Hi All

I contacted support recently regarding an issue that occurs when flying at altitude. However, it seems that there are diverging opinions on how SD should handle individual legs and their corresponding TOC/TOD pairs.

Aircraft: Robin 401 standard descent rate 300 - 1000 ft / min

Recently I flew to Sion (Switzerland) which requires to cross the alps a 12 - 14k/ft. Sion Airport is situated in a Valley flanked by by mountains about 10k ft tall. The circuit is at 3000ft. After crossing the highest range one must descend gradually to the pattern altitude.

Hence, each leg has an altitude defined. I.e. 14k, 12k, 8k, 6k, etc. The rate of descent is about 500-800 ft/min.

The vertical representation in SD looks as follows.

After reaching the TOC, SD represents the descent based on the standard rate of descent configured in the AC profile resulting into a straight line drilling through the alps.

Reply from Support:

If a climb or descent is needed in order to achieve the planned altitude for a leg, the climb or descent parameters of the aircraft profile are used, not the cruise profile you have selected for the leg. In this example, the descent has to begin almost immediately after the TOC in order to descend to the next planned level, and then to the landing, using the specified descent rate/airspeed. You will see that the top of the descent will change if you increase/decrease the descent rate in your aircraft profile.

This might be OK if you fly at 3-4k ft but makes no sense when flying at 14k ft.

In order to get a more or less correct representation, one has to set the rate of descent to 3000ft/min. Unfortunately a Robin is not a Jet.

In my opinion the altitude of each leg in conjunction with the ACFT parameter is relevant for the correct representation of the flight profile.

Any other opinions?

Lorenzo