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For educational purposes
The North American Aviation XB-70 Valkyrie is the prototype of the B-70 nuclear-armed, deep-penetration strategic bomber for the U.S. Air Force's Strategic Air Command.
North American Aviation designed the Valkyrie bomber as a large, six-engined aircraft capable of reaching Mach 3+ while flying at 70,000 feet (21,000 m).
At these speeds, it was expected that the B-70 would be almost immune to interceptor aircraft, the only effective weapon against bomber aircraft at the time.
The bomber would spend only a few minutes over a particular radar station, flying out of its range before the controllers could position their fighters in a suitable location for an interception.
Its high speed also made the aircraft difficult to see on the radar displays, and its high altitude flight could not be matched by any contemporary Soviet fighter.
The introduction of the first Soviet surface-to-air missiles in the late 1950s put the near-invulnerability of the B-70 in doubt.
In response, the US Air Force began flying its missions at low level, where the missile radar's line of sight was limited by local terrain, in this low-level penetration role, the B-70 offered little additional performance over the B-52 it was meant to replace.
It was, however, far more expensive and had shorter range. Other alternate missions were proposed, but these were of limited scope.
As the strategic role passed from bombers to intercontinental ballistic missiles (ICBMs) during the late 1950s, manned bombers were increasingly seen as obsolete.
The USAF eventually gave up fighting for its production, and the B-70 program was canceled in 1961.
Development was then turned over to a research program to study the effects of long-duration high-speed flight, as such, two prototype aircraft were built, and designated XB-70A; these aircraft were used for supersonic test-flights during 1964–69.
In 1966, one prototype crashed after colliding in mid-air with a smaller jet aircraft; the remaining Valkyrie bomber is in the National Museum of the United States Air Force near Dayton, Ohio.
The North American Aviation XB-70 Valkyrie is the prototype of the B-70 nuclear-armed, deep-penetration strategic bomber for the U.S. Air Force's Strategic Air Command.
North American Aviation designed the Valkyrie bomber as a large, six-engined aircraft capable of reaching Mach 3+ while flying at 70,000 feet (21,000 m).
At these speeds, it was expected that the B-70 would be almost immune to interceptor aircraft, the only effective weapon against bomber aircraft at the time.
The bomber would spend only a few minutes over a particular radar station, flying out of its range before the controllers could position their fighters in a suitable location for an interception.
Its high speed also made the aircraft difficult to see on the radar displays, and its high altitude flight could not be matched by any contemporary Soviet fighter.
The introduction of the first Soviet surface-to-air missiles in the late 1950s put the near-invulnerability of the B-70 in doubt.
In response, the US Air Force began flying its missions at low level, where the missile radar's line of sight was limited by local terrain, in this low-level penetration role, the B-70 offered little additional performance over the B-52 it was meant to replace.
It was, however, far more expensive and had shorter range. Other alternate missions were proposed, but these were of limited scope.
As the strategic role passed from bombers to intercontinental ballistic missiles (ICBMs) during the late 1950s, manned bombers were increasingly seen as obsolete.
The USAF eventually gave up fighting for its production, and the B-70 program was canceled in 1961.
Development was then turned over to a research program to study the effects of long-duration high-speed flight, as such, two prototype aircraft were built, and designated XB-70A; these aircraft were used for supersonic test-flights during 1964–69.
In 1966, one prototype crashed after colliding in mid-air with a smaller jet aircraft; the remaining Valkyrie bomber is in the National Museum of the United States Air Force near Dayton, Ohio.
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LearningTranscript
00:30Take off with the Discovery Channel in the XB-70 Valkyrie.
00:34More than a quarter century after its maiden flight, the XB-70 stands as one of aviation's greatest achievements.
00:41Designed as a replacement for the Boeing B-52, the XB-70 could travel at three times the speed of sound.
00:48Employing technology that was well ahead of its time, the XB-70 is one of the best aircraft designs that never went into production.
00:56Tonight, soar high in the XB-70 Valkyrie on wings.
00:59This is the XB-70 Valkyrie, a supersonic heavy bomber that featured design innovations decades ahead of the planes of its time.
01:15Yet this revolutionary aircraft never went into service, because while it was being developed, the strategic picture changed.
01:22A decade later, a similar fate almost befell this plane, the B-1 bomber.
01:30Apart from modifications to the engine intake, the B-1B seen here looks very similar to its controversial predecessor, the B-1A heavy bomber.
01:39However, because of the evolution of technology, the B-1B, in many ways, was a very different aircraft.
01:46Like the XB-70, the B-1A was designed to replace the B-52 as the Strategic Air Command's high-altitude heavy bomber.
02:06However, due to political conflicts and technical problems, the project was canceled.
02:13But the B-1 didn't die.
02:15Over the next several years, the U.S. Air Force and Rockwell, the plane's manufacturer, revised the aircraft's parameters.
02:24Taking full advantage of the aircraft's swing-wing potential, Rockwell redesigned the plane for the long-range, low-level mission.
02:31The plane was outfitted with the latest detection-evasion electronics.
02:42But the major difference between the B-1A and the B-1B is simply that the later model,
02:49although the product of considerable technical innovation and years of additional development,
02:54was actually made to be slower than its predecessor.
03:01Radar jamming and stealth technology have changed the specifications for strategic bombing aircraft.
03:08But this is a relatively new development.
03:11For much of the century, the military constantly sought faster and faster planes.
03:17Probably the biggest single step forward in the search for new technology to gain higher speed
03:22came with the advent of the jet engine.
03:24Although pre-war Germany first utilized jet power,
03:32American engineers also tested the concept on experimental aircraft before the war's end,
03:37with aircraft like Bell's Aero Comet.
03:39The first major development of the post-war years was the record-breaking Bell X-1 rocket-powered experimental aircraft.
04:04Dropped from a Second World War bomber on December 9, 1946,
04:16in the hands of test pilot Chuck Yeager,
04:18the X-1 broke the sound barrier for the first time.
04:22Further development produced the X-2,
04:25which flew faster and higher than its predecessor.
04:27We'll see you next time.
04:58The quest for higher speed put phenomenal stress not only on aircraft,
05:02but also on their pilots.
05:04The risk of even a minor malfunction at the speeds now being attempted was enormous.
05:09Much of the data gathered by the X-airplane tests was used for military objectives.
05:32Faster aircraft would be harder targets to hit.
05:35The X-airplane tests were used to hit against each other.
05:39However it would make the X-airplane tests were used to hit.
05:40People from the past few years from now being attempted to hit.
05:42But, the X-airplane tests were always directed at the X-airplane tests were manipulated at the X-airplaneス.
05:44It was re-medical and changed its first time as the X-airplane test was developed.
05:44The X-airplane tests were assigned to ride also on aircraft-add 나왔 at the X-airplane launch hour in its rear-flijke.
05:46Therefore, the X-airplane tests¥ à 총et is about the X-airplane test.
05:49The X-airplane test was used for the X-airplane test.
05:50The X-airplane test was forced to hit.
05:51The X-airplane test was used for the X-airplane test is a new aircraft-OWN plan nitrogen-ulu engine,
06:23Some of the lessons learned from the X airplane program were applied to American fighters and bombers. With the Cold War on, stretching the boundaries of speed and distance had become a matter of national security.
11:20This offered strength and dissipated heat.
11:27After 12 months of testing designs and mock-ups, an order was placed for one XB-70.
11:33But the aircraft, now called Valkyrie, was in for a stormy time.
11:43Two years after accepting the concept,
11:45financial pressures forced the Air Force to limit the production to one prototype.
11:50Although extra money was made available in 1960,
11:54the Air Force was having trouble holding on to its supersonic bomber.
12:01The final blow came with the arrival of Secretary of Defense Robert McNamara,
12:05who redefined the XB-70 as a high-speed research project
12:09and limited production to just two aircraft.
12:15But at least the concept was still alive,
12:18and its proponents hoped it still might ultimately be accepted for military use.
12:23By 1963, at least one aircraft was well underway.
12:28The first XB-70, serial number 2001, must have been an awe-inspiring sight for those lucky enough to see it.
12:46But it was not until May 11, 1964, that the press and public were given their chance to marvel over North America's sleek white wonder.
12:58Brigadier General Fred J. Ascani, who directed the B-70 System Program Office, described the plane's various features.
13:13Most of the structure in the wings and fuselage is of stainless steel.
13:19These are our now-famous honeycomb core sandwich panels.
13:23And many of the outer skins on these honeycomb panels are as thin as seven one thousandths of an inch.
13:30The two-man crew will sit side by side.
13:37The crew station in this position is about twenty feet above the ground.
13:42All of the space aft of the crew compartment is taken up by fuel, both in the fuselage and in the wings.
13:51Before the XB-70 was poised at the downwind end of Palmdale's twelve thousand foot runway for its first flight,
13:59numerous ground tests would have to be performed.
14:02Shortly after its debut to the public, the aircraft was again up on jacks,
14:07while its electrical and hydraulic support systems were thoroughly tested.
14:11All moving surfaces were subjected to vigorous testing.
14:21All flight controls, including the forward canards, the elevons and rudders, were fail-tested and tested again.
14:31This vertical Luckily, even if you don't fallidas too first,
14:47But you can also know where however manyans might now be faktor-tested in theさい,
14:52An unrel Athor's switch is a elementary track model.
14:55The blue can now be taken off from the coordinates without creating a aventure from a gitti상 that they would have been independent.
15:00Like so much of the XB-70, the landing gear, which had to support the plane's phenomenal
15:14weight, as well as the added stress of landing and takeoff, was, for the time, a unique and
15:20brilliantly designed feature.
15:30The forward twin wheels were conventional.
15:57But the support gear was required to rotate as well as fold the four-wheel bogey mechanism,
16:02which was stored in the limited space available.
16:05The whole process of extending or retracting the clever but complex gear could be achieved
16:10in a little over 20 seconds.
16:23All of the many complex tests that took place during the weeks before the first takeoff
16:28were recorded in a special flight test instrumentation package.
16:32A self-contained airborne unit, this device was the first of its kind.
16:37It was carried in the aircraft's bomb bay and remained with the plane for ground taxiing
16:42and in-flight tests.
16:58The XB-70 prototype was also subjected to vibration tests that were designed to expose the gigantic
17:04fuselage and wing surfaces to the effects of vibration far beyond the point it might encounter
17:09in flight.
17:27As the aircraft tests proceeded, air crews were introduced to some of the engine's characteristics.
17:32Here, at the Arnold Engineering Development Center in Tennessee, a YJ-93 engine was set up
17:39in a simulation of the Valkyrie.
17:41The engine was installed in a test chamber to give the flight crew their first experience
17:46with its enormous power.
17:48The conditions were artificial, but similar to what the crew would experience in flight.
18:12Shown here is Al White, North American's chief test pilot, the man chosen to command the
18:17XB-70's maiden flight.
18:24With him is Air Force Colonel Joe Cotton, the co-pilot for much of the early test program.
18:31The backup crews shown here are Van Shepherd from North American and Lieutenant Colonel Fitzhugh
18:35Fulton.
18:44For months, these men were embroiled in the business of learning how to fly the world's
18:48most advanced and ambitious aviation project.
18:52By early September, most of the exhausting static tests had been completed.
18:57Now the most revealing tests would begin.
19:00Tests with the aircraft in motion.
19:02Then, eventually, tests of the XB-70 in flight.
19:08Before the engines were fired up, the complicated in-flight recording systems were primed to record
19:14every technical event as it occurred.
19:23This view of the Valkyrie gives a clear picture of what became known as the six-pack.
19:28When they grouped together, this phenomenally powerful combination of six jet engines were
19:33to propel the Valkyrie to speeds considered impossible only a few years before.
19:39Now hundreds of mechanical functions were checked.
19:43They would have to perform perfectly if the Valkyrie project was to succeed.
19:47The aircraft was removed from all external power sources.
19:54the Valkyrie has to record with a Valkyrie.
19:55That means that the vehicles of the Valkyrie and the Valkyrie have to operate all the
20:14areas and are defined.
20:15After a series of taxi runs, pilot and technicians were satisfied that the Valkyrie was ready
20:41for its maiden flight. On September 21, 1964, the XB-70A positioned itself at the end of the
20:49Palmdale runway for an historic moment for North American aviation and the United States Air Force.
21:04Here, as planned, white and cotton were in the cockpit.
21:08At exactly 8.38, the Valkyrie took to the air for the first time to begin a series of
21:13effort-making test flights.
21:25The Valkyrie took to the air for the first time to begin a series of missions.
21:28The Valkyrie took to the air for the first time to begin a series of missions.
21:38Accompanied by a single chase plane, simple routine checks were made as the pilots experienced the
21:56ways of the Valkyrie in flight.
22:02One of the first tasks was to retract the aircraft's advanced landing gear,
22:06but the mechanism failed to respond.
22:15With hundreds of millions of dollars of high technology in his hands,
22:32White set the landing gear back into its original position.
22:35The gear slowly responded to the cockpit control.
22:39Clearly, the first tests were to be made wheels down.
22:42Nevertheless, an alternative plan was available, and the plane continued on its maiden flight,
22:56although one engine was shut down when a warning light flashed.
22:59Over 60 minutes of valuable testing was gained by the time the aircraft headed back home to Edwards Air Force Base.
23:10On landing, one of the rear brakes locked, setting that landing gear on fire.
23:35Sitting 20 feet above the ground with the aircraft handling impeccably,
23:39the crew had to be told of the fire by the chase plane.
23:49I've heard the Jettison.
23:51Jettison.
23:53Jettison.
23:54Jettison, I have 74.
24:01Your half tires are blown, and they're both burning, but not very badly.
24:05You've got three power trucks, will you?
24:09Two weeks after its first flight, with its landing gear, engine, and brake problems all resolved,
24:19the XB-70 was ready for its second trial.
24:22On an early autumn morning, pilot Al White rotated test air vehicle number one into flight.
24:29This time, there were two chase planes, so the landing gear retraction could be viewed from both sides.
24:57A second attempt was made to lift the gear in flight.
25:05Again, anxious moments passed as the chase plane crews watched.
25:09There we go, with the gear on the count of three, two, one, gear up.
25:18Handle up.
25:25Oh, there's an opening.
25:27Three, green lights are out.
25:30Looks good.
25:30Those gear is up and door locked.
25:49We can feel well.
25:49Now, with the landing gear stowed away, the Valkyrie could begin tests at higher speeds.
26:19As the plane climbed to altitude, a warning light flashed in the cockpit, alerting the pilots to a minor failure in one of the hydraulic systems.
26:29As a precaution, White lowered the landing gear again and pointed the aircraft towards an alternative destination, Rogers Dry Lake, which provided the security of an 11-mile natural runway.
26:49하, the ship is in a northwesteighth of the other – 20
26:57That is where you wanted us to go, and then accessible to the equivalent to the reserve of the witnesses масштаб sage in the ridge of the spawns.
27:09Everything the shuttle стрela stacks of the other land should be left to the edge of theへ the building which is called modern mapping.
27:15the approach was smooth the brakes operated effectively and the Valkyrie made a perfect
27:32landing after the flight it was learned that a fractured pipe had set off the warning light
27:39but considering the enormous complexity of the aircraft this and the other problems
27:44encountered were hardly unexpected the pilots reported that the Valkyrie behaved in a predictable
27:50and comfortable manner they were coming to terms with the world's most powerful aircraft
27:55while the first prototype was being tested construction of the second xp-70 proceeded
28:01steadily the massive tubular fuselage was married to the six-pack the enormous white fins that would
28:08direct the Valkyrie were already in place lessons learned from the construction of the first
28:20prototype rapidly reduced the manufacturing time of air vehicle number two
28:24the second aircraft differed from the first in a subtle design change an extra five-degree dihedral was
28:49added to the wings to improve flight stability here one of the massive wingtips is being fitted this
28:58unique feature was until recently the largest single moving surface unit fitted to an aircraft the presence
29:06of these wingtips would enable the unique compression lift principle to propel North Americans brainchild into
29:12the trisonic stage back at Edwards air vehicle number one was rising into the sky again
29:25now white cotton and the engineers had sufficient confidence to push the Valkyrie beyond the speed of
29:43sound on no less than three occasions the plane was taken supersonic then lowered to subsonic flight
29:55but doing this stress the aircraft which was designed to be flexible as a result much of the thick white paint
30:02that covered the aircraft surface flaked and peeled away but all concerned would have agreed that it was a
30:11small price to pay to get the XP 70 past the speed of sound
30:41however for this aircraft to reach Mach 3 it would have to go much faster and testing continued
31:11October 24th saw the plane's fourth takeoff at approximately 40,000 feet the folding tips which
31:19had previously never been used were lowered to the halfway position this would improve the aircraft's
31:25stability and reduce the wing drag effect at this stage cotton applied full afterburners to the six-pack
31:31and the slender white shape of the Valkyrie began its steady increase in speed
31:36on October 14th 1965 during its 25th flight at an altitude of 70,000 feet with wingtips fully lowered air
32:05vehicle number one reached its goal three times the speed of sound
32:09but despite its technical success and its success at meeting sacks need for a heavy bomber many times
32:23faster than the b-58 hustler the Valkyrie was not destined to be adopted in military service the Air Force
32:31knowing the plane would not be accepted as a bomber had tried to acquire 150 Valkyries for a reconnaissance
32:38role but the survivability of high-flying planes over enemy airspace was now considered doubtful
32:48Soviet anti-aircraft missiles had managed to down a U-2 spy plane which could fly at heights previously
32:55considered safe from any attack missiles also competed with the high-speed bomber concept within the U.S. Air Force
33:05SAC now had intercontinental ballistic missiles to carry their nuclear bombs weapons that were more economical and
33:12unstoppable than airplanes from the early 1960s on the ICBM was considered the primary means of delivering nuclear weapons
33:22the ICBM also allowed the U.S. Navy to play a role in strategic bombing as its submarines off the
33:52effort platforms that were highly mobile and could not be detected an enormous advantage that Air Force
33:58bombers would not enjoy until the advent of the B-1B and the B-2 the XB-70 faced an uncertain future
34:06despite the Pentagon's decision not to deploy its supersonic bomber Air Force testing of the two XB-70
34:14Valkyrie prototypes continued
34:20one unique feature of the plane the crew escape capsule was a masterpiece of engineering should the Valkyrie depressurize the capsules clam like top and bottom shells would automatically roll forward and
34:33completely engulf the crew member in an airtight module from here the pilot would still have limited control over the aircraft and if necessary the entire capsule could be fired from the plane into the air
34:45these capsules were to play a very important part in the final chapter of air vehicle number two
34:51seen here with its slightly raised wings air vehicle number two takes off on a routine test mission on June 8th 1966 Al White was in command but he had a new co-pilot major Carl S Cross beside him
35:07Cross was an extremely experienced pilot who had just joined the XB-70 project
35:24at 8 27 in the morning after testing the Valkyrie joined a formation with four chase planes the event would be recorded by an accompanying Learjet
35:33the exercise was simple enough and shouldn't have presented any problems on the Valkyrie's inside right was an F-104 flown by test pilot Joe Walker Walker who was slated to join the XB-70 flight program probably had more supersonic experience than any man alive
35:51he recently completed a flight program on North American's X-15 the fastest plane on earth
36:01flying below and slightly behind the Valkyrie's right wing Walker's F-104 starfighter somehow veered too close to the Valkyrie
36:09this shot taken from the aircraft on the Valkyrie's left is reversed to give some indication of what Joe Walker may have seen moments before his starfighter collided with the XB-70's wingtip
36:27possibly the vector effect on the giant bomber pulled the little fighter into its massive wingtip
36:34in any event in a matter of seconds the F-104 was hit and rolled into an inverted position across the top half of the Valkyrie's massive frame
36:42as it did so it struck both the XB-70's vertical fins and the left wingtip before it fell thousands of feet to its destruction
36:49then with a dreadful shudder the Valkyrie rolled over and started a steep spin
36:56Al White reached for the ejection mechanism within his capsule and was fired out of the stricken aircraft seconds before it struck the desert
37:04his co-pilot was not so lucky and remained in the plane
37:09probably the G-forces of the descent stopped his ejection
37:13by 936 air vehicle number two was reduced to a smoldering carcass in the desert
37:20emergency helicopters rushed to the site but there was little chance that Major Cross could have survived
37:29however about 10 miles away the escape capsule containing Al White was spotted
37:35White was badly injured and over the next several days his life hung in the balance
37:46his capsule had not landed correctly but mercifully his pilot seat had broken when it reached the ground reducing the impact
37:53over the days that followed technicians and project officials studied the records for clues
38:05but the story was simple enough
38:08somehow the little F-104 fighter had accidentally collided with the largest plane in the world
38:13and on that fateful morning in one action America lost two brave test pilots
38:18and one of the only two Valkyries ever to be produced
38:24Al White the Valkyries first pilot and the man who flew more flights of the XB-70 than anyone else
38:31recovered from the crash but never flew the XB-70 again
38:481.7%.
38:582.1%.
39:042.3%.
39:072.1%.
39:39After air vehicle number two crashed, the remaining XP-70 continued to be tested over a period of five years. It was to log 83 test flights, and the research that it and it alone could do would provide valuable information for supersonic transport evaluation and many other projects relating to size, weight, heat, and speed.
40:09But in some ways, the Valkyrie had also been a military success. Years later, it was learned that the Soviet Union so feared the potential of the XP-70 that it had tried to develop its own smaller version.
40:29The Soviet's fear of the Valkyrie was also demonstrated in another way.
40:47For it's now known that the Russians developed, at tremendous expense, the high-performance MiG-25 Foxbat.
40:55This fighter's sole function was to protect Russia from high-flying supersonic bomber aircraft.
41:02Aircraft like the Valkyrie.
41:04The paradox was that it seems likely that Russian scientists used North American's vigilante bomber as the pattern for the Foxbat.
41:17The similarities are just so close, both in size and in shape, that it seems certain that Soviet designers used American research of the early 1950s to protect the Soviet Union from American bombers of the 1960s.
41:33Eventually, the one remaining Valkyrie was phased out of test service.
41:55Air vehicle number one landed for the last time at Wright-Patterson Air Force Base, home of the United States Air Force Museum.
42:05Piloted by Fitzhugh Fulton and Ted Stumfall, it was still collecting valuable data, even on its last flight.
42:25Shortly before it was signed over to the museum curator, complete with its logbook and a brief ceremony, one of the pilots is reported to have said,
42:37I would give anything to keep the Valkyrie in the air, except pay for it myself.
42:55The Valkyrie program had been expensive.
43:02The cost of the project, divided by the number of flights, cost American taxpayers $11 million every time it took to the air.
43:11But there can be little doubt that North American aviation engineers had not only achieved a technical wonder,
43:18they had produced one of the world's truly great planes.
43:25The Valkyrie program has been completely integrated into the air operation.
43:34The Valkyrie program has been approved in two countries to do things that southerly certain parts of our countries.
43:38The Valkyrie program has beeniciosades for leopard robots, overseas fly
43:49by the National beiassemblage, which is shaped by Lookingorac.
43:51You can respond to the LJ version of them in a차iatron SD card,
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