The X-15 Research Airplane

5 ¥- 1 tS R EE S R

E

A

B

C

B

AIRPLANE

=---=-----=

N A S A test pilot Joseph A. Walker (right) heads for the X-15, which is hooked under the right right wing wing of the big 8 - 5 2 mother plane. under the

THE IT

15 RESEARCH AIRPLANE

to zero in an X-15 countdown that be hours ago. Tucked under the right wing of 52 aircraft, the X I5 is about 45,000 ee eett above Mu Lake Nev. Th I5 pilot i making his final check MINUTE

IS

ga

X-1S RESEARCH AIRPLANE

24

out: At

minute "Prime switch to PRIME."

At 40 s e c o n d s "Precool switch to PRECOOL." "Igniter idle ON

DESIGN M A X I M U M VELOCITY 4 , 0 0 0 MP DESIGN ALTITUDE - 47 MILES

At 10 seconds-

"Pump idle ON At

STRUCTURAL TEMPERATURE TO REACH STRUCTURAL DEGREES FAHRENHEIT

seconds"Launch light ON

pilot moves the mast master er arming switch to ON Th X-I5 pilot is in his radio countdown:

Th

-5

3

-I-LAUNCH!"

AIRCRAFT WEIGHT, LB LAUNCH 3 3 , 0 0 0 --22.6

LANDING 14,700

The 8-52 in flight with

he three hooks that support th X-15 open. X-IS drops rapidly away. Th X-15 pilot opens the throttle of the 57,000pound-thrust rocket engine. He pulls back th stick. In an 84-second surge of power reaching more than 500,000 horsepower, th X-15 accelerates from 600 to more than 4,000 miles an hour, an climbs steeply to 150,000 feet. Th fuel gone now, momentum drives th aircraft in ballistic arc up to 314,750 feet (more than 59 miles), above all bu minute trace of th earth's atmosphere. Th sky shades to dark blue. Th pilot sees th horizon a a curve, an ca make ou in one sweeping glance Monterey Bay an part of the Gulf of California, which ar some 500 ground miles apart. Th

X-15 under its wing.

As the X-15 continues on its ballistic path, th pilot becomes weightless. This experience contrasts sharply with what he felt when the engine was still firing an he was pressed hard into his seat by th force of 6G. With little atmosphere surrounding the craft, he

knows its conventional aerodynamic controls have no effect. So he us uses es the h ydrogen peroxide jets set in th nose an wings. point the downward, for ex ample, he uses the jets on top of th nose. He maneu vers th X-15 in th near vacuum of space where no conventional airplane could fly. Ahead lies a critical part of his flight mission-reentry into the earth's atmosphere. Any object entering this atmosphere from space at high speed is subjected to ai

friction, acceleration, an dynamic pressure that build up tr emendous heat. Th X - 1 S outer structure is made of Inconel X, nickel-steel alloy that withstands tem peratures up to 1,200 F. But entry heating could ex ceed that temperature, an the combination of thermal an ai load might cause some structural failure unless it escende precisely along a predetermined path. As the black craft pierces increasingly thicker atmos ph ere, its st ub y wings grow dull cherry re an its struc-

ture pops like a ho

stove. Gra vit y forces becomes so stove. movement of th center great that th pilot finds ar control stick extremely difficult, an he keeps th plane on course with a hand- an wrist-controlled side stick. Despite the extreme heat on th outer skin, tempera tures in the pilot's cabin an the instrument compart ment remain comfortable. This condition is the result of a specially constructed system in which liquid nitro ge at 300 below zero F. is used.

The X-1S drops free.

MAX DYNAMIC PRESSURE (THAT IS PRESSURE CAUSED BY

CLIMB

ANGLE 35

MOVEMENT THROUGH THE ATMOSPHERE) 00

lBS

PER SO

fT

Flight profile of

the

X-1S.

As atmospheric density increases, the pilot again uses aerodynamic cont controls. rols. Sometimes here he also uses th hydrogen peroxide je system Ahead, he sees his landing field, the flat expanse of Rogers Dr Lake at Edwards, Calif., some 200 miles from th starting point of his launch To slow th plane, he opens speed brakes near the tail. About miles from touchdown, he jettisons the ventral fin ex tending under the tail (this fin has contributed to sta bility during high-speed flight bu would interfere with landing) an lowe lowers rs hi landin g e a r - a conventional nose wheel an two steel skids toward th rear. Th pilot touches down at about 210 miles an hour. He lands nose high, the skids hitting the ground first, bu almost immediately th nose gear touches. Th plane comes to a stop almost a mile across th lake bed from the touchdown point. Besides breaking world speed an altitude records for aircraft, th rocket-powered X-15 has also already sur passed its own design speed of 4,000 m.p.h. an design altitude of 250,000 feet. has flown faster than 4,100 m.p.h. an higher than 314,000 feet-and it can be ex pected to go higher. Bu th setting of speed an altitude records is no the real purpose of th X-IS. Th program procedure followed has been generally to increase the speed an th altitude of flights on an "incremental performance" basis T h a t is, flights were designed to reach increas ingly higher speeds or altitudes to permit the taking of practical-size "bites" of data on the hypersoni environ-

714 90 0

63

ment while building

fund of increasing pilot experi

ence. Part airplane, part spacecraft, th X-IS is th only vehicle of its kind in the world. It is 50 feet long, 22.6 feet wide, an 13 feet high. It is a winged vehicle con trolled by pilot on board. Intended solely for re search, it serves as a proving vehicle for theories de veloped by such techniques as mathematical computa tions an wind tunnel tests.

X-15 Until produced much mation needed in designing high-altitude hypersonic Skids down, nose up, fuel spent, the X - 1 5 streaks in for a dr lake be landing.

operational aircraft.

They have provided a great

amount of data on the physiological an

psychological reactions of me to space Right an to th piloting of high-speed, high-altitude aircraft. They have helped tremendously in space sciences programs. Th pilot plays the key role in every X-15 flight. He no only carries out the programmed tests bu also uses his judgment an experience in solving unantici pated problems. His observation and judgment add to, interpret, an enrich th data gathered by the plane's research instruments. Ho do we ge information from X-15 flights? What kind of information is it? During each flight, instruments in the airplane an inside the pilot's pressure suit transmit to ground sta tions constant stream of data on aircraft operation an physiological ogical condition Data on the X-15 th pilot's physiol includ readings on aerodynamic heating an stress on structure, powerplant behavior electrical system opera tion, stability, an control. Pilot checks cover such measureme measu rements nts as heart action, bod body y temperature, r adia tion, respiration, an pulse. Th pilot's own observa tions supplement an clari clarify fy instrument data. Infor mation from each flight is completely documented for later analysis. Three gro un radar stations-at Ely an Beatty, Nev an Edwards, Calif.-receive the flight data. Th X-15 is always within range of at least one of these stations. At th NASA Flight Research Center Radio Station, Edwards Ai Force Base, research engineers closely

Painted by Robert W. Copyright 1962, National Geographic Society Nicholson, Staff Artist. Reproduced by Special Permissi n.

watch aircraft performance, and a physician checks anything seems amiss, the pilot is data on the pilot.

notified an alternate procedures are recommended. Thus, in a sense, skilled research engineers an a capable flight surgeon accompany the X - I S pilot on every mISSIOn.

This is one of many measures to assure pilot safety His instrume nt panel al also so alerts him to to danger. Green that everything lights tell hi working right. green light winks off an harsh orange ligh t comes comes on, the pilot at once knows what is wrong an ca ac ac cordingly. Fo example, an orange light warns him that pressure at the fuel pump is too low to run the en gine at full thrust Appropriate action: the pilot re duces thrust. Th pilot's pressure suit inflates automatically if cock pi pressure fail fails. s. This suit has its own atmo sphe re an in effect becomes a pressurized cabin. In extreme emergency, a rocket powered ejection seat would hurl th pilot free of the a i r p l a n e - a t speeds up to four times that of sound Folding fins an telescopic booms prevent dangerous tumbling during catapult and stabilize th seat. At a safe altitude, a timer would open the pilot's parachute and relea release se the seat Safety factors were high among th considerations that determined locating the X-15 High Range (flight corridor), which stretches across across the Moja ve Desert be tween Wendover, Utah, an Edwards, Calif Calif.. This area is dotted with many level dry lake beds, in reach for emergency landings.

A careful step-by-step program has been followed in bringing the X-15 safely up to design performance. plane was first first airlifte d in "captive" fligh flights ts in whic it did not separate from the B-52. Then came a power less glide flight to check control an landing, an finally th powered flights at gradually increased speeds an altitudes. Since June 1959, when the first planned glide flight was made, 74 flights have re ulted from 126 attempts. Pilot Walker being zipped into his inner flight suit, which will air-condition him and protect him against G forces and decompression.

("Attempt" here means any case when th

carry ing th X - I S goes aloft an an X - I S drop is intended.) flights have been m?-de by seven pilots-three civilian NASA research pilots, two Ai Force pilots, one Navy pilot an one commercial pilot during contractor demonst ra ion trials. In a "follow-on" research program announced by NASA in April 1962, the X-IS assumed an additional role as a "service" airplane for carrying out new experi ments in aeronautical an space sciences. This pro gram is based on X - I S capacity for extremely high speeds an for altitudes beyond the earth's atmosphere. To get maximum information from each flight, data for some of the new studies will be gathered during flights already scheduled. Th IS will carry addi tional equipment for that purpose On new project on which work began at once was an experiment in ultraviolet stellar photography. earth and at the lower altitudes ultraviolet rays of th stars are obscured by ozone in the earth's atmosphere. Th Orbiting Astronomical Observatory (OAO), one of NASA's major projects is designed to take stellar photographs as it orbits th earth far above the dis torting atmosp atmosphere. here. Th IS mission includes a sup porting role in th stellar photography program as forerunner of OA an as a flying test bed to check ou the kind of equipment used in OAO. No planned is a series of X - I S stellar photographic flights to alti tudes above 40 miles, to supplement OA work in study of the origin an composition of the stars. B-S2

On

important advantage sought in th

new

X-IS

project is th pilot's ability to orient the aircraft with respect to the stars above th ozone layer an th capa bility of the aircraft to return to that altitude an repeat the experiment. Fo these flights, new instrumentation has been in stalled in the X 15. It consists of a platform with four cameras, mounted in the instrument bay behind the pilot's cockp cockpit. it. Clamshell doors covering the bay can be opened by a cockpit control as the X-15 leav es the atmosphere. Th pilot then maneuvers th X-IS into the right position to photograph target star. As th plane follows its ballistic trajectory "over th top," th cameras ca take a continuous series of photographs in different ultraviolet wavelengths. Photographs have been b een taken in the past from sound ing rockets, but the spinning action these rockets require for stabilization usually prevents precise orientation for selected targets Occasionally, too th photo infor mation is lost when the payload is not recovered after th shot. By a similar method, horizon scanner studies light across the spectrum Th object here is to gather in formation on means of accurate sensing an to develop improved attitude and uidance references for earth orbiting spacecraft. An alphatron ionization gauge mounted in a small wingtip pod measures atmosphe re density above 100 100,000 ,000 feet. A similar pod houses equipment for measuring micrometeorites. In several other experiments infrared

untraviolt data at the extremes of the X-IS's higher altitude capability will be investigated. Th program also includes evaluation of advanced vehicle systems an structural materials. An electric stick stic k c ontroller will be tested for possible application in manned spacecraft. Th X-1S is the harvest of ideas an work extending over the last decade. In Ma 1952 the National Adan

visory Committee for Aeronautics (NACA), which later formed the nucleus of the National Aeronautics an Space Administration (NASA), directed its labora tories to begin studies of manned hyper onic flight at high altitudes. In Ma 1954, NACA established per formance requirements for research craft that would assist in these studies.

Technicians assist Maj. Robert A. Rushworth with

his

helmet after an X-15 flight.

1960

In July 1954, representatives of NACA, th e Air Force,

th Navy agreed on joint research airp an pro gram. In November 1955, North American Aviation, Inc., was awarded etter contract to build the three X-15 airplanes. Subsequent important developments in th program were: an

1957 Contractor completed building first X-1S.

SEPTEMBER

studi st udi es,

OCTOBER: First X-1S completed, delivered for gro un

tive" flight of X-IS (p la re mained attached to -S carrier craft during entire flight) .

First "c

1959 UNE

1961 FEBRUARY: Contractor

elivered to Government first X-IS powered by XLR99 engine.

1961 NOVEMBER: Maj. Robert White, U.S. Air Force pilot

flew X-IS at 4,093 m.p.h., achieving design speed of th airplane.

1962

ase, Calif.

1959 MARCH:

XLR99 57,000-pound-thrust engme.

began

1958 tests to Edwards Air A ir Force

NOVEMBER: Contractor flight-tested X-15 with final

APR IL: Jo se ph A. Walker, NASA pilot, flew X-1S to

altit ud

of 246,700 feet, achieving design altit altitud ud e. 1962

UNE : Pilot Walker flew X-IS

passing all

revious speeds.

1962

First lid flight of X-IS. 1959

First powered flight, with two interim engines generating 16,000 pounds thrust.

SEPTEMBER

JULY: Pilot White flew X-IS to an altitude of 314,7S0 feet, qualifying himself as an "astronaut ," NASA an military designation for pilots who have made flights above SO mil es in altitude.

1960 FEBRUARY: Contractor, after suc successfu cessfull ll

10

completing flight tests, delivered firs X-IS to NASA, Air Force, an Navy.

4,104 m.p.h., sur

Future

platform for conducting scientific X-IS is used as experiments at high altitudes an hypersonic eeds on a repeatable basis.

The X-1S pilots: (begin lower left and clockwise) Maj. Robert A. Rushworth, USAF; Maj. Robert M. White, USAF; Milton O. Thompson, NASA; Joseph A. Walker, NASA; and John B. McKay, NASA.

11

X-15 Flight Number

Date

1-1-5 2-1-3 2-2-6 2-3-9

8-59 9-17-59 10-17-59 11 5-59 1-23-60 2-11-60 2 - 1 7 ~ 0 

3-17-60 3 - 2 5 ~ 0 

3-29-60 3-31-60 4 - 1 3 ~ 0 

4-19-60 5- 6-60 5-12-60 5 - 1 9 ~ 0 

5

-

2

~

0



4-60 8-12-60 8-19-60 9 - 1 0 ~ 0  9 - 2 3 ~ 0 

10-20-60 1 0 - 2 8 ~ 0 

11 4-60 11-15-60 11-17-60 11-22-60 1

1

-

3

12 12

~

0



6-60 9

~

0



1-61 7 ~ 1 

7-61 3

-

3

~

1



4-21-61 5-25-61

12

6-23-61 8

-

1

See

~

1



fo otn

1-2-7 2-4-11 2-5-12 2-6-13 1-3-8 2-7-15 2-8-16 1-4-9 1-5-10 1-6-11 1-7-12 1-8-13 2-9-18 1-9-17 1-10-19 1-11-21 1-12-23 1-13-25 1-14-27 1-15-28 1-16-29 2-10-21 1-17-30 2-11-22 1-18-31 2-12-23 1-19-32 1-20-35 1-21-36 2-13-26 2-14-28 2-15-29 2-16-31 2-17-33 1-22-37 nd of ta bl ble. e.

Pilot Crossfield

FLIGHT LO

--Speed-Mach No

52

37 550

Planned glide flight.

1 393

First

15

1,419

52,341 61 781

66

45,462

Engine fire landing

79

53

Crossfield

22

1,466

57

036 41 32

15 00 96

293

340

Walker

56

68

48 00 59,496

White

20 19

1,452

60,938

111

31

1,590 1,452 19 77

77 882 108,997 51,282 78,112

20

Walker

31

White Walker

52 3.13

White

23

Petersen

68

McKay

Rushworth Crossfield Rushworth Crossfield Armstrong Crossfield Armstrong

94 02 1.95 2.97 90 51

1 75 2.85 80

98 2,182 108 280 1,333 282 960 1,254 65 1,155

1,881

13

81 20

54,750

90 48 840

61

53 37

White

95 62 90 27

074 30 60

Petersen

11

735

78,200

Walker

76

restart w th XLR99 design engine

50,700 48 90

2,905

White

First

53 800

50 4.43

Walker

flight with XLR99 design engine

79 864 53 04

50 09 49 78 78 15 77,450 16 60 105,000 10 500 10 70

275

First

500

88

White

Govt. flight.

75 98

188 24

McKay

First

49,982 51,356

255

White Crossfield

fuselage structural failure on

52 64 48 63

94

Walker

powered flight

66 84 88 11 42 64

03

White

Remarks

2.11 1.00

Walker

Maximum Altitud (in feet)

Last LR11 flight First Govt XLR99 flight.

S. GOVERNMENT PRINTING OFFICE

1963

671490

X-1S FLIGHT LOG-Continued Date

9-12-61 9-28-61

10

4-61 10-11-61 10-17-61

11

9-61 12-20-61

1-10-62 1-17-62 5-62 4-19-62 4-20-62 4-30-62 5- 8-62 5-22-62 1-62 7-62 6-12-62 6-21-62 6-27-62 6-29-62 7-16-62 7-17-62 7-19-62 7-26-62 8- 2-62 8- 8-62 8-14-62 8-20-62 8-29-62 9-28-62 4-62 10 9-62 10-23-62 11 9-62

Flight Number

Pilot

Altitude

3,614

30 30

3,600

White Armslrong Petersen

6.04

2,830 3,647 3,900 4,093

76

2,502

101,600 81 00

97

645

44,750

3,765

133,500 179,000 154,000

3-2-3 3-3-7 1-26-46 31-27-48 2-22-40 1-28-49 2-23-43 1-29-50 3-5-9 3-6-10

Armstrong

21

74

51

Walker

06 5.69

2,830 866

Armstrong

5

94 34

3,789 3,489 524

Walker

Rushworth

31

Remarks

(in feet)

5.25

Walker

3-8-16 2-26-46 3-9-18 2-27-47 2-28-48

Maximum

Petersen Rushworth White

2-18-34 19-35 1-23-39 2-20-36 1-24-40 2-21-37 3-1-2 1-25-44

2-24-44 1-31-52 3-7-12 2-25-45 1-32-53

--Speed-H. Mach No. M

114,300 100,800 78,000 217,000 108,600

207,500 246,700

Flight made wilh lower ventral

Design speed achieved First flight for X-15 N o . 3 Emergency landing on Mud engine failed to light

5.03

3,450

White

5.42

3,675

Walker

5.39

3,672

103,600

02

3,517

184,600

5.08

3,641

246,700

92

4,105

123,700

Highest speed achieved

95 5.48

83,200 107,000 314,750

FAI world alt. record

84,500 100,000 107,000

Walker McKay

White

04

3,280 3,733 3,784

McKay

11

375

82

3,954 3,443

Walker

Armstrong Walker Rushworth Walker

4.99 39

5.13 22

2,898 3,784

2-29-50

McKay

4.08

3,443 3,443 2,693

3-10-19 2-30-51 3-11-20 2-31-53

Rushworth

4

91

3,375

38

3,716 81 62

Rushworth

21

McKay

Rushworth McKay

5.57

.95

Flight Fli ght aclivity co de: First number is X-15 airplane number Third number is X-15 B-52 airborne mission number.

Lake afte

Design alt. flight.

70,400 100,400 132,600

White

off.

Outer panel of left windshield cracked

90,000 197,000 87 00 97,000

67,000 106,000 129,000 134,000 45,200

Emergency landing on Rogers Dry Lake after engine power failure. Plane badl damaged by skid

Second number

is

flight number

for

lhe specified airplane

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