Hi all!
I was wondering if anybody can enlighten me on the correct management of cruise FL changes. I'm familiar with the STEP CLIMB procedure to adopt a higher, more economical FL as fuel is burnt during cruise bit what about a LOWER FL? What is the correct, most professiona way of doing so?
I'm refering to FL constraints at WPs that are often encountered (especially in Europe).
As an example I often fly from EGNM or EGSS to LIMF and although the optimal FL is always around FL370+ there is on the route (wp XAMAB) a FL constraint for flights directed to LIMF. Unless a massive diversion is done I am therefore required to cross XAMAB at FL350. But XAMAB is around 150+ NM from the TOD.
How should I manage this? In my view the otions are three and I'm curious to know which one is the more correct, professional one
1. Set cruise at eg. FL390 the insert an altitude constraint of FL350 at wp XAMAB (bit in this case the plane goes in DESC mode when descending to the new cruise level)
2. Set the constrained FL (FL350) as cruise FL and then step climb to the required FL (eg.390) and the descend again
3. Set the required FL (eg. FL 390) as cruise FL and the change the cruise FL to the constrained one (eg. FL350) calculating when to start the descent manually
4. None of the above
Thank guys
Matteo Capocefalo MED1473