Aeronautical research usually begins with computers, wind

tunnels, and flight simulators, but eventually the theories

must fly. This is when flight research begins, and aircraft are

the primary tools of the trade.

Flight research involves doing precision maneuvers in either a specially built experimental aircraft or an existing production airplane that has been modified. For example, the

AD-1 was a unique airplane made only for flight research,

while the NASA F-18 High Alpha Research Vehicle (HARV)

was a standard fighter aircraft that was transformed into a

one-of-a-kind aircraft as it was fitted with new propulsion

systems, flight controls, and scientific equipment. All research

aircraft are able to perform scientific experiments because

of the onboard instruments that record data about its systems, aerodynamics, and the outside environment.

NASA pilots work closely with engineers to conduct a meticulous flight program that gradually probes an aircraft’s

capabilities: edging toward the speed, altitude, and structural limits that will define the final performance of an aircraft or concept. This procedure furnishes answers that will

verify, extend, and perhaps correct the inputs from computer studies, wind tunnel tests, and simulations. It is the

last step in the development process and leads the way for

designs that can be put into production. It also delivers the

final word on a most crucial question: How well does it fly?

The X-5 for instance, showed that an aircraft can be flown

with moveable wings that can be swept back in flight, a

concept that was later used in many airplanes, such as the

F-111, F-14, and B-1. However, the X-3 demonstrated that

while some of the concepts in its design were successful

(short wings), the combination of short wings, small tail, and

long fuselage did not fly well; aircraft designers took note,

and avoided the X-3’s problems on subsequent short-winged

aircraft.

Experimental research aircraft are tools of exploration, incorporating the newest ideas in every aspect of aerospace

flight, so for this reason they come in many shapes and sizes.

Some have short wings, delta wings, swept wings, movable

wings, and no wings. They fly with jet engines, rocket engines, piston engines, solar-electric engines, and even no

engines. Some research planes are too small to carry a pilot,

while others are as big as airliners. And no matter how radical they seem at first, they contribute to what is eventually

considered conventional.

The first experimental planes designed exclusively for research were the XS-1 and the D-558-1. They were made in

1946 to enable scientists and pilots to study flight near the

speed of sound. Custom-made airplanes were the only means

to accomplish this research because supersonic wind tunnels at the time were not accurate enough, and no other

airplanes had flown that fast. The supersonic era began when

the XS-1 broke the “sound barrier” in 1947.

In the 1950’s the famous “X-Planes” continued to take people

to higher altitudes and greater speeds. They were the first

aircraft to fly Mach 2 and Mach 3, and the studies done with

them influenced the designs of all supersonic planes.

In the early 1960’s, the X-15 rocket plane became the first

aircraft to fly into space. It was one of many aeronautics

projects that supported NASA’s Apollo Lunar Landing Program, but the X-15 was so advanced that it also benefited

the Space Shuttle nearly 15 years later.

Since the 1970’s, NASA flight research has become more

comprehensive, with flights involving everything from Space

Shuttles to ultralights. NASA now flies not only the fastest

airplanes, but some of the slowest. Flying machines continue to evolve with new wing designs, propulsion systems,

and flight controls. As always, a look at today’s experimental research aircraft is a preview of the future.

Aircraft as Research Tools

The NASA Aero-Space Technology Enterprise (AT) is one of

the four NASA Strategic Enterprises established to address

key agency activities in distinctly different areas. The AeroSpace Technology Enterprise's work in science and technology is aimed at sustaining U.S. leadership in civil aeronautics and space transportation. For over 75 years, NASA and

its predecessor, the National Advisory Committee for Aeronautics, have worked closely with U.S. industry, universities, and other Federal agencies to give the U.S. a preeminent position in aeronautics. NASA has expanded this relationship to include aerospace companies, and is now working to revolutionize America's space launch capabilities.

NASA Aero-Space Technology Home Page

http://www.aero-space.nasa.gov/

Aero-Space

Technology Enterprise
1 2 3 45 1. 2.

6 7 8 9 10

11 12 13 14 15

16 17 18 19 20

21 22 23 24 25

26 27 28 29 30

31 32 33 34 35

36 37 38 39 40

41 42 43 44 45

46 47 48 49 50

The front of this poster represents a selection of research

aircraft flown by NASA and its predecessor, the National

Advisory Committee for Aeronautics (NACA). The research

aircraft program began in 1946, and has flown the world’s

most advanced experimental aircraft in research programs

developing the newest concepts in aeronautics. These unique

flight vehicles have influenced the entire spectrum of military and commercial aviation; from hypersonic rocket planes

and solar-powered ultralights, to Space Shuttles and airliners. The following list describes research programs during

the last half of the Twentieth Century. The numbers correspond to the key above.

1946-1956

1. XS-1: Experimental research rocket plane, successfully

designed to break the “sound barrier” and study supersonic

flight.

2. X-2: Swept-wing, rocket-powered aircraft; first to

achieve Mach 3.

3. X-3: Experimental jet explored flying qualities of low

aspect ratio (short) wings.

4. X-4: Small, experimental jet used to study semi-tailless aircraft at transonic (near supersonic) speeds.

5. X-5: Experimental jet; first to verify the concept of

moveable wings that can be swept back while in flight.

6. D-558-1: Experimental jet; developed with the XS-1

to provide some of the first in-flight data on transonic flight.

7. XF-92A: Experimental fighter prototype was America’s

first delta-wing (triangular wing) jet.

8. F-100A: Production fighter jet used in research program that lead to design improvements which solved aircraft’s

dangerous instability problems (inertial coupling).

9. F-101A: Production fighter used in NACA performance

evaluation tests of new armed service aircraft of the 1950s

10. YF-84A: Prototype jet fighter flown to evaluate the use

of “vortex generators” to control airflow over the wings.

Tools of the Trade: Research Aircraft
1956-1966

11. YF-104A: Jet fighter used to develop “reaction controls,” which are small thrusters used for flight control in the

upper atmosphere and space.

12. B-47A: Early jet bomber flown by NACA to study and

improve the design of aircraft with large, swept-back wings.

13. YF-102A: Fighter version of XF-92A used to continue

delta wing research.

14. YF-107A: Fighter prototype used in research program

to develop the first “sidestick” flight control system.

15. X-15: First aircraft capable of hypersonic (Mach 5+)

flight into space.

16. Paresev 1-A: Experimental flight vehicle; first to develop flexible, “parawing” glider concept.

17. A-5A: Bomber used in flight program to determine air

traffic system procedures for future supersonic transport (SST).

18. F5D-1: Navy fighter prototype flown in SST landing

and approach studies.

19. M2-F2: Wingless, experimental research aircraft; first

high-speed, “lifting body” flight vehicle that generated lift

from its body shape instead of wings.

20. LLRV: Experimental Lunar Landing Research Vehicle

(LLRV) simulated lunar spacecraft landings; derivatives became the in-flight trainers used by Apollo astronauts.

1966-1976

21. HL-10: Experimental lifting body; evaluated “inverted

airfoil” body shape for wingless flight vehicles.

22. XB-70A: Experimental Mach 3 bomber used to study

flight characteristics of large, supersonic aircraft.

23. Hyper III: Remotely-piloted experimental aircraft

flown to investigate the use of small, deployable wings for

increasing glide range of lifting body designs.

24. B-57B: Medium bomber modified for research program to study aviation weather such as clear air turbulence

and mountain wave.

25. X-24A: Experimental research aircraft designed to investigate the teardrop lifting body shape for a space vehicle.

26. PA-30-160B: Production airplane modified to develop

remotely-piloted aircraft systems.

27. F-8A SCW: Fighter modified with experimental, supercritical wing (SCW) to improve transonic performance.

28. YF-12A: High-speed reconnaissance aircraft modified

for research and development of navigation and engine systems on Mach 3 aircraft.

29. X-24B: Lifting body research aircraft; as the first lifting

body to land on a conventional runway it proved the feasibility of accurate, unpowered Space Shuttle landings.

30. Firebee: Remotely-piloted aircraft modified for aerodynamic and structural testing.

1976-1986

31. Mini-Sniffer III: Remotely-piloted research vehicle

(RPRV); designed to gather air samples at altitudes of 30,000

m (98,000 ft.), in support of research determining the effects

of jet aircraft exhaust in the upper atmosphere.

32. F-15 SRV: 3/8-scale, F-15 RPRV used as a Spin Research Vehicle (SRV) to evaluate spin characteristics of the

F-15 fighter.

33. KC-135A: Modified air tanker; first transport-size aircraft to use “winglet” wingtip extensions to decrease drag

and improve aircraft performance.

34. Gossamer Albatross: Human-powered aircraft used

by NASA to evaluate aerodynamics of large, light weight

aircraft.

35. F-8B DFBW: Fighter modified to develop the first digital fly-by-wire (DFBW) flight control system.

36. AD-1: Experimental “swing-wing” Ames-Dryden (AD)

research aircraft flown to evaluate concept of wings that

sweep forward and backward in flight.

37. HiMat: Experimental RPRV used to develop Highly

Maneuverable Aircraft Technology (HiMat); design incorporated composites, canards and winglets.

38. B-747 SCA: Airliner modified to serve as Shuttle Carrier Aircraft (SCA); used to ferry Space Shuttles.

39. F-111 MAW: F-111 fighter/bomber modified with a

Mission Adaptive Wing (MAW) that changes shape for flight

control, instead of using flaps and ailerons.

40. F-4C: Fighter modified for wing aerodynamics research.

1986-1999

41. Jetstar: Business jet modified as in-flight simulator to

duplicate flight characteristics of various aircraft.

42. F-15 FRA: Fighter modified for research, Flight Research Aircraft (FRA) was a testbed for new technologies including integrated propulsion/flight controls.

43. PIK-20E: Production sailplane used to establish procedures for collecting sailplane glide performance data.

44. F-18 HARV: Fighter modified for high angle of attack

(extreme nose attitude, or alpha) flight and research; High

Alpha Research Vehicle (HARV) was flown with and without the use of vectored thrust.

45. F-16 AFTI: Fighter modified for use in Advanced

Fighter Technology Integration (AFTI) research program;

voice-actuated controls, digital flight control system and

other advanced technologies evaluated for future fighter aircraft.

46. X-29: Experimental research aircraft incorporated

many new technologies, including forward-swept wings of

composite construction, canards, and triple-redundant

DFBW flight control system.

47. CV-990 LSRA: Airliner modified as Landing Systems

Research Aircraft (LSRA); it was used to test Space Shuttle

landing gear systems.

48. X-31: Experimental research aircraft featured vectored

thrust, and was designed to evaluate technologies that enhance fighter maneuverability.

49. Pathfinder: Experimental solar-powered flying wing

used to develop technologies for future aircraft capable of

high-altitude flights, lasting several days in duration, for environmental research.

50. F-16XL: Prototype fighter modified to research technologies which significantly decrease wing drag at supersonic speeds.
Objectives The students will:

Build a glider.

Learn how to change the flight characteristics of a glider.

Conduct an experiment to answer a question.

Standards and Skills Science

Science as Inquiry

Physical Science

Science and Technology

Mathematics

Measurement

Problem Solving

Science Process Skills

Making Models

Investigating

Predicting

Background The most obvious features of the airplanes on the cover of this poster are the

various wing shapes. The top row of airplanes depicts the first experimental

research aircraft (“X-planes”) flown for the NACA, and each used different wing

and tail configurations to tackle the problems of supersonic flight.

These early jet aircraft had straight wings (X-1), wings that angled (swept) toward

the tail (X-2), triangular (delta) wings (XF-92), and wings that could be moved in

flight to change the angle of backward sweep (X-5). Each design added to our

knowledge of high-speed flight. More recently, aircraft designs have incorporated

wings that sweep forward (X-29), and even wings that sweep forward and

backward at the same time (AD-1 oblique wing aircraft). The X-29 and the X-31

also made use of small wing-like control surfaces called canards which are

located ahead of the main wings.

The templates on this poster allow educators and students to build and experiment with all of these basic wing/tail/canard configurations. Eight different

plastic foam “X-gliders” can be built using these templates (see illustrations, left),

but the total number of variations is only limited by the imagination of the

“designer.”

Materials for building airplanes must be lightweight, strong, and readily available. These qualities make plastic foam a good material for the construction of

flying models. Introduce the X-Glider Activity by discussing with the students

some reasons for using plastic foam in the construction of a model glider. Most

real airplanes are made from another lightweight, strong, and readily available

material called aluminum.

straight wing elliptical wing

swept-back

 wing

swept-forward

wing

delta wing

oblique wing twin fuselage

swept-back

wing

canards
Materials

Plastic foam food tray,

about 28 cm X 23 cm (Size 12)

Cellophane tape

Paper clips

Binder clips

Ball point pen

Plastic knife or scissors

Toothpicks

Goggles (eye protection)

Emery boards or sandpaper

Activity 1. Provide the student with a word list for parts of the glider: fuselage, wing

horizontal stabilizer, canard (see template keys above).

2. Distribute plastic foam trays and copies of the X-glider templates.

3. Ask the student to write the name of each airplane part on the template.

4. Tape the glider template to the food tray.

5. Cut out the airplane parts using the templates. Plastic foam can be cut using

scissors, a razor knife, or a serrated plastic knife. It can also be cut using

a sharp pencil or round toothpick to punch a series of holes approximately

2mm apart around the outside edge of the part. The part can then be pushed

out from the tray. Educators of K-2 students may want to cut out the glider

parts ahead of time.

6. If there are any rough edges around a part, they can be smoothed using

sandpaper or an emery board.

7. Carefully cut a slot in the fuselage. Slide other parts into it to finish the glider

(refer to the X-glider silhouettes for the basic designs; another fuselage is

needed to make the “twin fuselage” glider.)

Extensions 1. An airplane’s weight must be properly balanced for it to fly safely. The same

"weight and balance" principles apply to models. The students can determine the proper weight and balance by attaching a paper clip or binder clip

to the fuselage. Students should vary the position of the clip with each flight

until the glider flies the greatest distance in a straight line. Additional clips

might be needed to improve the glider’s flight performance.

2. Weight and balance is also determined by the position of the wings,

canards, and other surfaces along the fuselage. Have the students move the

wings, stabilizers, and canards to different positions in the fuselage to

determine the settings that make the glider fly best.

3. Have students measure and record the distance of each flight, and compare

the results with each change in the glider’s weight and balance.

Wing

Wing

Horizontal Stabilizer

 Canard or

Horizontal Stabilizer

 Canard or

Horizontal 

Stabilizer

Wing

Wing

Fuselage

Template

keys
X-Glider Template 1
X-Glider Template 2
Basic Aeronautical Terms and Definitions

airfoil: An aerodynamic surface shaped to obtain a

reaction from the air through which it moves; for example,

wing, rudder, aileron, or rotor blade.

aerodynamics: The branch of science that deals with the

motion of air and the forces on bodies moving through the

air.

aeronautics: Word derived from the Greek words for “air”

and “to sail.” It is the study of flight and the operation of

aircraft.

ailerons: Moveable control surfaces forming part of the

trailing edge of the wing that are used to make the airplane roll and bank.

canard: An horizontal stabilizer placed ahead of the wing.

drag: Anything that slows or disrupts the airflow over an

airplane, slowing the plane and opposing thrust.

elevator: A moveable control surface usually attached to

the horizontal stabilizer on the tail that is used to control

pitch (changing the attitude of the aircraft’s nose, making it

move “up” or “down.”)

flight controls: Moveable surfaces on the aircraft that

control its path through the air. The most typical control

surfaces are ailerons, rudders, and elevators.

fuselage: The main structural body of an aircraft to which

the wings, tail unit, etc. are attached.

horizontal stabilizer: Usually a fixed, horizontal tail

surface, but some are designed to move like an elevator.

hypersonic: Speeds of Mach 5 and greater.

lift: The sum of all the aerodynamic forces acting on an

aircraft at right angles to the flight path. Wings create lift.

lifting body: An aircraft that uses the shape of its body to

generate lift instead of using wings.

Mach number: Speed in terms of the speed of sound, i.e.

Mach 1 is the speed of sound.

mountain wave: Wavelike airflow produced on the

downwind side of a mountain as a result of steady, strong

winds blowing over the mountain top.

parawing: A flexible, fabric wing that uses the air pressure

beneath it to form an airfoil that generates lift.

production aircraft: An aircraft type produced in quantity.

Poster credits:

Design, illustration, and text by Ted Huetter.

Program descriptions, glossary, and portions of the

X-Glider Activity edited from NASA sources.

Additional graphics support by Steve Lighthill and

Rod Waid.

This poster may be freely copied and distributed for

educational use.

prototype aircraft: A pre-production aircraft suitable for

complete evaluation of its operating systems and performance.

rudder: A moveable control surface used to provide yaw

(sideways movement), it is usually part of the vertical

stabilizer on an aircraft’s tail.

sailplane: A high-performance glider.

solar-powered aircraft: An aircraft using photovoltaic cells

to convert energy from the sun into electricity to power

electric motors that drive the aircraft.

sound barrier: A nonscientific term referring to the effects

of air pressure upon an aircraft as it attains the speed of

sound. Once believed to be an aerodynamic “barrier”

preventing controlled, supersonic airplane flight.

straight-wing: A wing that is perpendicular to the fuselage.

supercritical wing: A NASA-developed airfoil design that

has relatively low drag at speeds near the speed of sound.

supersonic: Faster than the speed of sound (about 750

mph at sea level).

swept-wing: A wing that has a visibly obvious backward

or forward inclination relative to the fuselage.

thrust: A force that propels an aircraft forward.

transonic: Speeds slightly above and below the speed of

sound.

ultralight: A piloted flight vehicle that weighs less than

140 kg (empty).

vectored thrust: Engine exhaust flow (thrust) that is

directed at angles relative to the aircraft’s fuselage. Thrust

vectoring improves aircraft maneuverability.

vertical stabilizer: A vertical or inclined airfoil, usually at

the aircraft tail or wing tip designed to increase the

aircraft’s directional stability (keep the aircraft moving

“straight ahead”).
On-Line Educational Resources

NASA Education Home Page

The NASA Education Home Page serves as a cybergateway to information regarding educational programs

and services offered by NASA for educators and students

across the United States. This high-level directory of

information provides specific details and points of contact

for all of NASA’s educational efforts, NASA field center

offices, and NASA Regional Educator Resource Centers

located in all 50 States and Puerto Rico.

Educators and students using this site will have access to

an overview of NASA’s educational programs and services,

along with a searchable program inventory of NASA’s

educational programs.

NASA EDUCATION HOME PAGE:

http://education.nasa.gov

NASA Spacelink and Spacelink Express

NASA Spacelink is a “virtual library” in which local files

and hundreds of NASA World Wide Web links are arranged in a manner familiar to educators. Spacelink is one

of NASA’s electronic resources specifically developed for

the educational community.

Spacelink is the official home of electronic versions of

NASA’s education products. NASA educator guides,

educational briefs, lithographs, and other materials are

cross-referenced throughout Spacelink with related topics

and events. “Hard copies” of NASA education products

may be ordered directly through NASA Central Operation

of Resources for Educators (CORE). Spacelink is also host

to the NASA Television Education File schedule.

SPACELINK HOME PAGE:

http://spacelink.nasa.gov

NASA CORE:

http://spacelink.nasa.gov/CORE

Educators can learn about new NASA educational products by subscribing to Spacelink EXPRESS. Spacelink

EXPRESS is an electronic mailing list that informs subscribers by e-mail when new NASA educational publications

become available on Spacelink.

SPACELINK EXPRESS HOME PAGE:

http://spacelink.nasa.gov/xh/express.html

NASA’s Learning Technologies Project (LTP)

NASA’s Learning Technologies Project (LTP) is an agency

asset that includes a suite of Internet projects that teachers

and students can use to explore NASA resources and learn

about NASA missions.

LTP offers a wide variety of educationally sound, standards-based projects that help educators explore science,

math, and engineering from the classroom. LTP also

supplies information on integrating technology into the

classroom, and on grant opportunities.

Through “Sharing NASA” (interactive projects available

from LTP’s Quest server) and the Learning Technologies

Channel (LTC) educators and students can participate in

events via a multidimensional web experience. E-mail,

chat rooms, audio, video, text transcription, and sometimes NASA Television are employed to take participants

to workshops, lectures, seminars, courses, and exciting

live events around the world.

LTP HOME PAGE:

http://learn.ivv.nasa.gov/

EDUCATION PROJECTS FROM LTP:

http://learn.ivv.nasa.gov/education/topics/

education.html

For Learning Technologies Channel information,

e-mail:

listmanager@quest.arc.nasa.gov

NASA Aero-Space Technology

Education Home Page Websites

NASA AMES RESEARCH CENTER

http://george.arc.nasa.gov/dx/basket/storiesetc/

Edprogsa.html

NASA DRYDEN FLIGHT RESEARCH CENTER

http://dfrc.nasa.gov/trc/

NASA LANGLEY RESEARCH CENTER

http://edu.larc.nasa.gov/

NASA GLENN RESEARCH CENTER

http://www.grc.nasa.gov/Doc/educatn.htm

NASA MARSHALL SPACE FLIGHT CENTER

http://www1.msfc.nasa.gov/education/

NASA Aeronautics Photographs and Images:

NASA Image eXchange (NIX) is a web-based tool for

simultaneously searching several NASA image archives on

the Internet. NIX searches databases of over 300,000 online NASA images.

http://nix.nasa.gov/

NASA Dryden Flight Research Center Gallery offers

photographs and movies depicting NACA and NASA

research aircraft including each airplane on this poster.

http://www.dfrc.nasa.gov/gallery/photo/

EW-1999-03-001-DFRC

Please take a moment to evaluate this product at

http://ehb2.gsfc.nasa.gov/edcats/educational_wallsheet

Your evaluation and suggestions are vital to continually

improving NASA educational materials. Thank you.