Let me know if any of this is useful. Please sign my guestbook or drop me an e-mail at handheldgps@hotmail.com, use GPS, APCalc, E6B or something relevant in the subject so I don't think it's spam.
If by chance you found this page directly instead of from Flight Computer for APCalc for Palm, let me reiterate a couple of points. There are many find E6-B programs already written for Palm OS. I would suggest a trip to www.palmflying.com would be worthwhile. One of my favorites is CoPilot by Laurie Davis.
APCalc, written by Mike Davis (not me), is a great calculator application. I use it as my main calculator. It is relatively easy to program small functions. I thought it would be handy to have some flight computer functions quickly and easily available on my primary calculator application. Thus, I programmed some of the formulas from Ed Williams Aviation Formulary page. Additionally, APCalc offers the ability to write your own functions for things that you may not be able to find elseware. I have some more information on this on the home page for this section.
I have quickly tried some example problems, but I have not thoroughly tested these functions USE AT YOUR OWN RISK!!! However, please let me know of any errors that you find. If you fix them or modify them, please let me know so that I can update the code here.
Quite honestly, I have spent quite a bit more time on this than I had anticipated and have not checked it as well as I would like and am putting the burden on you until I get around to it.
This is freely distributed. Feel free to beam or send my code to anybody. However, I am quite sure that there are some errors and bugs that I have not found and would rather you send somebody directly here to get the latest version.
First you need to load APCalc. You can get it at
www.palmgear.com. APCalc only allows you to use three functions until
you register it. I am not sure that the flight computer functions would
justify the purchase of APCalc, but I think that you will find it to be a very
useful application in its own.
Get the program into your Palm. The programs are text files that are
loaded into a Palm memo and are then imported into APCalc. Depending on
how you have things configures you cut and paste these files into the Palm
Desktop or an Outlook note.
There are two different versions:
The first version is my original file, palm/e6b.txt, (version 1.01 updated 7.14.2004).
Bruce Stafford,
http://members.cox.net/docstafford, created
a version with more of a general aviation orientation. It comes in two
separate files, one for the top set of keys and one for the bottom. Those
files are here: palm/E6B1s.txt,
palm/E6B2s.txt.
HotSync.
Go to the home page on your Palm. Find "Prefs." Select "Buttons"
from the pull down menu in the upper right corner. Choose APCalc for the
calculator.
Open APCalc, select menu -> Program, Load/Import. Make sure the "Import"
check box is selected at the bottom. Select E6B on the right, select a set
of keys on the left to send it to, and use tap on the dashed arrow on from right
to left in order to import it. Tap "Done."
When you get back to the main screen, you should see a D in the bottom left portion of the calculator screen. If you see an R, tap it and select "DEG." On the bottom right portion of the calculator screen, there is a small icon to select the set of programmable keys.
The choices are between wind components for the runway or calculating the heading necessary to fly to compensate for drift. If you input magnetic values, the results will be magnetic. If you input true values, results will be true. Speeds are in knots. A negative headwind is a tailwind.
RH, runway heading. For example, use 253 or whatever it may be for rwy 25 rather than just 25.
WD, wind direction
WS, wind speed
This allows you to calculate the winds aloft such as if you have a GPS and can get a value for GS and TRK. Speeds are in knots. HDG and TRK can either be magnetic or true, but must be the same. The resulting wind direction will be the same as the HDG or TRK.
This is for calculating, TAS, density altitude, and true altitude. If you just want density altitude, put in anything for airspeed. FE is for field elevation where the altimeter setting was taken. If the altimeter setting is greater than 500, than it is assumed to be metric -- thus, use either millibars or inches Hg. This is for calculating true altitude.
This calculates great circle distances given latitudes and longitudes. The format is in either decimal degrees or degrees and minutes. For example, 38 degrees 05.6 minutes would be entered as 3805.6. I changed the convention from Ed William's page to use the more conventional convention of western hemisphere longitudes and southern hemisphere latitudes being negative.
This is just something that I was playing around with. V is in knots and is groundspeed. TURN is the amount of heading change. Lead is the distance you must lead the turn to make the heading change. No account is taken for rolling into and out of the turn. I only calculated the tangent of the circle of a given radius for the bank angle. This is not meant for practical use, but just some illumination of the effects of bank and speed on turning radius.
This calculates standard temperature. If you put in an altitude of less than 500, it assumes this is a flight level. Thus an altitude of 250 is calculated as 25,000 ft.
These are just two built in functions assigned to keys. Most spreadsheets and scientific calculators have a variation of these two functions except that sometimes they are named in the perspective of angles instead of time. Thus, you might find dms instead of hms, but they operate essentially the same.
hms() converts a number into hour, minute, and second format. For example, if you are flying 180 nm. at 120 kts, and you plug 180/120 into a calculator, you will get 1.5. It will take you 1.5 hours to fly this distance. If you take hms(1.5), you will get 1.3 -- 1 hour and 30 minutes. In this case you could have just directly taken hms (180/120).
hr() has the opposite function. For example, if you wanted to use 1 hour 45 minutes for a calculation, you would simply use hr(1.45) which gives 1.75 hours.
John Bell Jan 22, 2006