DESIGNING ADVANCED
FIGHTER AIRCRAFT
Burt Dicht
Managing Director
ASME Knowledge and
Community Sector
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TODAY’S AGENDA
• Fighter Aircraft Requirements
• The Evolution of Stealth
Technology
• The Advanced Tactical Fighter
• The Design Process
• The Future of Aircraft Design
• Opportunities for ME’s in
Aerospace
• ASME
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MY BACKGROUND
• Currently Director, ASME
Managing Director, Knowledge & Community
• Started out as an ASME student member just like you. A member for 27 years.
• BS Temple University, Philadelphia
• MA, CSUN, Northridge, CA
• Staff of Congressman Jon Fox (PA/13)
• Northrop Grumman – Lead Engineer
T-38 Talon • F-5E/F Tiger II • F-20 Tigershark • YF-23
Advanced Tactical Fighter, F/A-18E/F Super Hornet
• Rockwell Space Systems Division (Boeing)
Space Shuttle Program
• NASA Kennedy Space Center
Summer Intern - Space Shuttle Launch Facility Design
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MODERN FIGHTER
AIRCRAFT REQUIREMENTS
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Air Superiority – controlling the airspace within a limited area and
within a limited length of time
Stealth – seeing the enemy before they see you
Maneuverability – not top speed, but climbing performance,
acceleration and turning speed
Aerodynamics – wing loading – aircraft weight divided by wing area
– one of the most important
Range – ability of the aircraft to reach the combat zone and cover it
Engine – thrust to weight ratio, favorable fuel consumption, low
infrared and smoke
Avionics – Vehicle and systems management, reduced pilot
workload, all weather capability
Armament- kind and quantity of stores on board
Reliability and Maintainability – systems have a high operational
rate and are easy to repair
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THE EVOLUTION OF
STEALTH AIRCRAFT
• From the earliest days,
deception and stealth have
been used to gain the
advantage over an enemy
in combat.
• Early combat aircraft
used camouflage to make
visual detection difficult.
• The advent of RADAR in
the late 1930’s and during
WWII enabled the early
detection of aircraft in
flight.
Romulan “Bird of Prey”
• Equipped with “Cloaking Device.”
• Made the craft invisible to
Federation sensors.
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THE EVOLUTION OF
STEALTH
NORTHROP YB-49 BOMBER
• Designed by Jack Northrop
in the late 1940’s.
• Role was as a strategic
bomber.
• Its unique wing shape
produced a low radar cross
section, although the goal
was improved performance.
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THE EVOLUTION OF
STEALTH
DESIGN IN THE 50’S AND 60’S
• Stealth in aircraft design does
not mean invisible – it means
“Low Observable,” reducing the
radar cross section.
• Little effort in the 50’s and 60’s.
Integrating low observable
aspects meant compromising
performance – so designers
concentrated on speed,
maneuverability, and weapons.
• A-12/SR-71 has rounded lines,
wing/body blending, conical
center bodies, fuselage chine
and canted twin fins to reduce
radar reflectivity.
Lockheed SR-71 Blackbird
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RADAR CROSS SECTION
An object's Radar Cross
Section depends on its
size, reflectivity of its
surface, and the
directivity of the radar
reflection caused by the
object's geometric
shape.
RCS = Geometric cross
section × Reflectivity ×
Directivity
Typical RCS diagram B-26 Invader
(From Wikipedia)
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STEALTH
CHARACTERISTICS
• Airframe shaped for Low
Radar Cross Section
•Use of Radar Absorbent
Material (RAM)
•Minimized engine noise
•Reduced infrared signature
•Reduced visual signature
•Use of electronic
countermeasures
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THE FIRST STEALTH
AIRCRAFT
F-117A Nighthawk
• USAF and DARPA studies
initiated in 1973 – project
Have Blue
•Air Force invites proposals
to develop technology
prototype
•Lockheed and Northrop were
finalists and each built a
prototype for a “fly-off”
•Lockheed wins production
contract in 1976
Mission – covert reconnaissance
and covert surgical strikes
Subsonic – limited performance
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STEALTH GROWS UP
• 1980 report concluded that B-1 bomber would be
unable to penetrate Soviet air space beyond 1990
• Positive results from Have Blue (F-117) justified
launch of a full-scale low-observable bomber
program (Advanced Technology Bomber – ATB)
• Lockheed/Rockwell team and a Northrop/Boeing
team responded to requests for proposals
• Northrop relied on experience studying stealth
technology and its extensive experience with
flying wing designs and was awarded the contract
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STEALTH GROWS UP
NORTHROP – GRUMMAN
B-2 SPIRIT
• Length – 69ft
• Height – 17ft
• Wingspan – 172 ft
• Max Speed – Mach .85
•Range 6300 nm
• Armament – 40,000 lbs in
internal weapons bays
•Powerplant – four GE F-118GE-100 turbofans – 17,300 lbs
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DEVELOPING A TRULY
STEALTH FIGHTER
WHY THE NEED?
• Late 1970’s – Soviets building far more fighters than US
• Massive Soviet surface to air missile threat
• USAF looking to technology to counter Soviet numerical
advantage
• In 1981 USAF issued a Request for Information (RFI) for the
Advanced Tactical Fighter (ATF)
• A RFI does not offer any money or production contracts, it
defines mission, the threat, service entry date and new features
that are desirable and feasible
• Supercruise (the ability to achieve supersonic flight without
afterburner) and stealth were considered essential components,
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although stealth was still considered an exotic technology
DEVELOPING A TRULY
STEALTH FIGHTER
THE ADVANCED TACTICAL FIGHTER (ATF) PROGRAM
• Air Force opts to build a truly air-to-air fighter to follow the F-15
Eagle air superiority fighter - designed to enter service in mid 90’s
• In 1983 USAF issues Request for Proposals (RFP) for ATF and the
Joint Advanced Fighter Engine (JAFE)
• General Electric and Pratt & Whitney vie for engine contract
• Lockheed, Rockwell, Grumman, McDonnell Douglas, General
Dynamics, Boeing and Northrop vie for aircraft contract
• McDonnell Douglas and General Dynamics were thought to have
the inside track because of F-15 and F-16
• But stealth proved to be the deciding factor. Both Northrop and
Lockheed fell back on their stealth experience and proposed
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stealthy fighters that could perform as well as non-stealthy fighters
DEVELOPING A TRULY
STEALTH FIGHTER
THE ADVANCED TACTICAL FIGHTER (ATF) PROGRAM
• In October 1986 the USAF awards the contracts to
build prototype aircraft to Northrop and Lockheed
• Northrop teamed with McDonnell Douglas to build the
YF-23A
• Lockheed - Boeing - General Dynamics comprised the
other team to build the YF-22A.
• Aircraft first flights in the Fall of 1990.
• Lockheed Martin awarded contract in April 1991. The
F-22 is now in production.
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YF-23A BLACK WIDOW II
•Wing Span 43.6 ft
• Two Prototypes were built
•Length
67.4 ft
• PAV 1 - two Pratt & Whitney YF119
engines
•Height
13.9 ft
• PAV 2 - two GE YF120 engines
•Wing area 900 sq. ft.
•Top Speed Mach 2+
•Range
800 Nm
•Altitude
65,000 ft
•Air Superiority
•Low Observable
•Super-cruise - mach
1+ without afterburner
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NORTHROP GRUMMAN
AN AIRFRAME MANUFACTURER
• Responsible for the design,
manufacture and integration of aircraft
and aircraft sub-assemblies
F/A-18 Carrier
Takeoff
Boeing (McDonnell Douglas/Northrop)
F/A-18F Super Hornet
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AIRCRAFT DESIGN PROCESS
• Customer Requirements
• Conceptual Design Phase
General size and configuration of the aircraft •
aerodynamics studies • thrust loading • wing
loading • wing sweep • general body, wing and
tail configurations
• Preliminary Design Phase
Best conceptual design is chosen for testing •
inlet/engine/airframe integration • major loads
and stresses • weight • stability and control •
internal arrangement
• Detailed Design Phase
Configuration frozen • Detailed structural design •
Detailed system design and installation •
Production drawings
• Development Phase
Manufacturing and assembly
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AIRCRAFT ENGINEERING
GROUPS
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Aerodynamics
Advanced Design
Avionics (airborne electronics)
Crew Station (cockpit)
ECS (environmental control system)
Electrical
Flight Test
Fuel Systems
Hydraulic Systems
Propulsion Integration (engines)
Reliability and Maintainability
Safety
Structures
Vehicle Management (flight control)
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CONFIGURATION/
SYSTEMS
INTEGRATION
F-20A Tigershark
• Responsible for overall internal
and external systems
arrangement
• Work with every design group
and coordinate and integrate
their designs into a single
aircraft design
• Final Product:
Inboard Profile Drawing •
Aperture Arrangement • Three
Views • Zone Drawings
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INBOARD PROFILE
F-23A Advanced Tactical Fighter
Profile View
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APERTURE
ARRANGEMENT
YF-23A Prototype Air Vehicle –
Plan View
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AIRCRAFT DESIGN
IS A COMPROMISE
• It is the task of the aircraft design engineer
to balance the customer requirements with
the physical constraints, cost and timescale, in order to produce the most
effective aircraft possible.
• Aircraft Design Requires Teamwork
• No “one” design group is more important
than the others.
• Note: All Engineering involves
Compromises!
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LOOK WHAT HAPPENS WHEN
DESIGN GROUPS HAVE THEIR WAY
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ENGINEERING JOB
DESCRIPTIONS
• Design - From Concept to Production
• Good understanding of engineering principles
• See things in 3-D (Geometry, Graphics, Kinematics)
• Like to solve problems, come up with better ways of doing things
• Analysis - Verify engineering designs (Stress, Thermal,
Aerodynamics, Dynamics)
• Engineering Theory and Mathematics
• Problem solving
• Test - Verify functionality of design
• Basic understanding of engineering theory and design principles
• Lab work and strict guidelines and procedures
• Operations- Maintaining and operating final product
• Basic understanding of engineering design and systems
• Understand how and why things work
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YF-23A BLACK
WIDOW II
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LOCKHEED
MARTIN F-22A
RAPTOR
•Wing Span 44.5 ft
•Length
62 ft 1 in
•Wing area 830 sq. ft.
•Top Speed Mach 2+
•Range
800 Nm
•Altitude
65,000 ft
•Air Superiority
•Low Observable
•Two Pratt & Whitney
F119-PW-100 Turbofans
@ 35,000 lbs
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LOCKHEED MARTIN X-35 (F-35)
JOINT STRIKE FIGHTER
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Bureau of Labor Statistics Aerospace Outlook
Employment Change 2004 - 2014
•Aerospace engineers held about 76,000 jobs in 2004.
•Aerospace engineers are expected to have slower-than-average growth in
employment over the projection period. Although increases in the number and
scope of military aerospace projects likely will generate new jobs, increased
efficiency will limit the number of new jobs in the design and production of
commercial aircraft. Even with slow growth, the employment outlook for
aerospace engineers through 2014 appears favorable: the number of degrees
granted in aerospace engineering declined for many years because of a
perceived lack of opportunities in this field, and, although this trend is reversing,
new graduates continue to be needed to replace aerospace engineers who retire
or leave the occupation for other reasons.
•Mechanical engineers held about 226,000 jobs in 2004.
•Employment of mechanical engineers is projected to grow at an average rate for
all occupations though 2014.
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AEROSPACE & ME
SALARIES
• Average starting salary for Bachelor’s degree
candidates in aerospace engineering is
$53,471 a year. (2006)
• Average starting salary for Bachelor’s degree
candidates in mechanical engineering is
$52,165 a year. (2006)
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THE FUTURE
BOEING 787 DREAMLINER
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THE FUTURE
AIRBUS A380
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THE FUTURE
Northrop Grumman X-47B Pegasus Unmanned Combat Air System
Demonstrator (UCAS-D).
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THE FUTURE
BOEING 797 FLYING WING
PASSENGER JET
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THE FUTURE
SCALED COMPOSITES
SPACESHIP ONE
(Building Spaceship Two for Virgin Galactic)
http://www.scaled.com/index.html
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THE FUTURE
SPACE EXPLORATION TECHNOLOGIES
FALCON 1LAUNCH VEHICLE
http://www.spacex.com
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THE FUTURE
ORION CREW EXPLORATION
VEHICLE
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THE FUTURE
ARES V Launch
Vehicle (two - 5
segment shuttle
SRBs and a 33 ft
diameter liquid
fueled booster
with 5 RS-68
engines for the 1st
stage and an Earth
Departure Stage
with a single J2X
engine)
ARES I
Launch
Vehicle (5
segment
shuttle SRB
for the 1st
stage and a
liquid fueled
J2X engine for
the second
stage)
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THE FUTURE
LUNAR SURFACE ACCESS MODULE
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THE FUTURE
ORION AND LSAM
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AEROSPACE WEB SITES
• Bureau of Labor Statistics
http://www.bls.gov/
• About Aerospace/Aviation - Links to many aerospace
employers
http://aerospace.about.com/industry/aerospace/cs/aviationjobs/index.htm
• SpaceJobs.com - Aviation and Aerospace business news
and job search
http://www.spacejobs.com/index.shtml
• Aircraft Design Sites
http://www.aircraftdesign.com/other.html
• Aerospace Industries Association – sign up for AIA Update
http://www.aia-aerospace.org/
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AEROSPACE WEB SITES
• AOL Hometown - Aerospace Job Search
http://hometown.aol.com/aerojobs/Welcome.html
• Nation Job - Job database and search engine
http://www.nationjob.com/aviation/
• NASA - Job and internship information
http://www.nasajobs.nasa.gov/
http://www.nasajobs.nasa.gov/stud_opps/
• Aerospace Mall - A directory of many aerospace/aviation
related companies (From airframe to suppliers, from military
to general aviation)
http://www.aerospacemall.com/
• Internships
http://www.Tech-Interns.com
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DOING YOUR HOMEWORK
NASA to lose 8,600 jobs with shuttle retirement.
The New York Times (4/2, A24, Leary) reports, "Retiring the space
shuttle in 2010 could result in the loss of 8,000 jobs among NASA
contractors and 600 Civil Service workers at the agency, NASA said
Tuesday." Associate administrator for space operations William
Gerstenmaier said that "the job losses might appear worse than they
would end up," because "a potentially large number of employees could
transfer to new openings developing, building and operating
Constellation spacecraft and rockets." Private companies and retirees
are other areas that might lessen the impact of the job losses. The two
facilities hardest hit would be the Kennedy Space Center (KSC) and the
Michoud Assembly facility, losing 6,400 of 8,000 and 1,300 of 1,900
employees respectively.
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MORE ABOUT THE
AEROSPACE INDUSTRY
ASME’s Professional
Practice Curriculum –
Industry Series
http://professionalpractice.asme.org/
The Aerospace Module:
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Industry Scope
Industry Sectors
Industry Operations
Job Functions
Industry Outlook
Mapping Your Career
Industry Resources
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ASME STUDENT MEMBERSHIP
Founded in 1880 as the American Society of Mechanical Engineers, today ASME
International is a nonprofit educational and technical organization serving a
worldwide membership of 100,000 members and 20,000 student members.
ASME offers students a wide range of technical and non technical benefits that
will enable them to grow professionally, learn about the engineering profession,
and gain valuable skills needed in today;s highly competitive work environment.
Any student enrolled in any curriculum leading to a degree in engineering at a
regionally accredited school is eligible to join. You don’t have to be a Mechanical
Engineering Student.
Dues, $25 per year (10/1 thru 9/30) Freshmen can join for free.
http://www.asme.org/students or call 800-843-2763
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FOR MORE INFORMATION
Burt Dicht, Managing Director
Knowledge and Community Sector
dichtb@asme.org
ASME Headquarters
Three Park Avenue, M/S 23S1
New York, NY 10016
212-591-7074
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