Question: How many passenger service flights did the only other counterpart of the supersonic aircraft Concorde complete?

full_context: Document 1: Lockheed SR-71 Blackbird: The Lockheed SR-71 "Blackbird" is a long-range, Mach 3+ strategic reconnaissance aircraft that was operated by the United States Air Force. It was developed as a black project from the Lockheed A-12 reconnaissance aircraft in the 1960s by Lockheed and its Skunk Works division. American aerospace engineer Clarence "Kelly" Johnson was responsible for many of the design's innovative concepts. During aerial reconnaissance missions, the SR-71 operated at high speeds and altitudes to allow it to outrace threats. If a surface-to-air missile launch was detected, the standard evasive action was simply to accelerate and outfly the missile. The SR-71 was designed with a reduced radar cross-section.
Document 2: Droop-nose: The droop-nose configuration is a distinctive feature of some supersonic aircraft, most notably both Concorde and the Tupolev Tu-144. When these aircraft were in service, the pilot would lower the nose cone to improve visibility of the runway and taxiways. When in flight, the nose would be raised. Concorde also had a moving visor that would slide into and out of the nose. The Tu-144's visor was part of the nose and did not retract.
Document 3: Supersonic transport: A supersonic transport (SST) is a civilian supersonic aircraft designed to transport passengers at speeds greater than the speed of sound. To date, the only SSTs to see regular service have been Concorde and the Tupolev Tu-144. The last passenger flight of the Tu-144 was in June 1978 and it was last flown in 1999 by NASA. Concorde's last commercial flight was in October 2003, with a November 26, 2003 ferry flight being its last airborne operation. Following the permanent cessation of flying by Concorde, there are no remaining SSTs in commercial service. Several companies have each proposed a supersonic business jet, which may bring supersonic transport back again.
Document 4: Lockheed F-104 Starfighter: The Lockheed F-104 Starfighter is a single-engine, supersonic interceptor aircraft which later became widely used as an attack aircraft. It was originally developed by Lockheed for the United States Air Force (USAF), but became widely used by US Allies around the world, and produced by several other NATO nations. One of the Century Series of fighter aircraft, it was operated by the air forces of more than a dozen nations from 1958 to 2004. Its design team was led by Kelly Johnson, who contributed to the development of the Lockheed P-38 Lightning, Lockheed U-2, Lockheed SR-71 Blackbird and other Lockheed aircraft.
Document 5: Supersonic aircraft: A supersonic aircraft is an aircraft able to fly faster than the speed of sound (Mach number 1). Supersonic aircraft were developed in the second half of the twentieth century and have been used almost entirely for research and military purposes. Only two, Concorde and the Tupolev Tu-144, ever entered service for civil use as airliners. Fighter jets are the most common example of supersonic aircraft.
Document 6: Concorde: Aérospatiale/BAC Concorde ( ) is a British-French turbojet-powered supersonic passenger jet airliner that was operated until 2003. It had a maximum speed over twice the speed of sound at Mach 2.04 (1354 mph at cruise altitude), with seating for 92 to 128 passengers. First flown in 1969, Concorde entered service in 1976 and continued flying for the next 27 years. It is one of only two supersonic transports to have been operated commercially; the other is the Soviet-built Tupolev Tu-144, which was operated for a much shorter period.
Document 7: Hawker Hunter: The Hawker Hunter is a transonic British jet-powered fighter aircraft that was developed by Hawker Aircraft for the Royal Air Force (RAF) during the late 1940s and early 1950s. It was designed to take advantage of the newly developed Rolls-Royce Avon turbojet engine and the swept wing, and was the first jet-powered aircraft produced by Hawker to be procured by the RAF. On 7 September 1953, the modified first prototype broke the world air speed record for aircraft, achieving a speed of 727.63 mph .
Document 8: Supercruise: Supercruise is sustained supersonic flight of a supersonic aircraft with a useful cargo, passenger, or weapons load performed efficiently, which typically precludes the use of highly inefficient afterburners (reheat). Many well known supersonic military aircraft are not capable of supercruise as they are only able to maintain supersonic flight in short bursts (typically with afterburners) while they cruise at subsonic speeds. Aircraft such as the SR-71 Blackbird are designed to cruise at supersonic speed with afterburners enabled.
Document 9: Avion de Transport Supersonique Futur: The Avion de Transport Supersonique Futur (ATSF) also known as "Alliance" was a concept design for supersonic aircraft considered by British Aerospace and Aérospatiale. The plane was to be based on the experience learned from the supersonic Concorde, and was to fly at Mach 2 or higher. Preliminary designs were produced, with some wind-tunnel testing of small-scale models, but development apparently stalled in the early 2000s.
Document 10: Quiet Supersonic Technology: The Quiet Supersonic Technology, also known as QueSST is a project in development by NASA and Lockheed Martin that is aimed to be a quieter replacement for the Concorde. After design review, the next stage is to test models in a wind tunnel. The ground noise is expected to be around 60 dB(A), about 1000 times quieter than current supersonic aircraft. This is achieved by using a long, narrow airframe and canards to keep the shock waves from coalescing.
Document 11: Alexei Tupolev: Alexei Andreyevich Tupolev (Russian: Алексе́й Андре́евич Ту́полев ; May 20, 1925 – May 12, 2001) was a Soviet aircraft designer who led the development of the first supersonic passenger jet, the Tupolev Tu-144. He also helped design the Buran space shuttle and the long-range heavy bomber Tu-2000, both of which were suspended for lack of funding.
Document 12: Tupolev Tu-104: The Tupolev Tu-104 (NATO reporting name: Camel) was a twin-engined medium-range narrow-body turbojet-powered Soviet airliner and the world's first successful jet airliner. Although it was the sixth jet airliner to fly (following, in order, the British Vickers Type 618 Nene-Viking, de Havilland Comet, Canadian Avro Canada C102 Jetliner, US Boeing 367-80 and French Sud Caravelle), the Tu-104 was the second to enter regular service (with Aeroflot) and the first to provide a sustained and successful service (the Comet which had entered service in 1952, was withdrawn from 1954-1958 following a series of crashes due to structural failure). The Tu-104 was the sole jetliner operating in the world between 1956 and 1958.
Document 13: Mitsubishi F-1: The Mitsubishi F-1 is Japan's first post-World War II domestically developed and built supersonic military jet, to enter production in Japan since the end of World War II, thus it was nicknamed "Supersonic Rei-Sen". Mitsubishi Heavy Industries and Fuji Heavy Industries jointly developed the F-1. At first glance, it resembles the French/Anglo SEPECAT Jaguar, but was a completely independent Japanese effort (although it uses the same engines). Its primary role is anti-ship attack, secondary role is ground attack, and it has limited air-to-air capabilities (short-range AIM-9 Sidewinder for self-defense).
Document 14: Republic F-105 Thunderchief: The Republic F-105 Thunderchief was a supersonic fighter-bomber used by the United States Air Force. The Mach 2 capable F-105 conducted the majority of strike bombing missions during the early years of the Vietnam War; it was the only U.S. aircraft to have been removed from combat due to high loss rates. Originally designed as a single-seat, nuclear-attack aircraft, a two-seat Wild Weasel version was later developed for the specialized Suppression of Enemy Air Defenses (SEAD) role against surface-to-air missile sites. The F-105 was commonly known as the "Thud" by its crews.
Document 15: Tupolev Tu-144: The Tupolev Tu-144 (Russian: Tyполев Ту-144 ; NATO reporting name: Charger) is a retired jet airliner and commercial supersonic transport aircraft (SST). It is one of only two SSTs to enter commercial service, the other being the Anglo-French Concorde. The design was a product of the Tupolev design bureau, headed by Alexei Tupolev, of the Soviet Union and manufactured by the Voronezh Aircraft Production Association in Voronezh, Russia. It conducted 55 passenger service flights, at an average service altitude of 16,000 m and cruised at a speed of around 2,000 km/h (Mach 1.6).
ground_truth: 55