C'mon guys! We're VFR pilots and SD is an
aid to VFR flight, NOT a Flight Management System (FMS).
We all learnt to fly by reference to a line drawn on a chart, a stopwatch attached to our clipboard, and some fairly rudimentary calculations, using
either a 'wizz wheel' or the 'max drift' method and
forecast winds aloft to establish an approximate magnetic heading to steer and ground speed (GS).
So, in this scenario, you're approaching your destination at 5,000 feet, so you have 4,000 feet to lose to get down to circuit height which, at a descent rate of 500fpm is 8 minutes. Your aircraft cruises at 100kts, but you have a headwind component of 10kts, so your GS is 90kts (1.5 miles per minute). 8 divided by 1.5 (or 16 divided by 3 makes the mental arithmetic a little easier) indicates that you need to commence your descent at a little over 5 miles out. It's not rocket science!
I don't mean to sound patronising, and if I have upset anyone, then here and now I apologise unreservedly, but as VFR pilots,
by relying too much on GPS, we are in danger of neglecting our responsibilities as airspace users and losing those precious skills learnt early on in our flying. Don't misunderstand me, I think GPS is a modern day miracle and an absolute godsend, especially if the weather turns against you. However, if we neglect those basic skills by which we all learnt to fly, we do so out our peril, because the day will surely come when we need to fall back on those skills to get us out of trouble.
Even as an avid SD user, my primary means of navigation is still a stopwatch and a chart, on which I have a course line drawn, annotated with magnetic heading, distance and an approximate a wind arrow. I also use all available radio navaids if appropriate. SD is my backup, especially if the weather turns bad, but if SD should fail (it never has, but could so easily do so through no fault if its own), I know where I am, how far and how long to my destination.
SD is a tool, and a very good one at that, NOT a replacement for basic flying/navigation skills. End of rant!
Mike
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Samsung Galaxy Tab A8 – Android 11.0 & SD 4.1.1.0
Huawei P30 – Android 11.0 & SD 4.1.1.0
PC – Windows 10 (Home Ed) Version 2009, Build 19045.6093, SD 4.0.2.0