Presenters:
Stephen Haskins
Adam Edmonds
Philip Halsmer
Kwan Chan
Tyler Hall
Sirisha Bandla
Chris Mueller
Jeff Intagliata
Shaun Hunt
1
Outline
 Mission Statement and Design Mission
 Best Aircraft Selection
 Aircraft Sizing, Carpet Plots, and Performance
 Aerodynamic Design Details
2
Mission Statement
 Bring aircraft developments into the modern age of
environmental awareness by means of innovative
design and incorporating the next generation of
technologies and configurations to meet NASA’s ERA
N+2 guidelines.
 Reduce operating cost in face of rising fuel prices and
consumer pressures to reduce fares.
3
Compliance Matrix
*Boeing 777200LR
NASA
Goals
Compliance
Target
Threshold
Take-off (Nox
(g/kg_fuel)/engine)
44.44
-75%
11.11
-50%
Climb-out (Nox
(g/kg_fuel)/engine)
33.85
-75%
8.4
-50%
Approach (Nox
(g/kg_fuel)/engine)
15.78
-75%
3.9
-50%
5.11
-75%
1.2
-50%
-60%
282.10
-42
241.
-20
Decreased
45.2***
Fuel Performance
(lb_pay.nm/lb_fuel)
2300.
Increase
50%
2500.
Increase
30%
2900.
Take-Off length (ft)
11600.
-50%
5800
<7800
<7800
Goals
New Era
**Emissions Indices (GE90-110B1)
Idle (Nox (g/kg_fuel)/engine)
-60%
-60%
-60%
Noise (Overhead + Sideline +
Approach)
Overhead (dB)
87.50
Sideline (dB)
96.70
Approach (dB)
97.9
***Total (dB)
*Project specific reference aircraft.
**Relative to CAEP 6
***Relative to Stage 4
4
Requirement Benchmarking Matrix
Mission Specific
Parameters
Boeing
Boeing
Boeing
737-9001 757-2001 777-200LR1
MD-831
A3212002
A330Threshold
3002
Cruise Mach
0.785
0.8
0.85
0.76
0.78
0.82
>0.7
Maximum Passenger
Capacity
215
234
440
172
220
335
>200
MTOGW w/ 200
passengers (lb)
174200
255000
766000
160000
200000
460765
-
Max Range at MTOGW
w/ 200 pax (nm)
*n/a
3600
9200
*n/a
2500
5800
>3500
Take-Off Length at Sea
Level at MTOGW (ft)
*n/a
9500
14200
*n/a
7500
6800
<7000
*cannot exceed 200 passengers w/o exceeding MTOGW
1 Courtesy
2 Courtesy
of Boeing online documentation
of Airbus online documentation
Design Mission Concept1
Cruise > 0.7 M
Direct
Climb
Descent
Loiter
Design Range ≈ 3300 nmi
<7000 ft
Taxi and Take Off
(0) -> (4) : ‘Basic Mission’
1Extrapolated
≈ 200 nmi
Land and Taxi
Missed Approach
Land and Taxi
(5) -> (9) : ‘Reserve Segments’
from Raymer, Daniel Aircraft Design: A Conceptual Approach Fig. 3.2
Market Opportunity
 Market niche
 Creating an aircraft that can replace large portions of major airlines’ aging
fleets such as MD-80, Boeing 757, 767 due to evolving market and
economic needs
 Potential customers include airlines such as Delta, American, and
Continental
7
Target Markets
 North America
 Europe
 Predicted second most in demand
 Predicted third most in demand of
of new aircraft between 2010-2029
*(7200 new a/c)
 78% of single aisle purchases are for
airline fleet replacement
 Single aisle a/c market is predicted
to grow from 56% to 71% in next 20
years
new aircraft between 2010-2029
*(7190 new a/c)
 Single aisle a/c are forecasted to
make up 75% of new purchases in
next 20 years
 According to Boeing market
forecast, only 4% of current a/c in
current use will still be flying in
2029
 The European domestic air routes
are all short enough that our a/c can
cover them
* Airlines in both the North American
and European markets are looking
for more fuel efficient and less
pollutant a/c.
*References: Boeing future market forecast, Airbus future market forecast
8
Walk around
Advanced Features
9
Final Concept
 Trade Studies on Final Design
 Eliminated Twin Fuselage – Too Heavy – Extra Parasite
Drag
 HBB - During the trade study of sizing the body,
justification of the faired wing-fuselage intersection was
lacking. (In the process of deciding how big the fairings
should be, we discovered errors in our prior reasoning.
We could not fully justify having such large fairings.)
10
Technologies
 Majority Composite
Construction
 Engine Selection
 Geared Turbofan
 Aerodynamics
 Passive Laminar Flow
Control
 Boundary layer control
 Noise Reductions
 Engine-Air Brake / Quiet
Drag Applications
 Pratt & Whitney PurePower
11
Cabin Dimensions and Layout
Dimensions
Total Length: 150 ft
20 First Class Passengers
Total Width: 10.4 ft
Cabin Length: 118 ft
Cabin Width: 11.1 ft
180 Economy Class Passengers
4 in
67 in
78 in
47 in
Reference: www.seatguru.com
125 in
18
19
Sizing Approach
 Based on Raymer’s sizing approach
 Empty Weight Buildups
 Mission Segment Fuel Weight Buildups
 Drag breakdown

C DO + C DI approach
 Curve fits for engine data
 Carpet plots to optimize W/S and T/W
20
Engine Modeling

Partial Power Model is Semi-Empirical

Verify Model with NASA EngineSim 1.7a



Use General Electric CF6 as baseline engine
Partial Power Model with new Coefficients fitted
Apply New Technology to Partial Power Model
Daniel Raymer Aircraft Design: A Conceptual Approach. p378.
Courtesy NASA.
21
Cruise Performance
0.7
GE CF6 CurveFit Model @ 35k M0.8
GE CF6 EngineSim Model @ 35k M0.8
Raymer PartPower Method @ M0.8
Cruise Power Setting
0.65
0.6
SFC [1/hr]
0.55
0.5
0.45
0.4
0.35
2000
4000
6000
8000
Thrust [lbf ]
10000
12000
14000
Tail sizing strategy
 Using B757 as a reference
 Calculate Tail volume coefficient
 Compare to Raymer
Tail sizing strategy
 One engine out and crosswind:
 Vertical tail large enough to provide side force with
rudder deflection less than 20 deg
 Consider crosswind about 20% Vto




Rotation authority:
Calculate moment of horizontal tail when take off
Compare with moment of c.g.
Main landing gear is the moment reference point
Tail sizing strategy
 Tail volume coefficients: Cht = 1.02 Cvt = 0.11
 Moment arm about 50% of fuselage length
Area (ft^2)
Vertical Tail
Horizontal Tail
348
414
Effect of tail configuration
 T-tail, V-tail and cruciform tail (mid-tail) were considered.
 Avoid engine exhaust
 Cruciform tail:
 Reduce weight penalty to the vertical tail
 Reduce chance of flutter
 Heavier than V-tail
 Will not provide a tail-area reduction due to endplate effect
as will a T-tail
BFL Constraint Crossplots
d_to Crossplot, T/W = .3
10000
d_TO [ft]
The W/S that that violates the
constraint is recorded and plot
on the final sizing plot.
9000
dTO <= 7800
[ft]
8000
7000
T/W = .3
6000
100
120
140
W/S [lb/ft^2]
d_to Crossplot, T/W = .32
d_to Crossplot, T/W = .34
10000
9000
T/W = .32
8000
7000
6000
100
120
140
W/S [lb/ft^2]
dTO <= 7800
[ft]
d_TO [ft]
d_TO [ft]
10000
9000
T/W= .34
8000
7000
dTO <= 7800
[ft]
6000
100
120
140
W/S [lb/ft^2]
27
Sizing Plot
238
W/S vs TOGW with Performance Constraints
236
TOGW [1000 lbs]
234
232
T/W = 0.3
230
T/W = .32
228
226
T/W= .34
224
d_TO <= 7800[ft]
222
Gamma >= .024
220
218
100
110
120
130
140
150
W/S [lb/ft^2]
Minimum TOGW occurs at W/S = 128 lb/ft^2, T/W = .31, TOGW = 224,000 lbs
28
Sizing Plot Constraints
 Balanced field length for takeoff
 7800 ft
 Second segment climb
 Gamma > .024
 Landing Ground Roll
 dLand < 5800 ft
 Not a function of T/W
 Found the max W/S to be 129 lb/ft^2
29
Current Weight Conclusions
 SFC – i
16%
 CD0 – i 10%
 Laminar Control
Bench
mark
New Era
Savings
OEW
131,200
123,000
6%
Wfuel
79,300
51,000
36%
GTOW
260,300
224,000
14%
 Composites
 Higher AR
 Reductions in various
component weights
30
VN Diagram
Never Exceed
Speed
 Used to show the
limitations with regard
to speeds/acceleration
 Shows the amount of
positive or negative lift
that can be generated n
while showing
maximum G the
aircraft can sustain.
Structural
Damage
Acceleration
Stall
C
A
U
T
I
O
N
Normal Operating
Range
 N+ = 2.5
 N- = -1
Structural
Damage
 VS – 130 kts
 VA – 166 kts
 VNO – 469 kts
 VNE – 522 kts
Indicated Airspeed
VS
Stall Speed
VA
Maneuver Speed
VNO
Max Structural
Cruise Speed
VNE
Max Speed
32
Drag Prediction
 Describe Approach
 Component Build-up Method (CDo)



Sum of the subsonic parasite drag from each component
Skin Friction, Form Factor, Interference Scaling Factor, and Wetted
Area
CDmisc added: upsweep, landing gear, leaks/protuberances
 CLalpha estimation (K*CL^2)

Based on Aspect Ratio, Sweep, Mach Number, Airfoil Efficiency,
and Fuselage Lift Factor
 Transonic Wave Drag (CDwave)


Divergence Mach Number, Crest Critical Mach Number, Critical
Pressure Coefficient, Sweep Angle
Mostly Empirical Data
Airfoil Selection
 Wing - DBLA 238
 Checked Empirical
Data based on t/c
ratio, Mach design
range, max thickness
location, and
Supercritical effects
 Tail – NACA 64-012
 Checked Empirical
Data based on Stall
angle and Zero-Lift
angle
High-Lift Devices
 Slotted Leading Edge Flap (Slat)
 Double Slotted Flaps
 CLmax
 Cruise: .95
 Takeoff: 2.3
 Landing: 3.1
Drag Polars
Drag Polars for Different Mission Segments
0.14
 Estimated by changing Mach,
0.12
0.1
D
0.08
C
Angle of Attack, and Effective
Wetted Area for each different
segment
 CD values were then found as a
function of a range of CL values
Landing
Takeoff
Cruise
0.06
0.04
0.02
0
-1.5
Drag Polar for Takeoff Conditions
-1
Drag Polar for Landing Conditions
0.14
Total CD
CDwave
CDo
CDi
Total CD
CDwave
CDo
CDi
0.12
0.08
C
C
C
D
0.08
D
0.08
D
0.1
0.06
0.06
0.06
0.04
0.04
0.04
0.02
0.02
0.02
-0.5
0
CL
0.5
1
1.5
1
Total CD
CDwave
CDo
CDi
0.12
0.1
-1
0.5
0.14
0.1
0
-1.5
0
CL
Drag Polar for Cruise Conditions
0.14
0.12
-0.5
0
-1.5
-1
-0.5
0
CL
0.5
1
1.5
0
-1.5
-1
-0.5
0
CL
0.5
1
1.5
1.5
37
Propulsion Overview
 Geared Turbofan
 Technology Readiness
Requires
 Producibility
 Stabilized Performance
 Supportability
 P&W PurePower Specs
 Reduced SFC by 16%
 High BPR of 12:1
 NOx emissions 55%
below CAEP/6
 Reduced Carbon
Emissions
 PureSolution MRO
services
MRO - (Maintenance, Repair, and Overhaul)
John W. Lincoln – Technology Transition to New Aircraft. 1987
Courtesy: Pratt & Whitney
Installed Performance Assumptions
 Future Technology
 32% percent SFC reduction
 50% reduction in NOx
 Neglect Subsonic Inlet and Nozzle Pressure Losses
 Inlet Drag Estimation* (per engine)
 Bleed Power Loss Estimation* (per engine)
 Assume Bleed Mass Flow 3% of engine mass flow
*Daniel Raymer Aircraft Design: A Conceptual Approach. p374 &
p377.
Engine Size
 -Turbofan empirical
data
 -Engine weight,
length, diameter and
fan diameter versus
dry thrust.
 -Curve fit function
Data from http://www.jet-engine.net/civtfspec.html
40
Engine Dimension
Data from http://www.jet-engine.net/civtfspec.html
Dry Thrust
40k
GE CF6-6
Estimation
Weight (lb)
7350
7090
Length (in)
173
143
Diameter (in)
87
78
Fan Diameter
(in)
92
80
41
Engine Emissions
Dp/Foo vs Over all pressure ratio
NOx
130
120
110
CAEP/2
100
CAEP/4
CAEP/6
90
60% Below CAEP/6
Dp/Foo (g/KN)
80
70% Below CAEP/2
50% Below CAEP/2
70
75% Below CAEP/6
60
50
40
GE-90-110 B1
(B-777-200LR)
30
CF6-80C2B8F
20
Our Engine
10
0
15
20
25
30
35
40
45
50
55
60
OPR
42
Important Load Paths
Lift
Drag
Thrust
Weight
Items considered when designing
the structure:
•Bending and Torsion Loads
•Pressure Loads
•Buckling of the wing
Internal Structure
Windows/Doors:
Windshield, doors and
windows will have a frame
around them to increase the
strength in that particular
area.
Engine Pylons:
-Bulk head will reinforce
engine mounts in the wing.
-Rib and spar design will be
implemented in the pylons,
constructed of higher strength
material.
Fuselage:
-Semi-Monocoque
construction consisting of
stressed skin with stringers
and longerons attached to
hoop-shaped frames
Wing:
-Ribs will maintain shape of the wing.
-Ribs will be supported by spars.
-Skin of the wing will carry the pressure
loads.
-Torsion box structure (not pictured) will be
incorporated into wing design
Special Considerations
Flat disk Pressure
bulkheads will close
the cabin on both ends
and carry the loads
induced by
pressurization
Wing box has a carry
through section in the
lower part of the
fuselage
Landing gear to
fuselage intersection
will be reinforced with
a stiffener made with
higher strength
material
Material Selection
Composites 50%
•Light weight
•Strong
•Higher resistance to corrosion
•Costly
•Increased options during the lay-up process
Advanced Aluminum Alloys 25%
•CentrAl - Fiber metal laminate reinforced by high-quality aluminum
•Alleviate fatigue issues
•Reduce maintenance costs
•Less sensitive to damage caused by
Titanium 10%
Steel 10%
Other 5%
Composites
Steel
Advanced Aluminum
Alloys
Titanium
Other
48
Empty Weight Components
Component
 Component build up
method (Raymer)
 Wing, Horizontal Tail
and Vertical tail are
dynamic
 Composite structure
was taken into
account with a ‘fudge’
factor (Raymer)
 0.9 for wing
 0.88 for tails
 0.95 for fuselage
Wing
Horizontal Tail
Weight (lbs)
28063
1100
Vertical Tail
1948
Fuselage
22572
Nacelles
5073
Landing Gear
1272
Landing Gear
7955
Engine
Engine Controls
Starter
23746
51.36
312
Fuel System
1714
Flight Controls
2133
Aux Power Unit
1521
Instruments
360
Hydraulics
262
Electrical
2860
Avionics
1962
Furnishings
16725
Air Conditioning
Anti-Ice
Handling Gear
Total Weight
3300
560
84
123573.36
Location of center of gravity
 Weight of parts from empty weight function
 Location of all the parts
Location of center of gravity
 Four fuel tanks
 C.G. shift during flight
 Depends on fuel tanks position.
Location of C.G.
Most forward
Most aft
64.6ft
63.7ft
65.5ft
* From nose
Longitudinal stability
 Neutral point and static margin
 Static margin about 15% of the mean aerodynamic
chord
Neutral point
Static margin
67.3ft
15%
Control surface size
 Elevator:
 Begin from the side of the Vertical tail extend to 90%
of the horizontal tail span.
 40% of the tail chord





Aileron:
Outboard – low speed * Avoid aileron reversal
Inboard – high speed
From 50% to 90% of wing span
20% of the wing chord
Control surface size
 Rudder:
 One engine out and cross wind
 Calculate rudder size based on yawing moment from
one engine at full thrust and crosswind of 20% Vto.
 Begin from fuselage 50% of vertical tail span
 40% of tail chord
55
Means of Aircraft Noise
Reduction
 Pratt & Whitney PurePower1 Geared Turbofan Engine
 Engine Air Brake2
 Engine Placement
(Due to the Noise Shielding form the Body Itself)
56
Engine Air Brake
Integrate swirl vanes into
the mixing duct
• Swirling exhaust flows can generate drag quietly – demonstrated
drag coefficient near one at ~44 dBA full-scale
• Engine air-brake application for quiet, slow / steep approach
profiles
(estimate up to 6 dB for 3 degree change in glideslope)
57
Source: http://ns1.nianet.org/workshops/docs/QA/presentations/FSIS/Spakovsky.pdf
Method of Calculation
 Pratt & Whitney PurePower1 Geared Turbofan is
projected at 20 dB below the Stage 4 noise limit
 The Engine Air Brake2 is proposed to reduce approach
noise by 6 dB
 Corrections for sound propagation, engine effect, and
airframe effect using an estimation method proposed
by Stanford professor Ilan Kroo
 The sound propagation is attributed to the altitude at
flyover and the distance from the sideline
58
Noise Levels
NASA N+2 : 241 dB
Current Design: 237.8 dB
Takeoff [dB]
Sideline [dB]
Approach [dB]
Total [dB]
Stage 4
90
95
98
283
Current Design
77.4
79.9
86.5
243.8
Current Design
(with Engine Air
Brake)
77.4
79.9
80.5
237.8
59
60
Cost
 Methods Used to Estimate Cost
 Number of Aircraft in Production Run
 Estimated Cost of Development, Manufacturing, and
Purchase
 Estimated Operating Cost
Cost Estimation Method
 RAND DAPCA IV Model used from Raymer’s text.
 Estimates Development and Procurement costs.
 Includes hours required and wrap rates for labor costs.
 Technology Factoring.
 Accounts for increases in Development and
Manufacturing costs for new technologies.
 Also includes reductions for Operating Costs.
 Empty Weight, Quantity in Production Run, and
Velocity were major contributors.
Cost Assumptions
 From market analysis, 2000 a/c are expected to be
produced to supply the Asia Pacific and American
markets.
 200 a/c for first 5 years production is needed for the DAPCA IV Model.
 5 test aircraft to be produced.
 Aircraft assumed to fly 3500 block hours.
 2 pilot crew and 4 flight attendants.
 Cost of Jet-A fuel estimated at .76¢/lb.
 From IATA estimations on weekly price average.
 Insurance rate: 1.5%
Development Cost Analysis
Development Cost Breakdown
2011 Dollars
Development Support Cost
354,000,000
Flight Test Cost
112,000,000
Manufacturing Materials Cost
3,215,000,000
Engine Production Cost
6,630,000
Avionics
700,000,000
Interior Furnishings
500,000
Interior costs estimated at $2500 per passenger from Raymer
Hourly Rates
1999 $
2011 $
Engineering
86
115
Tooling
88
118
Quality
81
109
Manufacturing
73
98
*Wrap rates from Raymer 18: Increased 34% for inflation from United States Department of
Labor.
RDT&E and A/C Cost
 The total cost of the RDT&E + Flyaway cost is:
RDT&E + Flyaway Cost
$19.7 Billion
 The cost per aircraft comes to:
Cost of A/C
$131 million
 This is with the inclusion of inflation rates from 1999 to 2011 and an
investment rate of 10%.
Depreciation/year
$8.9 million
Insurance/year
$1.8 million
 For our project to reach the breakeven point,
150 a/c will need to be sold.
Operating Cost Estimates
Operating Cost Breakdown
Value ($)
Total Direct Operating Cost
Variable Cost
8350/BH
6000/BH
Fuel Consumption
4600/BH
Tax
200/BH
Landing Fee
1200/BH (avg)
*based on MTOW
Fixed Cost
2350/BH
Crew and Attendants
717/BH
Maintenance
1600/BH
Hangar/Training Fees
35/BH
*All calculations done for design mission (3000 nm.)
Conclusion
 Thank you Professor Crossley and Stephan Lehner
 Thank you Boeing for your feedback and time
 Next, NASA’s Environmentally Responsible Aviation
Challenge
 Gained valuable experience and knowledge
 Questions?
67
68