Originally Posted by T-Mar

Columbus Aelle was a tubeset employing a carbon-manganese (CMn) steel alloy in seamless, plain gauge tubes. The tensile strength, and consequently the wall thickness and weight, was between hi-tensile and chrominum-molybdenum (CrMo) steels. It's main advantage was that the brazing temperature range was wider than CrMo and therefore could employ less expensive, semi-automated brazing processes.

It was introduced for the 1978 model year and was typically found on mid-range racing bicycles and touring models. Often it was used for the stays and blades, in conjunction with higher grade main tubes, typically Columbus SL or SP. This reduced cost over a full SL frame while minimizing the weight increase. It was also manufactured in an Aelle R variant with butted main tubes.

Use of the Aelle tubeset started declining in the late 1980s, when Columbus developed economical, seamed, CrMo tubesets such as Matrix and Cromor, which took over the mid-range market.