MSA
MSA is not a thing for a professional VFR flight. You are always bellow it. The marginal weather pretty much beeing the definition of bellow MSA. Masts are avoided by slowing down enought to be able to see and avoid them. Maps and HTAWS helps but are far from perfect. The general 500/1000 ft minum altitude and aviation maps/obstacle databases are a good way to not hitting anything static. Professional operators authorized to go bellow that need special procedures and training as there are increasing number of unchrated obstacles. (And a more limited number of options if the westher gets worse)
During a marginal weather VFR flight in a helicoper, MSA is only relevant when cosidering if transition (climb) to IFR is available due to icing and no aerofoil anti-icing. When flying off-route with IFR, MSA is of course the minimum altitude allowed (in a VFR to IFR transition one may need to be bellow MSA whilen flying unde IFR).
Last edited by mechpowi; 9th Mar 2024 at 12:53.