| Regimental number | 14266 |
| Place of birth | Sydney New South Wales |
| Religion | Congregational |
| Occupation | Clerk |
| Address | 35 Yule Street, Petersham, New South Wales |
| Marital status | Single |
| Age at embarkation | 22 |
| Next of kin | Mother, Mrs Ellen Armstrong, 35 Yule Street, Petersham, New South Wales |
| Enlistment date | 6 December 1915 |
| Rank on enlistment | Sapper |
| Unit name | 1st Australian Wireless Squadron |
| AWM Embarkation Roll number | 22/16/1 |
| Embarkation details | Unit embarked from Melbourne, Victoria, on board RMS Morea on 30 May 1916 |
| Rank from Nominal Roll | Private |
| Unit from Nominal Roll | 1st Wireless Signal Squadron |
| Fate | Returned to Australia 27 March 1918 |
| Family/military connections | Brothers: 2017 Sapper George ARMSTRONG, MM, 1st Field Company Engineers, returned to Australia, 15 May 1919; 16033 Dvr Harold ARMSTRONG, 1st Australian Wireless Squadron, returned to Australia, 22 March 1919; 7439 Sgt Clifford ARMSTRONG, 13th Bn, returned to Australia, 31 January 1918. |