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After 45 years the SR-71 is STILL the fastest aircraft in the world

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Wardog

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At the height of the Cold War, Lockheed's Skunk Works designed an airplane that would prove to be the greatest photo reconnaissance aircraft ever built. The SR-71 Blackbird could fly through any airspace in the world with near impunity. It flew so high and fast that even surface-to-air missiles were largely ineffective against it. This Mach 3-plus jet was designed and built by Lockheed's genius Kelly Johnson and his staff (story, P. 24).

On December 22, 1964, Lockheed test pilot Robert J. Gilliland took the Black*bird up for its first flight. During the 56-minute test, he clocked speeds of Mach 1.5 at 46,000 feet, which at the time was unheard of for any new aircraft's initial flight. This was an indicator of the po*tential the Blackbird would realize with the U.S. Air Force.

It took close to a year to iron out all the kinks, but in January 1966 the first SR-71 entered USAF service. The first mission-capable Blackbird was delivered to Beale Air Force Base in northern California in early April of that year. These high-flying supersonic aircraft would carry out their worldwide mission for the next 25 years before being forced into retirement by budget cuts.

As the Vietnam War heated up, so did the SR-71's workload. In 1968 it began operations over North Vietnam and Laos, averaging about one sortie per week until 1970, when the schedule was bumped up to two sorties per week, then maxed out at a sortie every day in 1972. The intel gathered during these flights was invaluable, and no Blackbirds were lost to enemy action. Speed, altitude and stealth were major factors in keeping the SR-71 safe because Hanoi was ringed with the latest SAMs provided by the Soviets.

The 1970s proved to be the most noteworthy period for the high-Mach Blackbird. On September 1, 1974, Major James Sullivan and his backseater, Major Noel F. Widdifield, set a speed record in SR-71A serial no. 64-17972, flying from New York to London in 1 hour 54 minutes and 56 seconds, for an average speed of 1,806.96 mph. Less than two weeks later, the same airplane made a long-distance sprint from London to Los Angeles in record time. The pilot on that flight, 31-year-old Captain Harold B. "Buck" Adams, had at age 28 become the youngest airman to fly the SR-71. His reconnaissance systems officer was Major William C. Machorek. Their historic September 13 flight would stretch across seven time zones and take almost twice as long as the New York–to–London dash.

Captain Adams flew in the SR-71 program for four years and accumulated about 350 to 400 hours in the Black*bird. He also piloted B-52 bombers during the Vietnam War, logging 137 combat missions over Southeast Asia between the two aircraft. After he was deployed to Seymour Johnson Air Force Base in North Carolina following the October 1973 Yom Kippur War, he flew one of his most memorable SR-71 missions—a 10-hour 20-minute round trip to the Middle East requiring five aerial refuelings—for which he and his backseater were awarded the Distinguished Flying Cross.

The story of the record-breaking London–Los Angeles flight began after the September 1 New York–London run, when no. 972 was put on display at the Farnborough International Airshow. This is one of the biggest annual airshows in the world, with all the major air forces participating in some way, usually with their newest and most sophisticated aircraft.
Adams, who retired from the Air Force as a brigadier general in 1992, recalled the events that led up to the record flight: "Senator Barry Goldwater, a two-star general in the reserves, had previously flown in an SR-71, and he convinced President [Gerald R.] Ford to send the aircraft to England to put it on display to demonstrate American technology. That's when we got the go-ahead for the mission. Our wing commander picked two flight crews, and I was lucky enough to be the pilot on the return flight.

"Mission preparation for the record flight was pretty straightforward. We just sat down in the briefing and went over suit time, start time, taxi time, launch time, etc. We also covered details of the flight route itself and all the events that we could expect along that route. So we had the frequencies of the tankers that we would have to talk to, ground control, flight path so that if we lost an engine and had to abort the mission we would know where to go. This was all standard procedure on any mission you flew in the Blackbird."

After the Farnborough show came to a close, 972 was transferred to RAF Mildenhall, where the ground crews made final preparations for its flight back to the States. On the morning of September 13, the weather over Britain was perfect, and takeoff was right on time. As was routine for any Blackbird mission, the crew took off with a light load of fuel and then met up with the first tanker off the northeast tip of the country.

"Once we left Mildenhall we flew southeast, turned and came across London going northeast at the timing gate [the beginning of the official time recorded for the speed record]," recalled Adams. "The first 53 minutes of the mission were all subsonic because we flew up off the coast and refueled with three tankers, and then accelerated to altitude. We could not go supersonic over England.

"If we had taken off from Mildenhall, picked up a tanker and then moved up to altitude and hit our max speed immediately and gone across the timing gate at Mach 3-plus over London, we could have cut our flight time by 48 minutes," Adams said. "We crossed the Atlantic Ocean at Mach 3.2, which equates to about 2,200 mph. We did the Great Circle route from the UK, crossed the North American coast over Newfoundland and descended from 80,000 feet to 25,000 feet to meet up with three more tankers, one of which was a spare. We filled our tank and then began accelerating back up to our optimum altitude. We began to encounter some very strong headwinds—100 knots—in the refueling track, which chewed up some valuable time, so I started the acceleration sooner than planned to reduce the effect of the headwind."

The streaking Blackbird entered the United States just south of the Great Lakes. Adams said he and Machorek had agreed to radio Gen*eral Russell Dougherty, commander of the Strategic Air Command, as they passed over the Midwest. When they were near SAC's command post in Omaha, Neb., they gave him a call and updated him on their expected arrival time in Los Angeles.

"At that time, we had every intention of setting a world speed record," Adams explained. "As we approached California, we started to decelerate so we would be subsonic by the time we got to the mountain range on the east side of Los Angeles. We then went all the way to the coast, which was several minutes of flight to LAX because they had a radar timing gate there. We flew through it, and then we knew we had completed the mission successfully and they had confirmed the time."

The total time for the record flight was 3 hours, 47 minutes and 39 seconds. Adams and Machorek had covered nearly 5,447 miles at an average speed of 1,435.59 mph.
"We turned around and headed back over the mountains out to the desert," continued Adams, "and met up with the tanker, where we picked up 30,000 pounds of fuel. Then we flew up to Beale AFB, where we did a couple of flyovers and landed. Needless to say, the press was there, along with a sizable crowd."

Although the London–L.A. flight came off without a hitch, and Adams said any one of many pilots could have flown the mission, he also noted: "I could never say that flying the SR-71 was uneventful, especially when you're in an aircraft that can travel one mile in 1.8 seconds! Both crew members have to be constantly alert to make sure everything is performing the way it should. While we did set a speed record, I feel that all the support people who participated in making this happen should be recognized for the outstanding job they did.

"The real heroes of the SR-71 story are the Lockheed Skunk Works designers and engineers who built a phenomenal aircraft that could exceed Mach 3 and withstand 1,200 degrees F, and the maintenance crews that kept that magnificent bird in the air."
 
(Following excerpt from 'Skunk Works' by Ben Rich)

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The SR-71 is by far the most advanced and curious aircraft of the 20th century. Given the design veiw of aircraft of the time (1950's..ie F-86 and F-100) the SR-71 is light years ahead of anything around. It looks like a space ship...flies like a spaceship... Why? How did we get from barely Mach 1 to excess Mach 3+ in less than 5 years?....I would propose reverse engineering from Groom Lake ..Area 51...yes..Alien Technology.
 
The SR-71 is by far the most advanced and curious aircraft of the 20th century. Given the design veiw of aircraft of the time (1950's..ie F-86 and F-100) the SR-71 is light years ahead of anything around. It looks like a space ship...flies like a spaceship... Why? How did we get from barely Mach 1 to excess Mach 3+ in less than 5 years?....I would propose reverse engineering from Groom Lake ..Area 51...yes..Alien Technology.

Now there's an interesting theory :)
 
The SR71 is indeed an amazing aircraft. In looks as well as in performance. But it needed a lot of money to become one. And the speed difference with the ordinary jetfighters was big but not that big. The F104 Starfighter was already in service since 1958 and was a Mach 2 jet. And the F4 Phantom was in service since 1960 was even faster. The SR71 came into service in 1966.

If it was alien technology which helped to make the SR71 possible, I'm curious in which parts of the aircraft this technology was put.
 
Article: SR-71 Blackbird: the SR-71 Blackbird is a long-range, high-altitude, supersonic-cruise reconnaissance platform, and one of the most spectacular aircraft ever built.(Cover Story)

Article from:
Advanced Materials & Processes
Article date:
May 1, 2003
Author:
Merlin, Peter W. CopyrightCOPYRIGHT 1999 ASM International. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights or concerns about this content should be directed to customer service. (Hide copyright information)

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The SR-71 Blackbird is a deltawing reconnaissance aircraft designed and built by Lockheed for the U.S. Air Force nearly 40 years ago. Made almost entirely of titanium, it can fly more than 2200 mph (Mach 3.2) and at altitudes of over 85,000 feet.

Perhaps the most impressive characteristic of the SR-71 Blackbird is the fact that it was designed before the advent of supercomputing technology. A small team of talented engineers, using slide-rules and know-how, built an airplane capable of flying faster and higher than any air-breathing craft before or since. In addition, they had to invent new methods for parts fabrication, tooling assembly, construction, and testing. In the end, the Blackbirds were retired because they were expensive to maintain and operate, not because they had reached the end of their service life.

Besides the SR-71, the family of aircraft known collectively as the Lockheed "Blackbirds" includes the A-12, YF-12, and M-21. Designed by Clarence L. "Kelly" Johnson under Project OXCART, the A-12 resulted from a series of designs for a successor to the U-2 spy plane. The twelfth design in Johnson's Archangel series was a sleek aircraft built almost entirely of titanium. With powerful turbo-ramjets, the A-12 was capable of reaching a speed of Mach 3.29 and an altitude of 90,000 feet.

[ILLUSTRATION OMITTED]

In 1964, the Air Force began testing the aircraft's weapons system and worked on solving troublesome problems with transonic acceleration and various subsystems. On May 1, 1965, the aircraft set several official speed and altitude records, including a closed course speed of 2070.101 mph and a sustained altitude of 80,257.65 feet.

The year 1964 also marked the debut of two more Blackbird variants, designated M-21 and SR-71. The M-21, a two-seat variant of the A-12, was built expressly as a launch aircraft for the secret D-21 reconnaissance drone. A fatal accident during the fourth launch resulted in destruction of both drone and M-21, and the death of the launch control officer.

The second new Blackbird, the SR-71, became the most familiar member of the family. Operated by the U.S. Air Force under project SENIOR CROWN, the SR-71 served as a workhorse of aerial reconnaissance around the world for over 25 years.

The A-12 fleet operated in secret until June 1968. At that time, all of the A-12 aircraft ended their service lives and were placed in storage at Lockheed's facility in Palmdale, California. Their operational mission had been assumed by the SR-71A, operated by the Air Force.

The YF-12A program ended on February 1, 1968, and the aircraft joined the A-12s in storage. There they remained until the National Aeronautics and Space Administration (NASA) reached an agreement with the Air Force for a joint research program. Beginning in 1969, NASA operated two YF-12A aircraft and one SR-71A (temporarily designated YF-12C for political reasons). The joint NASA-Air Force program continued for ten years.

The Air Force retired the SR-71 fleet in 1990, but two airframes were reactivated for operational service in 1995. They were ultimately retired in 1998. NASA operated the SR-71 between July 1991 and October 1999 for research and to support the Air Force reactivation program. After retirement from NASA service, all remaining Blackbird airframes were allocated to museums.

Building the Blackbird

Lockheed engineers faced unique challenges in designing and building the Blackbirds. The aircraft's flight profile demanded structural materials able to withstand prolonged exposure to high temperatures from aerodynamic heating, in some places exceeding 1000[degrees]F (540[degrees]C). Therefore, fully 93% of the vehicle's structural weight consisted of titanium alloys. Since all-titanium construction had not yet become common, Lockheed engineers and technicians pioneered new inspection, test, quality-control, and manufacturing techniques.

Lockheed technicians found that the machinability of titanium had a great effect on overall cost of construction. The initial rate of metal removal from high-strength titanium alloys was only 5% of what the rate would be for aluminum. It was impossible to obtain die forgings to final dimensions or extrusions in finished form. Lockheed had to invent new drills, cutting machinery, powerheads for profilers, and cutting lubricants to increase the rate of metal removal. On some large components, which were cut on tape-controlled profilers, approximately 90% of the forging weight had to be removed by machining. To save on structural weight, many assemblies contained large numbers of small parts. In similar aluminum assemblies, many of these parts would have been combined to reduce the parts count.

Moreover, large sections of the leading and trailing edges, vertical stabilizers, chines, and inlet spikes were made of "plastic" laminates of phenyl silane, silicone-asbestos, and fiberglass. These materials--featured primarily on the A-12 and SR-71 families--helped reduce the aircraft's radar signature. However, titanium replaced the composite laminates in most areas in the A-12 prototype, TA-12 trainer, both M-21 motherships, and the three YF-12A prototypes.

High-emissivity paint

The Blackbirds earned their nickname because they were coated with a high-emissivity black paint to radiate heat. The paint used on the Blackbirds had an emissivity of 0.93, as compared to 0.38 for an unpainted titanium surface. This resulted in a surface temperature reduction between 25 and 50[degrees]F (14 and 28[degrees]C) at cruising altitudes, well worth the additional 60 pounds added to the takeoff weight.

Titanium is characteristically light, strong, heat-resistant, and nonmagnetic. Its strength is very close to that of corrosion-resistant steel, but with just slightly over half the density. Three types of titanium alloys were used in the Blackbirds.

* A-A110AT contains approximately 5% aluminum and 2.5% tin.

* B-120VCA contains approximately 13% vanadium, 11% chromium, and 3% aluminum. Most of the Blackbird's titanium skin, ranging in thickness from 0.020 to 0.040 in. (0.5 to 1.0 mm), consisted of B-120VCA sheet fastened to the frame by riveting or spot-welding.

* C-120AV contains approximately 6% aluminum and 4% vanadium.

The Blackbirds also incorporated A-126 corrosion resistant steel in some parts of the structure and surface panels. This heat-treatable alloy contains approximately 15% chromium, 26% nickel, 2% titanium, and 1% molybdenum. It was capable of withstanding 1200[degrees]F (650[degrees]C), well within the aircraft's performance envelope.

Areas subject to extremely high temperatures, such as the engine nacelle exhaust ejector section, incorporate two types of nickel alloys. Nickel-base Rene 41 is alloyed with chromium, iron, molybdenum, cobalt, titanium, and aluminum. It can withstand temperatures up to 1600[degrees]F (870[degrees]C). Hastelloy-X, an alloy of nickel with chromium, iron, and molybdenum, can withstand approximately 2200[degrees]F (1200[degrees]C).

Composite parts

Composite parts, consisting of silicone-asbestos and phenyl silane glass laminates, make up most of the peripheral assemblies on the A-12 and SR-71 series aircraft. They were used extensively in the forward fuselage chines, wing edges, inlet spike cone, tailcone, and vertical stabilizers. Composite honeycomb sandwich skin panels, some over one inch thick, were fastened to the underlying titanium framework and were easily removed for maintenance or replacement. They were applied to areas that typically experienced 400 to 750[degrees]F (200 to 400[degrees]C) during high-speed cruise.

The Blackbirds incorporated not only some cutting-edge materials, but also some novel design concepts. The Lockheed team developed a monocoque structure for the fuselage and nacelles, and a multispar/multirib wing structure with cordwise corrugations for stiffness. The fuselage side-fairings, or chines, generated almost 20% of the aircraft's total lift. Acting as fixed canards, they also produced a favorable effect on trim drag. Additionally, vortices from the chines improved directional stability of the aircraft as angle-of-attack increased. The chines also provided a convenient housing for wires and plumbing on either side of the cylindrical center-body fuel tanks.

Forward fuselage

The forward fuselage structure has a circular cross-section, and the fuselage rings are comprised of aged B-120VCA titanium alloy. Tapered chines blend into the sides, but are not integral with the fuselage structure. They are attached to it like fairings, and are partitioned into compartments to house electronics and additional mission equipment.

The fuselage is covered by titanium skin, while silicone-asbestos panels cover the chines. The chine support structure is made mostly of annealed B-120VCA titanium. Equipment bay doors are composed primarily of A-110AT material with some extruded sections as stiffeners. Fuselage longerons, located at the top, bottom, and sides, consist mostly of C-120AV aged titanium extrusions.

Canopies enclose each flight station. The A-12 was a single-seat aircraft, but all the other Blackbirds had two cockpits. The rear-seat position served a different function, depending on the aircraft model: reconnaissance (A-12, SR-71A), trainer (TA-12, SR-71B), interceptor (YF-12A), or mothership (M-21). Each canopy consists of a fabricated titanium frame which accommodates two side glass assemblies. Each glass assembly is comprised of two sealed glass panels separated by a 9/32-inch airspace.

The airspace acts as an insulating barrier against aerodynamic heating. Gaskets prevent excessive leakage of cockpit pressurization, but a small amount of air is allowed to bleed through between the panels to prevent fogging. An angular windscreen is provided only for the pilot's position, and for the instructor's cockpit on trainer models. It consists of two glass assemblies, sealed and secured in a V-shaped titanium frame. The windscreen glass assemblies are similar to the side panels, but are coated with magnesium fluoride to reduce glare.

The glass assemblies are capable of withstanding high temperatures and high impact forces. The laminated inner glass assembly consists of a 1/4-inch-thick outer tempered glass panel, a 1/8-inch-thick silicone plastic layer, and a 3/16-inch-thick inner tempered glass panel. The outer glass assembly includes a 3/8-inch-thick glass panel. At cruise, temperatures reached 420[degrees]F (215[degrees]C) on the outer surface of the glass panels and 450[degrees]F (230[degrees]C) on the adjacent titanium skin. By comparison, boundary-layer air outside the cockpit reached 632[degrees]F (333[degrees]C), while the inner surface of the cockpit was about 80[degrees]F (26[degrees]C). To keep the pilot cool, it was necessary to feed air cooled to -40[degrees]F (-40[degrees]C) into the cockpit to maintain temperatures at around 60[degrees]F (15[degrees]C).

Engine materials

The engine inlet spike assembly is a conical structure located in the center of each inlet. Moving the spike back and forth controls the amount of air entering the engine. The spike is moved forward during subsonic flight and aft during supersonic cruise. The A-12 prototype, TA-12 trainer, M-21 motherships, and YF-12A were equipped with titanium alloy spike assemblies. All other variants had spike assemblies with a titanium tip and substructure, but the external surfaces and some internal components were made of silicone-asbestos reinforced plastic materials.

Propulsion for the Blackbirds consisted of two Pratt & Whitney JTD-11B-20 (J58) afterburning turbojet engines. Each had nine compressor and two turbine stages. A variable geometry inlet diffuser and a complex bleed bypass system allowed for high engine efficiency in the Mach 2 to Mach 3.2 flight regime by controlling the location of the shockwave inside the inlet and allowing air to bypass the turbine section and flow directly to the afterburner.

The forward compressor stages and inlet case are made of titanium alloys, including Ti-8-1-1 and Ti-5-2.5, because they have good creep properties at temperatures up to 850[degrees]F (455[degrees]C). The first-stage turbine vanes incorporate Mar-M-20-ODS, a nickel-base alloy that was cast with spanwise columnar crystal grains. Its granular structure reduced the risk of thermal shock cracking. Most J58 engine components are made of Waspaloy, an oxidation-resistant nickel-base alloy capable of withstanding 1400[degrees]F (760[degrees]C). Burner components are made of Hastelloy-X. Turbine disks are made of Astroloy, a precipitation-hardened nickel-base alloy suitable for operations up to 1500[degrees]F (815[degrees]C).

Flight controls

In contrast to some of its other, more advanced concepts, the aircraft operated with fairly conventional flight controls. The inboard and outboard elevons provided pitch and roll control, and the two all-moving vertical fins provided lateral control. The vertical control surfaces had to be large enough to counteract the effect of severe yaw during an inlet unstart or engine failure. (An unstart resulted when the shock wave moved outside the engine inlet).

[GRAPHIC OMITTED]

Because of thermal soak requirements, control cables were made of Elgiloy (40Co-20Cr-15Ni-7Mo-0.1C-0.04Be), a material typically used in watch springs. Stability augmentation was controlled by a triple-redundant fail-operational electronics system. Although the Blackbird designers considered fly-by-wire and adaptive flight controls, they rejected them because of potential unknown problems that might develop in the extreme operational environment of the aircraft. NASA researchers later adopted an experimental digital control system.

Fuel system

Because it operated in an environment of high aerodynamic heating, the Blackbird required a special low-vapor-pressure (high flash point) fuel, designated JP-7. It is so difficult to ignite that a lit match thrown into a puddle of it is extinguished. Consequently, a catalytic igniter called triethylborane (TEB) was injected into the fuel for engine start and afterburner ignition. Although they included 10,000 linear feet of sealant, the tanks leaked a considerable amount of fuel while on the ground, as a result of the provisions for expansion and contraction of the tanks with changes in temperature.

According to NASA YF-12 project engineer Gene Matranga, Lockheed designers faced a difficult challenge with the sealant. They needed to find one that would be compatible with titanium, yet "remain elastic enough to move with the expanding and contracting airframe, which grows up to four inches in length when hot, shudders through an unstart, reaches temperatures over 600[degrees]F, and bounces through turbulence and taxi loads."

SR-71 Blackbird specifications

Primary function Strategic reconnaissance

Contractor Lockheed Skunkworks
Power plant Two Pratt & Whitney J58 axial-flow turbojets with
afterburners. Each produces 32,500 pounds of
thrust.
Length 107.4 feet (32.73 m)
Height 18.5 feet (5.63 m)
Weight 140,000 pounds (52,250 kg) gross takeoff weight
80,000 pounds (30,000 kg) JP-7 fuel weight
Wingspan 55.6 feet (16.94 m)
Design cruise speed Mach 3.2 / 2,000 mph (3200 kph)
RangeOver 2000 miles (3200 km) unrefueled
Altitude Over 85,000 feet (26,000 m)
Crew Two

For more information: Peter Merlin, AS & M, Inc., NASA Dryden Flight Research Center, Edwards, California; e-mail: peter_merlin@dfrc.nasa.gov.

Mr. Merlin has written a monograph about the YF-12 family of aircraft: Mach 3+: NASA/USAF Flight Research, 1969-1979 (NASA SP-2001-4525). Please contact him directly if you would like a copy.

Peter W. Merlin

Analytical Services & Materials Inc.

NASA Dryden Flight Research Center

Edwards, California
 
The SR71 is indeed an amazing aircraft. In looks as well as in performance. But it needed a lot of money to become one. And the speeddifference with the ordinary jetfighters was big but not that big. The F104 Starfighter was already in service since 1958 and was a Mach 2 jet. And the F4 Phantom was in service since 1960 was even faster. The SR71 came into service in 1966.

If it was alien technology which helped to make the SR71 possible, I'm curious in which parts of the aircraft this technolgy was put.

The difference between flying at Mach 2 in an F-104 and Mach 3.3+ in an SR-71 is like taking a drive in a Honda at 90 mph to a F1 car at 180 MPH. The aerodynamic force increase between the two speeds is squared, double the speed and the forces quadruple. The F-104 couldn't have flown any faster even if it had larger engines not due so much to limitations of it's air form shape but for limitations on the skin temperature. The aircraft aluminum alloy skin would have weakened sufficiently enough by the friction temperature to have lost most of it's strength. Although the leading edges of the wings and tail surfaces used a nickel alloy to resist the high temperatures the rest of the aircraft used aluminum (or aluminium, if you are British). The SR-71 and A-12 skin temperature could reach 1000 F or more and special cooling was required to hold it down even with the titanium skin. So, it boils down to technology. Sure the F-104 was a fast aircraft for about 20-30 minutes of flight, but when compared to the SR-71's speed, altitude and range, nothing has ever come close yet.
 
The SR71 is indeed an amazing aircraft. In looks as well as in performance. But it needed a lot of money to become one. And the speed difference with the ordinary jetfighters was big but not that big. The F104 Starfighter was already in service since 1958 and was a Mach 2 jet. And the F4 Phantom was in service since 1960 was even faster. The SR71 came into service in 1966.

If it was alien technology which helped to make the SR71 possible, I'm curious in which parts of the aircraft this technology was put.

Thing that gives advantage to SR-71 is ramjet engine. It has Pratt & Whitney J58 engine which is combination of turbojet and ramjet engine. First one for use at low speeds, second for high speeds. That spike in front of the engine is the key element of directing air flow through the engine.
Ramjet is, essentially, very simple thing (works without moving compressor, unlike regular jet engines). It takes compressed air, burn it and produces thrust. Problem is that it can not work with zero or low speeds, it needs very high speeds of air flow, around Mach 3. So, that's where 'normal' engine jumps in. It speeds up aircraft to that speed (with afterburner constantly on), and than ramjet component kicks in.
 
btw, future must be in X-43A ...
On second test flight it got Mach 9.8. It is still test vehicle...
 
The difference between flying at Mach 2 in an F-104 and Mach 3.3+ in an SR-71 is like taking a drive in a Honda at 90 mph to a F1 car at 180 MPH. The aerodynamic force increase between the two speeds is squared, double the speed and the forces quadruple. The F-104 couldn't have flown any faster even if it had larger engines not due so much to limitations of it's air form shape but for limitations on the skin temperature. The aircraft aluminum alloy skin would have weakened sufficiently enough by the friction temperature to have lost most of it's strength. Although the leading edges of the wings and tail surfaces used a nickel alloy to resist the high temperatures the rest of the aircraft used aluminum (or aluminium, if you are British). The SR-71 and A-12 skin temperature could reach 1000 F or more and special cooling was required to hold it down even with the titanium skin. So, it boils down to technology. Sure the F-104 was a fast aircraft for about 20-30 minutes of flight, but when compared to the SR-71's speed, altitude and range, nothing has ever come close yet.

But no alien technology.
 
Great pic. POS. Thanks to everybody for their knowledgeable input. This is what makes FGM what it is, participation and contribution.
 
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