Originally Posted by
gettinbumped
Well your first issue is that Sabre is planning you at .765 and you're flying at .80 for ATC, crossing, home leg, just feel like it, so of course it's going to be off. The Sabre flight plan has some data to tell you roughly how much so at least you can take a wag at how much more gas you're going to burn.
But the Howgozit is not then rendered worthless. Pull up another one several fixes down line and you will see that it has recalculated your landing fuel and time based on what you've actually been flying. Better still, contact dispatch and tell them you're flying .80 and a different flight attitude and have them re-run your FP. Then pull up a new Howgozit and it will give you the accurate numbers.
Not sure why the disdain for it. It's a good tool for the tool chest and eliminates the multiple math errors I saw guys making before it existed
Actually,
The Howgozit recalculates each additional fix at the original SABRE flight planned speed and altitudes.
So you can ask for another HOWGOZIT after each fix, and it will recalculate based on the filed SABRE flight plan speed AND altitude.
If you are planning to go .80 (example), or at another altitude (rides), you need to manually send dispatch a message for them to rerun the flight plan and send you a .80/FL360 howgozit - when they do, that will update the SABRE flight plan in the system and it will THEN give you a valid howgozit.
But you are incorrect - it does NOT update what you've changed in the FMC (speed or altitude) - but simply "recomputes".
Have you ever noticed an excessively high number UAL app flight updates updating the arrival time so much on an inbound flight?
The reason for that is that the flight plan was .76 (example), but the guys are going .81 to be on time (A:00). After each fix or two, when the arrival time is updated (fix X distance remaining X SABRE speed of .76), the app "updates" the arrival time - based on flying the remaining flight at .76.
This "can" be incredibly annoying for our customers who's family is waiting for them and the app keeps updating the arrival time (getting there different than when they looked 5 hours ago). As the aircraft gets closer and closer, the distance remaining is so small that even when you go .81 the times eventually become the "estimated" arrival time.
As a result, if they don't recheck the arrival time on the app, the may not leave for the airport in time.
As a "technique", most L-UAL guys figure out what speed they want for the tracks, get the clearance from Gander/Shanwick - and then have dispatch rerun a new howgozit prior to coast out.
That way (five +/- hours from touch down), the UAL SABRE automated position reports can keep customers/opps/SONIC up to date with a very accurate estimated arrival time.
Nice technique IMHO - but it can increase the work load on an already overloaded dispatcher.