RD II
Rotorcraft Design II:
Preliminary Design
Dr. Daniel P. Schrage
Professor and Director, CERT & CASA
School of Aerospace Engineering
Georgia Tech, Atlanta, GA
Daniel P. Schrage
Georgia Tech
RD II
Course Outline
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Review of Conceptual Design Solutions
Conceptual Design Issues for Resolution
Structural Design
Dynamics
Stability and Control
Drive System Design
Life Cycle Cost
Power Plant Selection and Installation
Secondary Power Systems
Weight and Balance
Maintainability
Reliability and Availability
Configuration and Arrangement
Daniel P. Schrage
Georgia Tech
RD II
Georgia Tech Evolving Rotorcraft Preliminary
Design Methodology
PRODUCT DEVELOPMENT
Requirements
Analysis
(RFP)
Baseline Vehicle
Model Selection
(GT-IPPD)
New Design
Vehicle Engineering
Analysis
(CATIA)
PROCESS DEVELOPMENT
Baseline Upgrade
Targets
Upgraded/Derivative. Design
Vehicle Sizing &
Performance
(RF Method)
(GTPDP)
Linear Static
Structural Analysis
(CATIA-ELFINI)
Virtual Product Data
Management
(ENOVIA)
Preliminary Vehicle
Configuration Geometry
(CATIA)
Aerodynamic
Performance
Analysis (BEMT)
Manufacturing
Processes
(DELMIA)
Vehicle Assembly
Processes
(DELMIA)
Support Processes
(DELMIA)
Propulsion
Performance
Analysis
Vehicle Operation
Safety Processes
(DELMIA)
Noise/Vibration
Characteristics
Analysis (LMS)
FAA Certification
Multi-Body, Non-Linear
Dynamic Analysis
(DYMORE)
Linear & Non-Linear
Structural Analysis
(NASTRAN/ABAQUS)
Stability and Control
Analysis
(MATLAB/LMS/CATIA)
Daniel P. Schrage
Georgia Tech
Reliability Modeling
(PRISM)
Revised Preliminary
Conceptual Design
(CATIA)
Light HelicopterGTX
Final Proposal
Cost Analysis
(PC Based Cost
Model)
Overall Evaluation
Criterion Function
Present Conceptual and
Preliminary Design Approach
Product Development
Requirements Analysis
(RFP)
Baseline Model Selection
(IPPD)
Dynamic Analysis
(DYMORE)
Baseline PDS
Targets
Vehicle Sizing &
Performance
(RF Method)
(GTPDP)
Operations & Support
Processes
Safety Processes
Reliability Modeling
(PRISM, etc.)
Preliminary
Design
ITU LCH
Final Design
Daniel P. Schrage
Georgia Tech
Manufacturing
Processes
Engine Model
Structural Analysis
(NASTRAN)
Stability and Control
Analysis (MATLAB)
Process Development
FAA Certification/
Mil Qualification
CBEM
Geometry/Static Analysis
(CATIA)
RD II
Cost Analysis
(PC Based Cost Model)
Overall Evaluation
Criterion Function
RD II
2003 AHS Student Design Competition: VTOL
Urban Disaster Response Vehicle (VUDRV)
(Sponsored by Sikorsky Aircraft and NASA)
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Critical Milestones
Response Requirements
Competition Judging Criteria
Conceptual Exploration Status
Conceptual Design Issues for Resolutions
Recommended Conceptual and
Preliminary Design Approach
Daniel P. Schrage
Georgia Tech
RD II
VUDRV Critical Milestones
• Release of RFP:
October 21, 2002
• Notice of intent to Compete: October 28, 2002
• Teleconference w/Sikorsky: Oct 30,2002
on Problem Statement
• Additional teleconferences: As Required
• 2 page emerg results sumry: Feb. 15, 2003
• Final report due:
June 15, 2003
• Winners announced:
August 1, 2003
Daniel P. Schrage
Georgia Tech
RD II
VUDRV Response Requirements
• A written report limited to100 pages shall provide the
following:
– Executive Summary (5 page summary of entire report & key findings)
– Description of operational environment and mission requirements (add
critical requirements identified during concept exploration)
• Detailed mission profiles shall be recommended for the following
missions:
–
–
–
–
–
–
Daniel P. Schrage
Georgia Tech
High rise Firefighter deployment
Roof Occupant extraction
Building face penetration and occupant recovery
Ground pump water cannon fire fighting
Self contained tank water cannon fire fighting
Disaster command and control
RD II
VUDRV Response Requirements
• A written report limited to100 pages shall provide the
following (continued):
– Concept evaluation and down-selection process and rationale
– Selected Concept Preliminary Design
• Overview including concepts sketches in each mission role
• Day in the life of the system description
– Timeline from 911 call to end of day
• Vehicle Subsystem descriptions
– (airframe, rotors, drive, controls, avionics, landing gear…)
– Include rationale for recommended subsystem technical
approach
• Avionics system description including proposed operator interface
• Mission kit descriptions as required for each mission
• Weight empty derivations for primary vehicles
• Mission gross weight derivations for each mission
• Performance estimates and plots for each mission
– Such as time on station vs number of occupants recovered for
building face extraction
Daniel P. Schrage
Georgia Tech
RD II
VUDRV Response Requirements
• A written report limited to100 pages shall provide the
following (continued):
– Compliance matrix showing compliance with all
technical/mission requirements
– Non-recurring and recurring unit cost estimates
– Development schedule
– Risk identification and Risk Reduction plan
– Recommendation of how many systems would be required per
100,000 person city population
– Concept sketch of future urban fire station with mix of ground
vehicles and proposed system(s)
Daniel P. Schrage
Georgia Tech
RD II
VUDRV Competition Judging Criteria
• Innovation: 40%
– Study shows ability to depart from conventional thinking and
paradigms to explore potentially high value solutions
• Understanding of the Problem: 10%
– Study clearly demonstrates understanding of the real world
mission problem and the associated technical challenges
• Technical Content: 30%
– Analysis and data is accurate and all methods used are well
understood. Underlying principles are well understood.
• Clarity: 20%
– Report is clear, concise, and develops compelling case for
proposed solution. Emphasis is on clear graphics and diagrams
to illustrate points and concepts
Daniel P. Schrage
Georgia Tech
RD II
Review of VUDRV Conceptual
Exploration Status
• Conceptual Design Selection still incomplete;
however, not a problem based on RFP
Requirements which places more emphasis on
requirements, mission and operational analysis
• Initial Requirements Analysis well done and
resulted in initial functional and resulting
performance requirements
• More detailed mission and operational analysis
required to further verify the performance
requirements for concept selection
Daniel P. Schrage
Georgia Tech
Define the Problem  Requirements Analysis
RD II
VUDRV Modes of Operation
• High-rise Firefighter
Deployment
– 15 Fire Fighters to Rooftop
– 2 minute Cycle
• Rooftop Occupant
Extraction
– 1200 People/Hour
• Building Face Penetration
/ Occupant Recovery
– 800 People/Hour
Daniel P. Schrage
Georgia Tech
• Ground Pump Water
Cannon Fire Fighting
– Lift 5” Diameter Hose 1000
feet
• Onboard Tank Water
Cannon Fire Fighting
– 500 Gallon Tank; Refill in
60 seconds
• Disaster Command and
Control
– Occupant Locator
– Information Gathering /
Transmitting
Define the Problem  Requirements Analysis
VUDRV Operational Scenarios
Daniel P. Schrage
Georgia Tech
RD II
Define the Problem  Requirements Analysis  Operational Scenarios RD II
VUDRV High-rise Firefighter Deployment
Off Load Firemen
REPEAT
System Endurance > 1
Hour
1500
Feet
Radius of Action
20 naut. Mile
Land to Load Firemen
time = 120 sec
REPEAT
Land to Load Firemen
time = 0 sec
Daniel P. Schrage
Georgia Tech
15 Firemen X 300 lbs.
4500 lbs.
Define the Problem  Requirements Analysis  Operational Scenarios RD II
VUDRV Rooftop Occupant Extraction
Extract Occupants
REPEAT
System Endurance > 1
Hour
REPEAT
Unload Occupants
1200 rescues/hour
Rooftop
Unload
Location
Unload Occupants
1200 rescues/hour
Gro
und
1500
Feet
REPEAT
Radius of Action
20 naut. Mile
Daniel P. Schrage
Georgia Tech
Land to Offload
Mission Supplies
time = 0 sec
Define the Problem  Requirements Analysis  Operational Scenarios RD II
VUDRV Building Face Penetration
Occupant Extraction
Extract
Occupants
From Building
Face
System Endurance > 1
Hour
Unload Occupants
800 rescues/hour
Rooftop
REPEAT
Unload
Location
REPEAT
Unload Occupants
800 rescues/hour
Gro
und
1500
Feet
REPEAT
Radius of Action
20 naut. Mile
Daniel P. Schrage
Georgia Tech
Land to Offload
Mission Supplies
time = 0 sec
Define the Problem  Requirements Analysis  Operational Scenarios RD II
VUDRV Water Cannon Fire Fighting
Ground Pump
Radius of Action
Fight Fire Using
Water Cannon
20 naut. Mile
Land to Unload
Mission Supplies
Hook up to Ground
Water Pump Station
Daniel P. Schrage
Georgia Tech
5" Diameter
Water House
1500 gpm
1000 ft.
min
Define the Problem  Requirements Analysis  Operational Scenarios RD II
VUDRV Water Cannon Fire Fighting
Onboard Tank
Refill Tank
60 seconds
Radius of Action
Any
Floor
Fight Fire Using
Water Cannon
20 naut. Mile
500 gallon
On-board Tank
Land to Unload
Mission Supplies
Hook up to Ground
Water Pump Station
Daniel P. Schrage
Georgia Tech
Define the Problem  Requirements Analysis  Operational Scenarios RD II
VUDRV Disaster Command & Control
Develop Horizontal and Vertical
Tactical Displays with Overlay of
Information, Schematics, Maps, Etc.
Communicate Data and
Decisions to Network on
Ground and in Air
System Endurance > 2 hours
1 hour at hover
1 hour at 60 knot cruise
Land to Offload
Mission Supplies
time = 0 sec
Radius of Action
20 naut. Mile
Daniel P. Schrage
Georgia Tech
Multiplexed
Communication
Minimum of 4 personnel to
Operate Command Center
Define the Problem  Requirements Analysis
VUDRV Utilization Environments
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Urban Canyon
Low to Zero Visibility
Turbulent Air
High Temperature Exposure
Extreme Weather Conditions
Road Transport
Daniel P. Schrage
Georgia Tech
RD II
Define the Problem  Requirements Analysis
RD II
VUDRV Functional Requirements
Payload Capacity
300 lb
Person
200 lb
Person
FFD
15
RTOE
Mission
Internal
Module
(assumed)
(assumed)
Persons
Water
External
Total
0
612
1,000
4,500
0
5,500
6,112
0
70
612
1,000
14,000
0
15,000
15,612
BFPOE
2
70
612
1,250
14,600
0
15,850
16,462
DWCFFgp
0
0
612
750
0
8,500
9,250
9,862
DWCFFip
0
0
612
750
0
4,164
4,914
5,526
CAC
0
4
612
2,000
800
0
2,800
3,412
Daniel P. Schrage
Georgia Tech
Define the Problem  Requirements Analysis
RD II
VUDRV Performance Requirements
Useful Load:
16,500 lbs.
Forward Speed: 60+ knots
VROC5500 lbs.:
2500 ft/min
Hover Ceiling:
7,000+ ft ASL
OEIHOVER:
6000 ft ASL / 16,500 lb.
Endurance:
1 hr. hover / 1 hr. cruise
Daniel P. Schrage
Georgia Tech
RD II
VUDRV Conceptual Design Issues
for Resolution
• Is a new or derivative aircraft the preferred
solution? (depends on the time frame when the
system must be operational)
• The system is more than the vehicle; emphasis
is on addressing the ‘system of systems’
• Strong emphasis must be placed on
reconfigurability of the system for the different
missions
• Strong emphasis must be placed on automatic
flight control and sensor sub-systems
Daniel P. Schrage
Georgia Tech
RD II
Recommended Conceptual and
Preliminary Design Approach
• Should spend substantial more effort on
completing the Conceptual Exploration and
Design Effort
• Need to reach a decision on new or derivative
system for the air vehicle (suggest telecon with
Andy Keith, Sikorsky)
• Explore the use of the ASDL Mission and Unified
Tradeoff Environment (UTE) for evaluating
combinations of requirements, concepts and
technologies (See Dr. Dan DeLaurentis, ASDL,
A. Baker Ph.D Thesis)
Daniel P. Schrage
Georgia Tech
RD II
Requirements (Mission) Space
• Concept Space - vehicles attributes used as factors in DoE, built
around baseline vehicle
• Technology Space - technology metric dials used as factors in DoE,
built around baseline vehicle
• Mission Space
• Compatibility with Concept Space and Technology Space
• Mission requirements used as factors in DoE, built around
baseline vehicle
• Based on a Master Mission Structure which captures primary
missions and provides reference point for understanding mission
parameter effects on system sizing.
• Allows capture of multiple missions and provides continuous
mission space
• Secondary missions flown after sizing to determine performance
Daniel P. Schrage
Georgia Tech
RD II
Master Mission Structure
Cruise 3 Combat Radius
Cruise 3 Temperature
Cruise 3 Altitude
Cruise 1 Combat Radius
Cruise 1 Flat Plate Drag Area
Cruise 1
Cruise 2
Cruise 3
Taxi / Warm-up
Hover 1 (OGE)
Hover 1 Time
Vertical ROC
Payload
Mid Hover (OGE)
Drop Payload
Hover 2 (OGE)
Payload Dropped
Hover 2 Time
Common Requirements
Altitude
Temperature
Daniel P. Schrage
Georgia Tech
Fuel Reserve
Velocity Best Endurance
Time
30 min
RD II
Functionally Relating Responses and Inputs
Objective (O) or
System Level
Attribute (SLA)
Top-Level
requirements
related to the
mission
Vehicle Attribute
Variables
Response = fcn (Requirements, Concepts, Technologies)
 Potentially large number of inputs;
 To cope, evaluate response in “snapshots”,
where most inputs are held constant while a
subset of the inputs varies
 Each “snapshot” computes “deltas” in
responses with respect to a baseline
 This approach allows the additive
combination of the effects of concepts,
technologies, and requirements on the
decision-making space
Daniel P. Schrage
Georgia Tech
Technology Dials
(related to product
and/or process)
RD II
Unified Tradeoff Environment
• What is needed is a design environment that allows the designer to
assess the simultaneous impact of changes in mission requirements,
vehicle attributes and technologies while being amenable to
probabilistic techniques.
• Whether constructed as an integrated environment or built from
individual spaces this design environment is called the Unified
Tradeoff Environment (UTE).
• Integrated UTE
• Multi-Space UTE
• Most logical breakdown considers design spaces already created.
• Concerns with multiple spaces.
Daniel P. Schrage
Georgia Tech
Multi-Space Unified Tradeoff
Environment
RD II
 Responses
Baseline +
Technology Space
(Technology Dials)
 Responses
Concept Space
(Vehicle Attributes)
 Responses
 Responses
Mission Space
(Mission Requirements)
Mission Requirements
Vehicle Attributes
Snapshot 1
Fixed Geometry, Technology Set
Daniel P. Schrage
Georgia Tech
Snapshot 2
Fixed Requirements, Technology Set
Technology Dials
Snapshot 3
Fixed Requirements, Geometry
RD II
Concerns with Multi-Space UTE
Rbaseline +
Mission Space
?
Mission Requirements
Ri  bo 

i 1
bi xi 
k

i 1
bii xi2 
k 1
 Responses
 Responses
 Responses
?
k
Technology Space
Concept Space
Vehicle Attributes
Technology Dials
k
  bij xi x j
i 1 j  i 1
Ri  bo 
k
k
i 1
i 1
 bi yi  
bii yi2 
k 1
Ri  bo 
k
  bij yi y j
k
k
i 1
i 1
 bi zi  
bii zi2 
k 1
k
  bij zi z j
i 1 j  i 1
i 1 j  i 1
• Independence - Correlation
Engineering Knowledge/Analysis Codes
• Across-Design-Space Interactions
Modified Screening Test
• Sizing Effects
Sizing Variables
Daniel P. Schrage
Georgia Tech
RD II
ITU LCH Conceptual and Preliminary
Design Effort
• Baseline Istanbul Technical University
(ITU) Light Commercial Helicopter (LCH)
Prototype Requirements
• Status of ITU LCH Conceptual Design
effort
• Proposed approach for conducting the ITU
LCH Preliminary Design effort
Daniel P. Schrage
Georgia Tech
RD II
Baseline ITU Light LCH Prototype
Requirements
• A Challenging set of requirements were provided
to GIT and ITU Student Design Teams
• Results from GIT and ITU individual and team
design efforts appear to substantiate the
feasibility of meeting the requirements
• A baseline ITU LCH Conceptual Design has
been established
• Some refinements to the ITU LCH Conceptual
Design will be made and an ITU LCH Product
Design Specification (PDS) established
Daniel P. Schrage
Georgia Tech
RD II
ITU LCH Specification Summary
Tip Speed
Seating
2 crew, 4 pax (6 high density)
Disk Loading
Anti-torque
NOTAR
Solidity 
Hub
Hanson EA
# Blades
Engine
GAP Turboshaft 500 Hp MCP
Disk Area
Transmission
650 shp COTS
TOP
MR Radius
MR blade chord
Landing Gear
Metal Skid
MR blade twist
Flight Controls
Mech push-pull

SCAS
Electric Yaw SAS
MR blade AR
Airfoil
VR-7
Lock number
Drag polar
Cd = .0081 + .4494* 2
Max Lift curve slope
Blade loading
WG
3950 lb
Blade lift
WE
1660 lb
CF (each blade)
WU
1500 lb
Blade tip weight
WF
790 lb
Rotor Polar Moment
Fuel cap.
116.2 gal
Flare Factor
EW/GW
0.42
flat plate drag area
Height
9 ft
Ixx
Width (max)
6 ft
Iyy
Length
31.25 ft
Izz
Daniel P. Schrage
Georgia Tech
650
5.48
0.07
4
721
15.15
0.83
-12
42.9
18.26
6.45
6.45
78.6
988.36
20486.8
6
604
51.3
10
421.015
1015
853.485
fps
lb/sqft
sqft
ft
ft
deg
per rad
lb/sqft
lb
lb
lb
slug-ft2
sqft
slug-ft2
slug-ft2
slug-ft2
ITU LCH Conceptual Design Summary
RFP
Performance
Gross Weight
OGE Hover Ceiling
Cruise Speed
Range
Actual
< 4500 lbs
3950
10,000 ft ISA +20 deg
No
> 120 kts
123
>350 (w/20 min reserve
381
Stability & Control
Useful Load
Cost
Maintainability
Reliability
Weights
Noise
Avionics
English/Metric
Daniel P. Schrage
Georgia Tech
Cooper/Harper Rating
Training Time
Very Safe
Cockpit seating
Cabin seating
Acquisition (2002 $)
DOC
Airframe
Maint. Man hr/flt hr
Total System MTBF
EW/GW fraction
External:
MR Tip Speed
TR Tip Speed
Internal
Utility Version
Exec. Version
<3.5
<10 hrs
Auto K factor > 1.35 sec
2 (1 pilot)
4 (standard config)
6 (high density)
< 400 k
< $100
< $50
0.8
> 20 hrs
< .45
Yes
???
1.43
2
4
5
Yes
Yes
Yes
??
20.5
0.42
< 650 fps
< 600 fps
650
N/A
< 75 dB
< 70 dB
Both VFR & IFR certified
Accommodates both
70
70
Yes
Yes
RD II
ITU LCH Conceptual Design Summary
RFP
Gross Weight
OGE Hover Ceiling
Cruise Speed
Range
Cooper/Harper Rating
Training Time
Very Safe
Cockpit seating
Cabin seating
Acquisition (2002 $)
DOC
Airframe
Maint. Man hr/flt hr
Total System MTBF
EW/GW fraction
External:
MR Tip Speed
TR Tip Speed
Internal
Utility Version
Exec. Version
Daniel P. Schrage
Georgia Tech
Actual
< 4500 lbs
3950
10,000 ft ISA +20 deg
No
> 120 kts
123
>350 (w/20 min reserve
381
RD II
<3.5
<10 hrs
Auto K factor > 1.35 sec
2 (1 pilot)
4 (standard config)
6 (high density)
< 400 k
< $100
< $50
0.8
> 20 hrs
< .45
Yes
???
1.43
2
4
5
Yes
Yes
Yes
??
20.5
0.42
< 650 fps
< 600 fps
650
N/A
< 75 dB
< 70 dB
Both VFR & IFR certified
Accommodates both
70
70
Yes
Yes
at 3650 lbs
from GTPDP
422-reserve
verify with Jeff
from Jeff
assuming 175 lbs ea (total of 8)
get from Rich
get from Rich
get from Rich
get from Rich
get from Rich
verify with Jeff
RD II
GTX-Pegasus Three View Depiction (MD-500E
Derivative – Not ITU LCH Baseline)
Daniel P. Schrage
Georgia Tech
RD II
GTX- Pegasus Isometric Depiction
Daniel P. Schrage
Georgia Tech
RD II
ITU LCH Conceptual Design Status
• The ITU LCH Conceptual Design is nearly
complete and will be by the end of January
2003
• A Product Design Specification (PDS) will
be prepared to document the ITU LCH
Conceptual Design
• The ITU LCH Preliminary Design Effort will
be initiated based on the PDS
Daniel P. Schrage
Georgia Tech
RD II
Proposed approach for conducting the
ITU LCH Preliminary Design effort
• The PD Approach is illustrated in the
following figure and will emphasize the
Product Development (Left Side) process
• Will be conducted jointly by ITU and GIT
Faculty, Research Engineers, Post Docs,
and Students over the next four months
• Will include Monthly In Process Reviews
(IPRs) to review and approve the status
and configuration for the ITU LCH
Daniel P. Schrage
Georgia Tech
ITU LCH Preliminary Design
Approach
Product Development
Requirements Analysis
(RFP)
Baseline Model Selection
(IPPD)
Dynamic Analysis
(DYMORE)
Baseline PDS
Targets
Vehicle Sizing &
Performance
(RF Method)
(GTPDP)
Operations & Support
Processes
Safety Processes
Reliability Modeling
(PRISM, etc.)
Preliminary
Design
ITU LCH
Final Design
Daniel P. Schrage
Georgia Tech
Manufacturing
Processes
Engine Model
Structural Analysis
(NASTRAN)
Stability and Control
Analysis (MATLAB)
Process Development
FAA Certification/
Mil Qualification
CBEM
Geometry/Static Analysis
(CATIA)
RD II
Cost Analysis
(PC Based Cost Model)
Overall Evaluation
Criterion Function
RD II
Planned ASD ITU LCH PD Support
• The following design support activities are planned in conjunction with
the ITU LCH Design Team:
– Development of the Initial Product Design Specification (PDS) –
completed by end of January 2003
– Conceptual Designs for the ITU LCH – Baseline Conceptual
Design completed in GTPDP by end of January 2003, to include
airfoil, blade planform, and baseline engines (turboshaft and
piston/rotary)
– Rotor Airfoil & Blade Planform Trade Study – Complete by 15
February 2003
– Develop DYMORE Dynamic Model of ITU LCH Rotor by 15
February 2003
– Develop a CATIA Model of the ITU LCH by 15 February 2003
– Conduct Stability & Control Analysis for the ITU LCH by 15 March
2003
– Conduct Structures & Dynamics Analysis for the ITU LCH by 15
April 2003
– Finalize the Preliminary Design and Complete & Deliver the ITU
LCH Final Report by 15 May 2003
Daniel P. Schrage
Georgia Tech