Question: At which airport does the low-cost airline, a subsidiary of KLM founded by John Nicolaas Block, have its main base?

full_context: Document 1: Martinair: Martinair, legally "Martinair Holland N.V.", is a Dutch cargo airline headquartered and based at Amsterdam Airport Schiphol and a subsidiary of Air France-KLM. The airline was founded in 1958 by Martin Schröder. Since 2011, Martinair has operated entirely as a cargo airline with scheduled services to 20 destinations worldwide and additional charter flights. Prior to that date, passenger flights were also operated.
Document 2: John Nicolaas Block: Johan Nicolaas Block (May 18, 1929, Amsterdam – April 11, 1994) was a Dutch aviation pioneer. He was the co-founder of Martinair, founder of Transavia and Air Holland.
Document 3: Comair (South Africa): Comair Limited is an airline based in South Africa that operates scheduled services on domestic routes as a British Airways franchisee (and an affiliate member of the Oneworld airline alliance). It also operates as a low-cost carrier under its own kulula.com brand. Its main base is OR Tambo International Airport, Johannesburg, and has focus cities at Cape Town International Airport and King Shaka International Airport. Its headquarters are near OR Tambo in the Bonaero Park area of Kempton Park, Ekurhuleni, Gauteng.
Document 4: Maarten de Jonge: Maarten de Jonge (born 9 March 1985) is a Dutch cyclist who rides for the UCI Continental Monkey Town Continental Team . He claims to have attempted to fly on both Malaysia Airlines Flight 370 and Malaysia Airlines Flight 17, but changed flights in order to save money, although no independent sources can confirm this.
Document 5: Turkish Airlines: Turkish Airlines (Turkish: "Türk Hava Yolları") () is the national flag carrier airline of Turkey, headquartered at the Turkish Airlines General Management Building on the grounds of Atatürk Airport in Yeşilköy, Bakırköy, Istanbul. s of 2017 , it operates scheduled services to 302 destinations in Europe, Asia, Africa, and the Americas, making it the fourth-largest carrier in the world by number of destinations. It serves more destinations non-stop from a single airport than any other airline in Europe. Turkish Airlines flies to 120 countries, more than any other airline. With an operational fleet of fourteen cargo aircraft, the airline's cargo division serves 64 destinations. Istanbul Atatürk Airport is its main base, and there are secondary hubs at Esenboğa International Airport, Sabiha Gökçen International Airport, and Adnan Menderes Airport. Turkish Airlines has been a member of the Star Alliance network since 1 April 2008.
Document 6: KLM: KLM Royal Dutch Airlines, legally "Koninklijke Luchtvaart Maatschappij N.V.", is the flag carrier airline of the Netherlands. KLM is headquartered in Amstelveen, with its hub at nearby Amsterdam Airport Schiphol. It is part of the Air France–KLM group, and is a member of the SkyTeam airline alliance. KLM was founded in 1919; it is the oldest airline in the world still operating under its original name and had 32,505 employees as of 2013 . KLM operates scheduled passenger and cargo services to 145 destinations.
Document 7: Cygnific B.V.: Cygnific B.V., a pan-European service provider is a subsidiary of KLM Royal Dutch Airlines that was founded in 1998. Cygnific is based in Amsterdam but also has a service centre in Enschede. About 700 employees assist customers and travel agents in a variety of countries and languages. By carrying out reservations, providing general information and supporting the KLM website Cygnific handles every year approximately 3 million transactions.
Document 8: Jacob Veldhuyzen van Zanten: Jacob Louis Veldhuyzen van Zanten (5 February 1927 – 27 March 1977) was a Dutch aircraft captain and flight instructor. He was the captain of the KLM Royal Dutch Airlines Boeing 747 which was involved in the Tenerife airport disaster, the deadliest accident in aviation history.
Document 9: Transavia: Transavia, legally incorporated as "Transavia Airlines C.V." and formerly branded as "transavia.com", is a Dutch low-cost airline and a wholly owned subsidiary of KLM and therefore part of the Air France-KLM group. Its main base is Amsterdam Airport Schiphol and has further bases at Rotterdam The Hague Airport, Munich Airport and Eindhoven Airport. Transavia maintains Transavia France as its French subsidiary.
Document 10: Anthony Fokker: Anton Herman Gerard "Anthony" Fokker (6 April 1890 – 23 December 1939) was a Dutch aviation pioneer and an aircraft manufacturer. He is most famous for the fighter aircraft he produced in Germany during the First World War such as the Eindecker monoplanes, the Dr.1 triplane and the D.VII biplane.
Document 11: Air France: Air France (] ; formally "Société Air France, S.A."), stylized as AIRFRANCE, is the French flag carrier headquartered in Tremblay-en-France. It is a subsidiary of the Air France–KLM Group and a founding member of the SkyTeam global airline alliance. As of 2013 Air France serves 36 destinations in France and operates worldwide scheduled passenger and cargo services to 168 destinations in 93 countries (including overseas departments and territories of France) and also carried 46,803,000 passengers in 2015. The airline's global hub is at Charles de Gaulle Airport with Orly Airport. Air France's corporate headquarters, previously in Montparnasse, Paris, are located on the grounds of Charles de Gaulle Airport, north of Paris.
Document 12: KNILM: Koninklijke Nederlandsch-Indische Luchtvaart Maatschappij (in English: Royal Dutch Indies Airways) was the airline of the former Dutch East Indies. Headquartered in Amsterdam, KNILM was "not" a subsidiary of the better-known KLM (Royal Dutch Airlines), despite the similar name. The airline had its headquarters in Amsterdam and an office in Batavia (current Jakarta).
Document 13: Tony Jannus Award: The Tony Jannus Award recognizes outstanding individual achievement in scheduled commercial aviation by airline executives, inventors and manufacturers, and government leaders. The award is conferred annually by the Tony Jannus Distinguished Aviation Society and was first bestowed in 1964 in Tampa, Florida, U.S. Its namesake, aviation pioneer Tony Jannus (1889–October 12, 1916), piloted the inaugural flight of the St. Petersburg–Tampa Airboat Line on January 1, 1914, the first scheduled commercial airline flight in the world using heavier-than-air aircraft. In addition to preserving the legacy of Tony Jannus, the non-profit Society also offers financial assistance to college students pursuing studies in aviation and conducts an annual essay contest for high school students to encourage careers in aviation.
Document 14: Juan Trippe: Juan Terry Trippe (June 27, 1899 – April 3, 1981) was an American commercial aviation pioneer, entrepreneur and the founder of Pan American World Airways, one of the iconic airlines of the 20th century. He was instrumental in numerous revolutionary advances in airline history, including the development and production of the Boeing 314 Clipper, which opened trans-Pacific airline travel, the Boeing Stratocruiser which helped to pioneer cabin pressurization, the Boeing 707 which launched the Jet Age, and the Boeing 747 which introduced the era of jumbo jets (evolved from Air Force bombers, tanker and transport design, respectively). Trippe's signing of the 747 contract coincided with the 50th anniversary of Boeing, and he gave a speech where he explained his belief that these jets would be a force that would help bring about world peace.
Document 15: Gerard Brackx: Gerardus "Gerard" Brackx (1931, Ostend – 19 September 2011) was a Belgian businessman, pioneer of the Belgian travel business and founder of Jetair. His father was a Catholic businessman who owned a factory which produced washing machines and bicycles. Gerard was the seventh child out of nine. On the verge of World War II, his father died of pneumonia and Gerard had to start help working at the age of 16 to earn money for his family.
ground_truth: Amsterdam Airport Schiphol