Air Marshal Sir Thomas Walker Elmhirst, KBE, CB, AFC, DL (15 December 1895 – 6 November 1982) was a senior commander in the Royal Air Force in the first half of the 20th century and the first commander-in-chief of the Royal Indian Air Force upon Indian independence in August 1947, in which post he organised the funeral of Mahatma Gandhi following his assassination in 1948. He later became the Lieutenant-Governor and Commander-in-Chief of Guernsey from 1953 to 1958.

Thomas Elmhirst was born on 15 December 1895 to Reverend William Heaton Elmhirst (b. 1856) and Mary Elmhirst (née Knight; b. 1863),^[1][2] a landed gentry family in Yorkshire, where the family seat is Houndhill. He was the fourth of eight boys and had one younger sister. The children were:

• Captain William Elmhirst (1892–1916), killed on 13 November 1916 while serving with the 8th Battalion East Yorkshire Regiment during the Battle of the Somme^[3]
• Leonard Knight Elmhirst (1893–1974), a noted philanthropist and educational reformer who married Dorothy Payne Whitney^[2]
• Second Lieutenant Ernest Christopher "Christie" Elmhirst (1895–1915), killed on 7 August 1915 while serving with the 8th Battalion Duke of Wellington's (West Riding Regiment) during the Gallipoli campaign^[4]
• Thomas Elmhirst (1895–1982)
• James Victor Elmhirst (1898–1958)^[1]
• Richard Elmhirst (b. 1900)^[5]
• Alfred O. Elmhirst (1901–1995)^[5] of Houndhill
• Irene Rachel Elmhirst (b. 1902)^[5]

Elmhirst studied at the Royal Naval Colleges at Osborne, Isle of Wight in 1908, and at Dartmouth in Devon.^[6]

Elmhirst married firstly Katherine Gordon Black, daughter of William Black, on 16 December 1930,^[9] and had two children before Katherine's death in 1965:

• Roger Elmhirst (1935–1999)^[10]
• Caroline Jane Elmhirst (b. 1932),^[10] who married Michael Frazer Mackie^[7]

On 30 October 1968, he married Marian Ferguson (née Montagu Douglas Scott), widow of Colonel Andrew Henry Ferguson. Marian was the daughter of Lord Herbert Montagu Douglas Scott and Marie Josephine Edwards, and the granddaughter of The 6th Duke of Buccleuch and Lady Louisa Hamilton. From Marian's first marriage, she was the paternal grandmother of Sarah, Duchess of York, and maternal great-grandmother of Princess Beatrice of York and Princess Eugenie of York. Together they lived at Dummer Down House, at Dummer in Basingstoke, Hants, her dower estate from her first marriage.^[11]

Thomas Elmhirst died at Dummer, Hampshire, on 6 November 1982, in his 87th year. He was survived by his second wife, and his children and grandchildren from his first marriage.^[7]