Sooo here’s to all of you who prefer a post rather than a story for a #flightplanning case.
Recently, I planned a #flight to GIG(Rio) which turned out kinda interesting, and not just #weather was to blame: the #airplane, a #b744, had a CDL item (A).
There’s basically two categories of technical defects that can affect a #plane.
MEL (Minimum Equipment List) items will directly limit/restrict some sort of operation (from seating capacity, navigation capability or “AOG”/aircraft on ground” anything is possible).
CDL (Configuration Deviation List) items, “only” affect #aircraft aerodynamic condition, reducing perfomance or increasing fuel burn.
I looked up the procedures and effects in the OM-B (operations manual part B — contains the plane related stuff), finding that a maintenance procedure was to be performed before every #takeoff. Therefore, I chose not the most fuel efficient alternate(B), but SBGR (Sao Paolo) where my #airline has own technical staff (as, otherwise, we’d be stranded after a diversion).
Additionally, the fuel burn would increase (due to less “clean” aerodynamic and more drag), reflected by a higher performance factor (C). My routine weather/NOTAM check was then followed by a thorough take-off and landing performance calculation, taking the CDL item into account (we use the same devices as our #pilots).
Now, finally route planning time and the next issue: even a freely-optimized minimum fuel / minimum time track (MFT/MTT) was late (E).
Also, the SIGWX promised quite some CB activity in the ITC (E, red route).
My min cost track (green) and the SAT (south atlantic tracks, yellow) were even slower and fcst yet worse.
So, analyzing charts, wind and temp fcst and satellite images (B), I eventually built up a route further west (E – blue; E – pink), which was to avoid the worst – and the turbulence mainly too – while arriving just in time (G).
So, I went downstairs to say hi to the #flightcrew (…and brief them that I’d taken that perfomance issues into account for my fuel figures / alternate planning too).
The only downside? I couldn’t just come along to Brazil 🇧🇷 🤷🏼♀️