Armstrong Siddeley Adder
| Adder | |
|---|---|
| Armstrong Siddeley Adder turbojet on display at the Rolls-Royce Heritage Trust, Derby | |
| Type | Turbojet | 
| Manufacturer | Armstrong Siddeley | 
| First run | November 1948 | 
| Developed from | Armstrong Siddeley Mamba | 
| Developed into | Armstrong Siddeley Viper | 
The Armstrong Siddeley ASA.1 Adder was an early British turbojet engine developed by the Armstrong Siddeley company and first run in November 1948.