Olympic Airlines (Greek: Ολυμπιακές Αερογραμμές , "Olympiakés Aerogrammés" – OA), formerly named Olympic Airways for at least four decades, was the flag carrier airline of Greece.
 The airline's head office was located in Athens.
 The airline operated services to 37 domestic destinations and to 32 destinations world-wide.
 The airline's main base was at Athens International Airport, with hubs at Thessaloniki International Airport, "Macedonia", Heraklion International Airport, "Nikos Kazantzakis" and Rhodes International Airport, "Diagoras".
 Olympic Airlines also owned a base at London Heathrow International Airport.
 By December 2007, the airline employed about 8,500 staff.
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.
Air India is the flag carrier airline of India.
 It is owned by Air India Limited, a government-owned enterprise, and operates a fleet of Airbus and Boeing aircraft serving 90 domestic and international destinations.
 The airline has its hub at Indira Gandhi International Airport, New Delhi, alongside several focus cities across India.
 Air India is the largest international carrier out of India with an 18.6% market share.
 Over 60 international destinations are served by Air India across four continents.
 Additionally, the carrier is the third largest domestic airline in India in terms of passengers carried (after IndiGo and Jet Airways) with a market share of 13.5% as of July 2017.
 The airline became the 27th member of Star Alliance on 11 July 2014.
Air Mauritius Limited, operating as Air Mauritius, is the flag carrier airline of Mauritius.
 The airline is headquartered at the "Air Mauritius Centre" in Port Louis, Mauritius.
 Its main hub is Sir Seewoosagur Ramgoolam International Airport.
 The company is the fourth largest carrier in Sub-Saharan Africa, and has an important standing in the European, African, and Indian Ocean region markets; the airline won the “2011 Indian Ocean Leading Airline Prize”, making it the seventh year in a row for it to win the award.
Aer Lingus, ( , an anglicisation of the Irish "aerloingeas" meaning "air fleet") is the flag carrier airline of Ireland and the second-largest airline in Ireland.
 Founded by the Irish government, it was privatised between 2006 and 2015 and it is now a wholly owned subsidiary of International Airlines Group (IAG), the parent company of British Airways and Iberia.
 The airline's head office is on the grounds of Dublin Airport in Cloghran, County Dublin, Ireland.
Dermot Mannion is the former Deputy Chairman of Royal Brunei Airlines and former Chief Executive Officer of Aer Lingus.
Thai Airways International Public Company Limited, trading as THAI (, Thai: บริษัท การบินไทย จำกัด (มหาชน) ) is the flag carrier airline of Thailand.
 Formed in 1988, the airline has its corporate headquarters in Vibhavadi Rangsit Road, Chatuchak District, Bangkok, and primarily operates out of Suvarnabhumi Airport.
 THAI is a founding member of the Star Alliance.
 The airline is the largest shareholder of the low-cost carrier Nok Air with a 39 percent stake, and it launched a regional carrier under the name Thai Smile in the middle of 2012 using new Airbus A320 aircraft.
Pieter Elbers (born 11 May 1970) is a Dutch airline executive, the current President and CEO of the flag carrier airline of the Netherlands, KLM.
Nepal Airlines Corporation (Nepali: नेपाल वायुसेवा निगम ) is the flag carrier airline of Nepal.
 Its head office is in the Nepal Airlines Corporation (NAC) Building in Kathmandu, and its main base is Tribhuvan International Airport, Kathmandu.
 The airline was established in July 1958 as Royal Nepal Airlines Corporation (RNAC) to be Nepal's first airline.
 The airline's first aircraft was a Douglas DC-3, used to serve domestic routes and a handful of destinations in India.
 The airline acquired its first jet aircraft, Boeing 727s, in 1972.
 As of May 2017, the airline operates a fleet of ten aircraft.
Nicaragua Airways is the potential future national flag carrier of Nicaragua.
 Its main base is Augusto C. Sandino International Airport, Managua.
 It is the first time in 20 years that Nicaragua will have a national flag carrier, after Aeronica ceased operations in 1991.
 Since then, the flag carrier status was awarded to Nicaragüense de Aviación also known as NICA Airlines.
 Several airlines had tried to become the Nicaraguan flag carrier like CAAL (Central American Airlines), SANSA (Servicios Aereos Nicaraguenses S.A.) but none of these survived a year.
 Today even NICA Airlines (6Y) is registered as the national airline of Nicaragua, the only international flight it operated once (Managua to Miami) and is done under the TACA code (TA) as a full TACA Airlines flight.

Question: Dermot Mannion was the former CEO of which flag carrier airline of Ireland?
Answer: Aer Lingus