I took this service which is a domestic PSO route in Portugal from Portimao to Cascais and back. They operate a Dornier 228 18seater aircraft twice a day, the day I arrived at Portimao aerdrome the flight had a healthy passenger load operating nearly full. The security procedures here are conducted by the local police. Not long after the aircraft landed we were boarding and without much fuss on our way. This airlines provides a bus stop like service the route is Portimao - Cascais - Viseu - Vila Real -Braganca which is the most northerly point. Cascais is fairly close to Lisbon, and I believe a shuttle bus can be arranged to the capital upon request. Cascais Airport is frequently used by executive jets, and therefore the facilities are more enhanced than Portimao. On the return two days later, the aircraft arrived with most passengers disembarking at Cascais as a result there was only 4 passengers taking the last segment southwards. On arrival at Portimao, there looked again a reasonable passenger load awaiting the northbound schedule. This airlines obviously provides an important link across the country saving many road hours. The duration of this flight was about 25 mins, as we didn't fly too high the views were great and the trip was one of the most pleasurable flying experience i've had in a long time. So nice to travel on a small plane with no massive security delays which you get from big airports these days.