Irwin, Herbert Carmichael (‘Bird’, ‘Bertie’) (1894–1930), athlete and aeronaut, was born 26 June 1894, apparently in Co. Dublin, one of four children of Thomas Frederick Nesbitt Irwin and his wife Elinor Emily Lindsay (née Carroll). The family subsequently lived in Dublin at an address on Merrion Square and at 42 Belmont Avenue in suburban Donnybrook. Herbert attended St Andrew's College, then situated at 21 St Stephen's Green, between August 1909 and June 1913. He was also a champion member of Clonliffe Harriers athletic club. In the first world war he was commissioned in the airship section, Royal Naval Air Service (RNAS). In 1916–17 Flight-lieutenant Irwin captained airships both in home waters and in the eastern Mediterranean.
After the war, in which the fledgling Royal Air Force absorbed the RNAS, he commanded R33 and R36, two of a series of airships whose most famous member, R34, flew to New York and back in early July 1919, the first transatlantic airship crossing. ‘Bird’ Irwin, however, had more terrestrial ambitions when he qualified for the athletic team of Great Britain and Ireland in the 1920 Olympic Games at Antwerp, Belgium. He competed in track events, coming second in the first heat, round one, of the 5,000 m race. In the final, however, he came twelfth. Although the Irish war of independence (1919–21) and a domestic feud between the GAA and the Irish Amateur Athletics Association (IAAA) had by then diverted much local attention from international sport, Irwin continued to represent Ireland and the RAF at running in spite of the confused political situation.
Under economic restraint, and with R34 succumbing to irreparable damage in January 1921, British airship development temporarily declined, with R38 being sold off to the US. On its departure for America, R38 too met with disaster, crashing in the Humber estuary. Irwin thus spent much of 1921–4 on ground duty and air ministry assignments till the revival of the airship, as an advanced mode of international transport and to offset German airship resurgence. Thus, the short-lived 1924 Labour administration (stealing Conservative fire) announced the imperial airship programme, which returned Irwin to active service. Posted in 1925 to the Royal Airship Works (RAW) at Cardington, Bedfordshire, he conducted flight experiments in R33 for super-airships capable of travel between Britain and its furthest possessions in India and Australia. While the ‘capitalist’ R100 designed by Barnes Wallis was commercially built by Vickers Ltd., the ‘socialist’ R101, designed principally by Vincent Richmond, was championed as a Labour government project for the state-owned Cardington works.
Under a less committed Conservative government, Irwin's experimental flights were succeeded by his commanding (1926–8) the RAF balloon training school at Larkhill on Salisbury Plain, Wiltshire. In 1929, with Labour's return to office, the R101 project was vigorously promoted again, especially by the secretary of state for air, Lord Thomson of Cardington, and Irwin was transferred back to the RAW as captain of the developing R101. Although his on-board authority was subordinate to that of Maj. George Scott, assistant director of airship development, Irwin was directly responsible for the airship and took an almost paternal interest in the outcome of late tests as it approached completion. As both airships competed to be ready for service, R101, replete with technical innovation and much-vaunted passenger accommodation, was test-launched 14 October 1929 with a cruise over London (two months ahead of its more modest rival), followed by a successful endurance flight to Scotland, Ireland, and Wales (17–18 November). Irwin's growing unease at damaged gasbags and excessive weight were expressed in his official reports. Pressure from Lord Thomson to have the R101 fully prepared in time to complete his visit to India ahead of the imperial conference in London (October 1930) exacerbated Irwin's anxiety about haste. Crew members shared his forebodings as urgency transcended caution.
Early October was deemed the latest possible departure time and, as trials continued, the weight problem was addressed in June by adding a gasbag bay amidships; greater length (at 777 ft / 237 m, R101 was the largest flying machine then in existence) afforded greater lift. In July–August R100 flew to Canada, putting R101 under more pressure for time. Torn surfaces remained a problem, and Irwin was not reassured by a certificate of airworthiness issued immediately before the flight to India, particularly as no full-power trials had yet taken place. He was now expected to carry these out en route. Unwilling to challenge authority and political enthusiasm, he lifted off from Cardington in leaden skies on Saturday, 4 October, with Lord Thomson and a distinguished entourage of expert passengers on board, fifty-four persons in all, heading towards France in celebratory mood. In spite of a gathering storm, no obvious concern was expressed in radio reports. Soon after 2.00 a.m., Sunday 5 October 1930, when Irwin may have been resting, the airship made two sudden dives, the second fatal, at Allonne near Beauvais, northern France. Striking the ground gently at about 2.09 a.m. the R101 burst into flames and collapsed on the edge of a wooded area. Lord Thomson and Flight-lieutenant Irwin, reported to have died at his post, were among the forty-eight killed, only six surviving. Accident investigators arrived and the French authorities conducted solemn funeral arrangements, British destroyers returning the dead to England for lying in state and a memorial service at St Paul's in London. A funeral train from Euston delivered the victims for burial (11 October 1930) in a common grave at Cardington church, where a memorial tomb was erected.
In a bizarre, much publicised incident of 7 October 1930, Irwin ‘spoke’ at a séance conducted in London by the Irish medium Eileen Garrett, explaining in great detail the structural causes of the R101 disaster. Although this phenomenon was taken seriously by some, the court of inquiry into the crash confirmed that no blame was attached to Irwin and concluded that the disaster was probably due to the combined effects of gasbag failure, spontaneous ignition, and severe weather.
Irwin married (1925) Olivia Marjorie Macdonald, daughter of Dr Charles C. Teacher of Hollington, Fareham, Hampshire, originally of North Berwick; they had no children.