| Regimental number | 16003 |
| Place of birth | Sydney New South Wales |
| Religion | Congregational |
| Occupation | Carpenter |
| Address | Petersham, New South Wales |
| Marital status | Single |
| Age at embarkation | 18 |
| Next of kin | Father, William Armstrong, 35 Yule Street, Petersham, Sydney, New South Wales |
| Previous military service | 36th Infantry |
| Enlistment date | 8 February 1916 |
| Rank on enlistment | Driver |
| Unit name | Australian Wireless Squadron 1, Reinforcement 4 |
| AWM Embarkation Roll number | 22/16/2 |
| Embarkation details | Unit embarked from Melbourne, Victoria, on board RMS Mooltan on 22 August 1916 |
| Rank from Nominal Roll | Driver |
| Unit from Nominal Roll | 1st Wireless Signal Column |
| Fate | Returned to Australia 22 March 1919 |
| Family/military connections | Brothers: 2017 Sapper George ARMSTRONG, MM, 1st Field Company Engineers, returned to Australia, 15 May 1919; 14266 Sapper Herbert ARMSTRONG, 1st Australian Wireless Squadron, returned to Australia, 27 March 1918; 7439 Sgt Clifford ARMSTRONG, 13th Bn, returned to Australia, 31 January 1918. |
| Other details | Medals: British War Medal, Victory Medal |