Supersonic Transport

1. Tupolev Tu-104:

While these major US, European, and former-USSR powers all designed supersonic transports, that surrounding the latter was the first to fly. But its development was complicated and yes it ultimately resulted in failure.

Seeking to improve speeds and minimize travel times on scheduled routes, which were flown by Aeroflot, the united states stepped approximately pure-jet technology featuring its first such airliner, the Tupolev Tu-104, if this first flew in prototype form on June 17, 1955.

The low-wing monoplane, incorporating the majority of the elements from the military Tu-16 twin turbojet bomber to relieve development time, featured a glazed nose navigator’s station, a 35-degree swept wing mounted with significant anhedral, dual wing root buried, 14,881 thrust-pound Mikulin RD-3 or AM-3 eight-stage, axial-flow turbojets, and quad-wheel main undercarriage units that retracted into wing underside fairings. Although initial capacity was 50, 70-passenger Tu-104As and 100-passenger Tu-104Bs, in five-abreast configurations, followed.

Inaugurated into service on September 15, 1956 within the Moscow-Umsk-Irkutsk route, it severely reduced flying times on the piston types it replaced.

“At some time of its entry into service, the Tu-104 was really the only turbojet-powered transport in airline service,” based on John Stroud in “Soviet Transport Aircraft since 1945” (Putnam and Company, Ltd., 1968, p. 199), “the de Havilland Comet 1 and 1A types being withdrawn from service in 1954. It was not before the autumn of 1958 that BOAC introduced Comet 4s and Pan American World Airways Boeing 707-120s.”

Like the countries from the West, hmo’s Soviet Union thought a supersonic transport was the following logical growth and development of commercial aviation.

2. Myasishchev M-52:

The foundation for any Russian supersonic transport was laid from the Myasishchev Design Bureau’s M-52 intercontinental bomber. Powered by four Solovy’ev turbojets, a couple of which were pylon-mounted towards the high, swept wings and 2 of which were attached with their tips, it turned out intended for at the very least Mach 2 cruise speeds.

Although the only real example ever built publicly appeared in Tuscino in 1961, or even a year following the design bureau that had given birth to it turned out abolished, commercial feasibility studies of computer had been commenced. While its high-wing configuration was considered inappropriate for passenger-carrying services and its particular range was insufficient for such operations, this logic, a minimum of in the Soviet Union, was sounder than may to start with be considered, since both turboprop Tupolev Tu-114 and pure-jet Tu-104 was civilian versions of, respectively, the Tu-95 and Tu-16 bombers.

3. Tupolev Tu-144:

An all-new supersonic design was clearly needed. Because Myasishchev’s proposal was inappropriate and Ilyushin was preoccupied with rectifying the problems having its Il-62 long-range, pure-jet passenger aircraft, Tupolev, the continent’s long established military and commercial manufacturer, was selected to provide it.

The result, the Tu-144, was one from the few aircraft nearly this time initially and exclusively made for commercial operations.

Powered by four 38,500 thrust-pound engines, the aircraft featured a 188.5-foot overall length, an 83.10-foot span of their delta wing, along with a 330,000-pound gross weight. Although still only in prototype form and resembling, as you expected, Concorde in configuration, there was several differences between your two.

The fuselage, most notably, incorporated 18 percent of titanium rolling around in its construction to cater on the expected expansion and contraction cycles that resulted in the frictional heat buildup and internal pressurization, and it also was wider, that has a flatter cabin floor, for five-abreast coach seating. Its single-droop nose, deflecting towards the 12-degree position, sported top windows.

In planform, its double-delta wing featured an ogival or s-shaped innovative and trailing edge elevons, but was lacking camber or twist that has a flat bottom.

Its NK-144 turbojets, grouped in barely separated pairs, were air entered through its six-foot rectangular inlets around the leading edge and stretched across over 17 feet to its exhaust pipes on the trailing edge.

Undercarriage was comprised of a two-wheeled, aft-retracting nose unit and a couple 12-wheeled, forward-retracting main units mounted outboard on the engine ducts and rotating 180 degrees before settling within their airfoil bays.

First flying from Moscow’s Zhukovsky Airfield after executing a 25-second acceleration roll-which marked earth’s first commercial supersonic flight of a typical design-the prototype, number 68001, remained airborne for 28 minutes, which consists of landing gear extended the whole time. Unpressurized, it internally carried flight test equipment.

Although no photographs were released at any time, it is thought that a second airframe, numbered 68002, was damaged during a unique flights as well as a third, 68003, was adopted for static testing.

Fuel thirsty and range deficient, the sort, requiring consistent, 100-passenger load factors to even meet breakeven costs, indicated the requirement for an extensive redesign of any production version, which more closely reflected Concorde.

Stretched, the fuselage, now having a 215.5-foot length and sporting 34 as opposed for the previous 25 windows, facilitated accommodation of as much as 140, and its particular droop nose, of greater length, introduced side windows.

Two canards, installed around the upper fuselage immediately behind the cockpit, extended out- and toward improve the aircraft’s low-speed handling characteristics.

The compound swept, full delta wing, 94.5 feet in span, offered variable camber and sculpting as well as a circular underside.

The engines, with square inlets, were repositioned further outboard where there was greater separation between their pairs, even though the main undercarriage units, of shorter length, retracted into them.

Range, which has a 33,000-pound payload, was projected as 2,000 miles.

Numbered 77101, the 1st prototype in this extensively redesigned version first flew in August of 1972, whilst the second, 77102, was the primary exhibited from the West in the 1973 Paris Air Show. Its pride was short-lived, however.

During a demonstration flight on June 3, the aircraft produced low pass having its canard surfaces and undercarriage extended, before executing a steep, afterburner-augmented climb. Appearing undertake a stall at 3,000 feet, however, it commenced a dive, abruptly leveling off just one or two feet across the ground, at which the right wing tore off on the root.

Spitting flames by reviewing the engines, it rolled as well as the other wing dislodged itself on the structure. Exploding and plummeting to your earth, it impacted, killing the six crew members fully briefed, eight within the ground, and damaging over a hundred buildings in Goussainville, France.

Although no official cause was ever found, it was belief that the Tu-144 attemptedto land within the wrong runway, beginning a go-around once the error was discovered, which placed it on the collision course using a Mirage fighter. Diving to prevent it, it absolutely was subjected to g-forces at night airframe’s capacity and not enough altitude remained in order to recover. Its structural failure was therefore not due to any design flaw or deficiency.

After operating cargo and mail root proving flights between December of 1975 and 1976, the Tupolev Tu-144 entered scheduled service within the 2,400-mile segment between Moscow and Alma-Ata, Kazakhstan, on November 1 from the following year, operating 102 such services by having an average of 70 passengers, before these were discontinued on June 6, 1978. The aircraft logged 181 airborne hours, which often 102 were at subsonic speeds.

Despite its extensive redesign, it had neglected to rectify its deficiencies. Still excessively fuel thirsty, it had been only capable to cover the 2 main,400-mile route with half its payload capability, attained by deliberately leaving half its eats unoccupied, plus the cabin noise level, caused because of the engines along with the air conditioning needed to counteract the external, skin friction created heat, was intolerable.

The succeeding Tu-144D, fitted with uprated, less expensive Koliesov RD-36-51A turbines, and supplies hope in the event it first flew on May 23, 1978, fared little better. A fire from the left engines, propagating for the fuselage, left insufficient chance to reach another airport, inducing the aircraft to careen to a field and explode. Of the five crew members aboard, two were killed and three were injured.

Although what kind began route proving flights around the 3,480-mile sector from Moscow to Khabarovsk on June 23 on the following year plus it covered the gap in three hours, 21 minutes, it never proceeded to scheduled status. The noise, fuel consumption, and range parameters of supersonic flight can’t be transcended for commercial operations, leaving the main one prototype, both the pre-production, the nine production Tu-144s, plus the five production Tu-144Ds as the sole testaments to the present fact.

4. Tupolev Tu-144LL:

The National Aeronautics and Space Administration (NASA) teamed with US and Russian aerospace industries spanning a five-year period to conduct a joint international research program to cultivate suitable technology with an early-21st century supersonic transport that could resolve the obstacles plagued by the 3 Boeing 2707, Aerospatiale-British Aerospace Concorde, and Tupolev Tu-144 actual and still-borne designs.

Conducted included in NASA’s High Speed Research (HSR) program and managed through the NASA Langley Research Center, the project was initiated following your June 1994 agreement was signed by US Vice President Al Gore, Jr. and Russian Prime Minister Viktor Chemomyrdin.

Cornerstone of it had been the last Tu-144D, constructed almost 30 years ago and sporting tail number 77114, which itself never entered commercial service, but logged 82 hours, 40 minutes during research and test flights. Originally powered by four Koliesov RD-36-51 turbojets, which provisioned it for just a maximum Mach 2.15/1,450-mph speed at the 59,000-foot service ceiling, it stood a range of below 2,500 miles.

Modified for your joint program to Tu-144LL Flying Laboratory standard, it absolutely was retrofitted with four 55,000 thrust-pound Kuznetsov, afterburner-equipped NK-321 turbofans originally produced to the Tupolev Tu-160 Blackjack bomber, causing a Mach 2.3 speed and 3,500 nautical mile range with 224,000 pounds of fuel in a 410,000-pound maximum lift off weight.

Other modifications included digging in thermocouples, pressure sensors, microphones, and skin friction gauges to appraise the aerodynamic boundary layer, a serious event crew escape system, along with a Damian digital data collection system that replaced the previous analog one.

The first from the two-phase program, running from June of 1996 to February of 1998, entailed two ground engine and six flight experiments, which required 19 airborne sorties to finish, in the Zhukovsky Air Development Center near Moscow, and involved studies with regards to the aircraft exterior surface, the inner structure and powerplant, temperatures, boundary airflows, interior and exterior noise, airfoil ground effect characteristics, and varying flight profile handling characteristics.

The second phase, going down between September of 1998 and April of 1999, entailed six fights, which besides facilitated greater understanding with the original six airborne experiments, but provided analysis of fuselage and wind deflections, angles-of-attack, sideslip angles, and nose boom pressures.

The Boeing 2707 Supersonic Transport

he 2707, Boeing’s contender for any supersonic transport, may seem like ancient history now, nonetheless it was advanced then both in concept and technology. Perhaps that it was too much so.

Because the jet race had been recently won because of the UK together with the de Havilland DH.106 Comet along with the then-designated USSR with all the Tupolev Tu-104, the US stayed without choice when it wished to turn the tides from the supersonic sector, especially considering that the same two countries were preparing to launch such designs of their very own, respectively from the form in the Aerospatiale-British Aerospace Concorde as well as the Tupolev Tu-144 inside early 1960s.

Consensus in this particular early pure-jet period was that supersonic flights would be the next logical evolution with the subsonic one.

Submissions to fill this segment were created by several aircraft manufacturers from the United States. Boeing, by way of example, considered a Mach 1.8 aircraft, accommodating 227 passengers. Lockheed’s concept was more ambitious and radical. It produced a design proposal incorporating an airfoil-shaped fuselage and also a doubly compounded delta wing projected to realize Mach 3 speeds. Capacity, however, had not been unlike that surrounding Boeing’s aircraft at 218. Designated NAC-60, North American’s concept closely resembled the military B-70 Valkyrie, itself a supersonic design with canards, a compoundly-swept delta wing, and four aft-mounted engines grouped in pairs. It was also slated to the Mach 3 speed realm.

Boeing’s 2707-100, numerically considered the first on the second supersonic generation of airliners after its 707, was ultimately selected on December 31, 1966. Unlike the UK and USSR aircraft, that it was intended, through the outset, to eclipse the boundaries of traditional configuration, structure, and speed, offering a long service life.

Featuring titanium construction to resist the 500-degree Fahrenheit structural temperatures generated through the friction of their intended, 1,800-mph/Mach 3 cruise speed, it sported an adjustable geometry delta wing, which pivoted on screw jacks and titanium bearings to appeal to the extreme velocity variations, between low subsonic approach speeds inside the extended position to high supersonic cruise ones within the retracted one. Trailing edge flaps were fitted for that former component of flight.

The tailplane, with separate vertical and horizontal surfaces, was otherwise conventional.

Power would have been to have been supplied by four General Electric, wing-underside attached engines.

A full-scale wooden mockup with the supersonic airliner, meant to carry 300 passengers, was built.

Although the 113 optioned orders placed by 26 worldwide airlines seemed promising in June of 1967, the ambitious design had exceeded the technological expertise to change it into reality. Aside on the inherent instability it demonstrated during wind tunnel tests, the weight with the swing-wing aircraft was prohibitively excessive, carrying a 40,000-pound penalty, thus leaving less available with the fuel had to provide the range that carriers sought.

The immediate passenger capacity/payload reduction and/or fuel/gross weight increase solutions proved inadequate.

Supersonic flight, other than within the limited, high-altitude military form, was little understood right at that moment, for routine, scheduled commercial operations, and obstacles existed far beyond your chance board in the design teams. Public reactions, sometimes bordering on hysteria, as an example, included protests in regards to the sonic boom, its resultant property damage on the surface, the exclusion of overland flights (which reduced the opportunity airline market on the aircraft), the rise in world temperatures, the melting from the polar caps, the destruction of land- and ocean-dependent nature, along with the reduction in radiation protection through the ozone layer.

Bureaucratically, this software was continually delayed by airframe and powerplant reassessments and also the granting on the necessary governmental funding on the design.

Because the kind, as envisioned n its initial version, didn’t offer acceptable payload and range capabilities, a 2nd, the 2707-200, was proposed. Although it featured an elongated fuselage and Tu-144-resembling canards above and behind the cockpit, it weighed in at 750,000 pounds, that has been 25 percent over envisioned and greater than those of a 500-passenger 747-100, and therefore did not meet the FAA’s finalized design submission deadline.

Even its 23,000-pound fat reduction program placed its gross weight 52,000 pounds higher than the target.

While its radical, swing-wing feature was technologically feasible, it did not offer the needed parameters, because Boeing was struggling to integrate the pivots, engines, and undercarriage within an efficient engineering package.

Forced to abandon this variable-geometry airfoil concept, it produced another version, the 2707-300. Featuring a 268.8-foot overall length, it incorporated the fixed, supersonic standard delta wing planform employed by Concorde and also the Tu-144, using a 141.8-foot span with an 8,497-square-foot area. The horizontal and vertical tailplane, using a 50.1-foot height, remained conventional.

Powered by four 60,000 thrust-pound General Electric GE4/J5P turbojets, it offered double capacity and one-third more speed than its UK and USSR competitors, however, and was designed to transport 234 passengers 5,000 miles at 1,890-mph speeds at 60,000-foot service ceilings. The prototype’s 640,000-pound gross weight was anticipated to increase to 710,000 pounds on production aircraft.

Simplicity, coupled having a size reduction and also the elimination from the variable geometry airfoil’s weight and aerodynamic obstacles, generated lower production and unit costs, which, subsequently, Boeing believed might have attracted greater sales. That figure was then envisioned to as high as 500.

In October of 1968, or five months before Concorde first flew, the definitive 2707-300 was chosen because US’s supersonic transport design and construction of the prototype commenced in September on the following year, provisioning it as being the third airliner in their class to go in the market. But it never would.

Continually exposed to a design and development program that’s, on occasion, more turbulent than Concorde’s, it fought for survival.

The obstacles, as befitting of early 1960s commercial supersonic technology, were numerous and insurmountable, including escalating research and production costs, increasing gross weights, decreasing ranges and payloads, rising seat-mile costs, excessive fuel burns and engine noise, the need for over subsonic fares, plus the fear that high quality passengers would plunge to the higher-speed transport, leaving the common, subsonic ones without worrying about yield where they depended for profitability.

Limited along the way application, what kind could basically economically viable with good load factors on extended range routes.

Innovative technology, it had become increasingly apparent, couldn’t support the supersonic concept over a commercial level. Yet, blinded at times because of the need to recapture the title lost in the subsonic race understanding that “pride-goeth-before-a-fall” dynamic necessitated because of the desire to regain national prestige, this program remained aloft while using continued, albeit obstacle-ridden, granting of federal funds.

Part with this buoyancy, of course, was airline interest from the product, but, as occurred with Concorde, this started to wane, from when they were already financially strapped with orders for widebody 747s.

Public, government, and aircraft manufacturer doubts in regards to the 2707-300’s capacity to ever economically achieve its fore-claimed noise, payload, and range design goals caused declining confidence to coincide with diminishing enthusiasm for your concept.

Presidential support for just a supersonic transport program fluctuated widely. Escalating development costs spawned by increasing technological hurdlers and requiring additional governmental funding only generated increasing opposition going without running shoes. Because Tupolev seemed struggling to solve its Tu-144 problems and Concorde’s fuel-burn generated initial sales of only ten aircraft to Air France and British Airways (lots too small to pose any competitive threat), continued 2707-300 funding could not justified.

On March 18, 1971, therefore, the House voted against it, echoed a couple of days later from the Senate. Although supporters attemptedto restart this system by rechanneling the $85.3 million due to its termination into further development, and although House itself voted in favor with this action on May 12, the Senate rejected it five days later.

Fifteen percent with the first 2707-300 airframe ended up being cut at the time plus a 296-foot stretched version, to allow for 321 passengers, was then envisioned.

All three US, UK, and USSR programs ended up plagued by unprecedented opposition to new technology that lots of believed would are actually detrimental on the atmosphere, earth’s environment, and humanity. Because of the company’s tremendous technological leap, exploding development costs, and irresolvable engineering difficulties, it never had become the hoped-for reality within the US and, soon after route proving flights, the Tupolev Tu-144 itself was withdrawn from service from the USSR.