Broad area travelling wave GaAlAs SQW optical amplifiers have been fabricated and characterised. Using a 600-mu-m wide and 1000-mu-m long double pass amplifier, 12 W of peak pulsed output power was achieved with a 0.08-degrees wide diffraction limited far-field lobe. Small signal gain of 31 dB was measured in a 400-mu-m wide active area device.