Genghis
I wrote the software that does all the calculations on the principle that you should never do twice what you can train a computer to do once. It was the mechanical wizzy wheel that I had forgotten how to use 30 years on, not the principles behind the calcs. If you take a look at my web app, you'll see it is comprehensive and thorough. The point of my post was simply to mention that with nothing more than access to email, you can check all your manual calculations and be sure of their accuracy and reliability. That was my only point. The embellishment about the toilets was a joke (i.e., didn't literally happen). I did however check my calcs by email in the planning room (not the toilets). I can recommend that you try out the app. You may find you can then give up on maintaining currency on the wizzy wheel. Even in expert hands, using the wizzy wheel is many times slower than the app. If you consider also the time it takes to manually extrapolate the wind and weather charts (in order to use the wizzy wheel), then unless you have plenty of time, there really is little point in doing it manually. A final point about using the email app (with command line arguments to specify the route etc) rather than a software graphical map interface to enter the route, is that the email approach is generally much faster (after a little practice). The central purpose of writing the app was to enable me to be efficient (saving time) yet still perform proper pre-flight planning with the minimum of fuss, and without being pinned to a specific device or software system (just email!). A year or so ago I posted it up on a web-server, free for anyone to use. So, please feel free to give it a go...or don't, no matter....just thought it may be useful/of-interest/etc to the private pilot forum...since in my observation, it's not uncommon to see (qualified) pilots taking off with little or no preparation...just the students seem to plan properly. Not having the software/device/kit readily to hand may be the mitigating factor in some instances, but most people at least have a phone capable of email these days...