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Exercise 5.7 - Real World Fuel and Cargo
brentonrule created the topic: Exercise 5.7 - Real World Fuel and Cargo
Hi Bob and team.
Well I am now totally bald. I was losing my hair now it has really fallen out.
I did this question to extend myself and see just how much I understood and am pleased to say I got close. At least with the process.
But I would like some clarification about the VFR assumptions. I used the TAFs at Roma and Emerald, I checked the RDS and also did checks on max TO and Landing weights/distances just to be sure.
I used a max height of 4500 feet so I used the 5000 feet performance with ISA+10 (the ARFOR and TAFs indicated CB and TS). No way I'd be going anywhere near them. Your answer uses the 10,000 ISA +10. I still got 2950kg but then I got different TAS etc etc
In the end I still got 260kg of Cargo.
Please let me know why as a VFR flight this would be undertaken at 8500 when TS and CB are forecast in the ARFOR. Is it becasue when VFR you can avoid them?
bobtait replied the topic: Re: Exercise 5.7 - Real World Fuel and Cargo
Congratulations for having the courage to tackle that question! The ARFOR has no mention of thunderstorms even though they are mentioned in the TAFs. The reason for going as high as possible is that a turbocharged aircraft like the Echo gets more efficient as height increases - better TAS for the same fuel flow. In practice, based on these forecasts, most VFR pilots would proceed with the flight while being aware that thunderstorms may be encountered. Since you are VFR, you will obviously see any cells along your track and, since they are forecast to last no more than 30mins, you should have no problem diverting around them. That's what your variable reserve is for.
Again, the question is far beyond anything you would be asked in an exam, but it does serve to illustrate how the pilot must keep the "big picture" in mind when flight planning. There are many variables to be considered.