Numerous achievements have been made recently by researchers in the areas of fiber laser beam combining and power
scaling. Industry has demonstrated multi-kW power from a single fiber amplifier, and a US national laboratory has
coherently combined eight fiber amplifiers totaling 4 kW. This paper will survey the recent literature and then focus on
fiber laser results from the Laser Division, Directed Energy Directorate of the Air Force Research Laboratory (AFRL).
Progress has been made in the power scaling of narrow-linewidth fiber amplifiers, and we are transitioning lessons
learned from PCF power scaling into monolithic architectures. SBS suppression has been achieved using a variety of
techniques to lower the Brillioun gain, including acoustically tailored fiber, laser gain competition resulting from multitone
seeding and inducing a longitudinal thermal gradient. We recently demonstrated a 32-channel coherent beam
combination result using AFRL's phaselocking technique and are focused on exploring the limitations of this technique
including linewidth broadening, kW-induced phase nonlinearities and auto-tuning methods for large channel counts.
Additionally, we have recently refurbished our High Energy Laser Joint Technology Office-sponsored 16-amplifier fiber
testbed to meet strict PER, spatial drift, power stability and beam quality requirements.