15,317 lbf Thrust

– 49,840 shp for Lift Fan

– TSFC 1.492 for engine thrust, overall TSFC 0.304 for hover

– Mass flow ~ 387 lbm/s (465 lbm/s corrected, Inlet)

– Core Mass Flow ~ 298 lbm/s (128 lbm/s corrected, HPC)

Engine Off-Design PerformanceEngine Off-Design Performance

Description HHH Hover SSL Hover Cruise Ingress Max SSL Hover Max Cruise Max IngressAltitude ft 4000 0 25000 5000 0 25000 5000

Equivalent Airspeed knots 0 0 284 328 0 284 328Mach Number 0 0 0.7 0.54 0 0.7 0.54

Net Thrust lb 15321 15039 3124 2961 19093 6932 9403Auxillary Nozzle Thrust lb 0 0 2932 4490 0 2339 5321Total Engine Thrust lb 15321 15039 6055 7452 19093 9271 14724Sp. Fuel Consumption lb/(lb*h) 1.49 1.36 1.75 2.58 1.48 1.24 1.44

TSFC with Aux nozzle lb/(lb*h) 1.49 1.36 0.90 1.02 1.48 0.93 0.92Bypass Ratio 0.30 0.36 0.82 1.06 0.28 0.45 0.66

Overall Pressure Ratio P3/P2 41.6 36.3 25.4 18.3 44.0 36.4 28.7Nozzle Throat Mach Number 0.745 0.686 1.000 0.808 0.772 1.000 1.000

Nozzle Pressure Ratio 1.43 1.36 2.07 1.53 1.47 2.70 1.99Total Mass Flow W2 lb/s 387.0 438.0 239.2 384.2 469.4 255.6 449.8

Total Inlet C Flow W2Rstd lb/s 465.0 442.4 447.6 386.7 474.1 478.2 452.7HPT Power hp 99939 93752 27881 39081 122653 43266 67789LPT Power hp 83090 75848 17367 22851 103195 28244 42856

Shaft Power hp 49854 43233 868 1143 61917 1412 2143HP Spool Speed [RPM] 40003 36485 29653 29440 40133 32116 32441

Rel. Corr. HP Spool Speed 1.000 0.946 0.779 0.761 1.018 0.797 0.789LP Spool Speed [RPM] 10001 9180 9216 8651 10200 10200 10200

Rel. Corr. LP Spool Speed 1.000 0.943 0.993 0.879 1.048 1.099 1.037

DriveshaDriveshaft Design ft Design

Drive Shaft RequirementsDrive Shaft Requirements

Transfer 50,000 shp to the each Lift Fan

Operate at 10,000 rpm Be constructed for a

high survivability rate Maintain the operating

speed clear of critical speeds

Photo courtesy of the Goodrich Corporation.

Supercritical AnalysisSupercritical Analysis Treat each shaft section as a Clamped-Clamped system. Design around the requirements (ω = 10,000 rpm and shp =

50,000). Used an iterative process to obtain optimal critical speed speeds,

while maintaining allowable shear stress values for various materials (under Fsy, the Yield Stress in Shear).

Long Shafts Short Shafts

Length (in) 156 91

Number of 6 2

Total Volume (in̂ 3) 651 187

ngular velocity (rpm) 10000 10000

Material ω1 ω2 ω3

Torque (lb in) 315125 315125 7964 22336 43803

Power (shp) 50000 50000

Outer radius co (in) 4.500 2.250

Inner radius ci (in) 4.350 2.100

thickness (in) 0.150 0.150 ω1 ω2 ω3

Max. Shear Stress (ksi) 17.4 73 5535 15524 30444

Approx. Mat'l Yield Shear Stress (ksi) 87 87

Long Shafts

Clamped-Clamped beam

Titanium Alloy (Ti-6A1-4V)

Clamped-Clamped beam

Natural Bending Vibrations Ti-6A1-4V

Short Shafts

JHL Driveshaft JHL Driveshaft SpecificationsSpecifications

GearboxesGearboxes

Main GearboxProvides no reduction due to the power requirement to the

Fans. 1:1 Reduction RatioIndependent 90 degree gear meshing with the shorter Lift

Fan shafts.Longer shafts from the 119 Engine enter at zero degrees

pitch.

Auxiliary Gearboxes6:1 Ratio90 degree turn upward toward the Lift Fans

Required TechnologyRequired Technology

Materials Propulsion System Lifting Fans Driveshaft Clutch Assembly

Critical Design PointsCritical Design Points

Main Engines• Shaft Horsepower and Thrust Requirements

Lifting Fans• Size / Disk Loading / Fitting into wing

Aerodynamic Properties• Need for prepared landing zone / Fan-Wing incorporation

Stability• Fan louvers / Engine Ducts

Gearboxes/Clutch• Main Transmission / Fan gearboxes / Clutch assembly

Questions ?Questions ?