Sunday 2 September 2012

Programming routes into SkyDemon and AirNavPro on the iPad via email

In my previous post, I described the main steps I follow when planning a VFR flight. As an example, I planned my upcoming route from Prestwick to RAF Leuchars where I'll be exhibiting my Bulldog on the static display in the 2012 Airshow.

In my VFR flight planning, I use a mix of "the old" (map, ruler, etc) and "the new" (automated PLOG computation via iNavCalc, plus other internet resources for NOTAMs, etc., all accessed via my Samsung Galaxy S2 smartphone).

A notable omission from that post was the use of my iPad in the cockpit. I'll cover that topic now.

Like most private pilots these days, I use my GPS device as my primary nav reference on-board. Specifically, I use my (IFR-approved) Garmin GNS 430. Owing to the inconvenience of programming non-standard waypoints on this device, I tend to use the "Direct-To" function between successive major (standard) waypoints to monitor the progress of the flight, and mostly to ensure I avoid controlled airspace. Even when monitoring progress on the Garmin 430,  I fly the nominal headings as prescribed by my pre-planned PLOG (see STEP 2 in previous post), making ad hoc corrections for wind (that differs from the forecast in the PLOG), and making routine visual reference to my physical chart (line on map, STEP 1 in previous post). I also routinely look out the window for the corresponding relevant ground features (it is VFR, after all).

That said, there are some powerful, feature-rich VFR flying apps available on the iPad. Notably, SkyDemon and AirNavPro, which are two of the most popular apps (at least here in the UK and Europe).

...but first, a couple of caveats

 I do not use the iPad as a primary nav reference in-flight, owing to the fundamental lack of robustness of the iPad (very much a consumer media device, not a true avionics device). I do, however, use the iPad flying apps for specific functionality that is very handy but not absolutely essential i.e., I can continue flying my route even if my iPad falls over (as it tends to do, every so often).

Also, a non-insignificant consideration is that there is simply no room in my Bulldog cockpit to accommodate my iPad in permanent view throughout the flight. Instead, I have to store it between the seats and take it out to view on occasion. 

What I use SkyDemon for

I use SkyDemon on my iPad for the following:
  • Getting a list of frequencies for my route when I'm confident I will not require any IFR materials (in which case, I use full JeppView trip-kits). Although I find the SkyDemon export to be slightly clunky (since it does not render directly in PDF format), it is more convenient than JeppView for quickly retrieving a list of comms frequencies for purely VFR purposesI do not use SkyDemon for airfield plates since it provides only the relatively crude AIP files.
  • Vertical nav sanity-checking. The "virtual radar" function is visually slick, and helps me to verify that my planned altitudes do, in fact, avoid CAS and terrain, as intended. 
  • A backup GPS-enabled moving-map when in-flight. I basically "play" with this in-flight, but do not rely on it due to the fundamental non-robustness of the iPad. That said, SkyDemon helped me considerably on my recent flight from EGNS to EGPK (see opening paragraph to previous blog post) when Prestwick approach asked me to "report Dalrymple". I couldn't find "Dalrymple" on my physical chart, it wasn't on my Garmin 430, but it was on the SkyDemon map, so I quickly adjusted my heading and flew direct to Dalrymple using the SkyDemon moving-map.

What I use AirNavPro for

I use AirNavPro on my iPad for the following:
  • A backup GPS-enabled  moving-map when in-flight. Again, I just "play" with this in-flight, but do not rely on it due to the fundamental non-robustness of the iPad. However, because AirNavPro incorporates the UK CAA 1:500k charts, I find it helpful for increasing situational awareness since I can quickly compare "one-to-one" with my identical physical chart. I somehow find this more natural than the SkyDemon vectorised charts (visually very attractive and appealling, as they are). That said,  AirNavPro wouldn't have helped me in locating Dalrymple !

Loading routes on to the iPad

Assuming I've already generated my route via iNavCalc's email interface, I will have received an email with the following attachments (as described in detail in the previous post, repeated here for convenience):

In the previous post, I described in detail the "PLOG_....pdf" and the "MET_...pdf" attachments. I'll now describe the "ROUTE_....gpx" attachment. 

As the filename suggest, this is just an XML file (in the open-standard GPX format) which encodes the route.  It is almost trivial to load this file into the iPad using either SkyDemon or AirNavPro. Here's how:

Within the iPad email app, click on the "ROUTE_....gpx" attachment. The GPX content will be displayed in the main window (human-readable XML script), and, moreover, can be "opened in" any supporting installed app (as per the usual iPad functionality for embedded email attachments), as shown below:

Selecting SkyDemon, will load the route as follows:

Likewise, selecting AirNavPro, will load the route as follows:

That's really all there is to it !

In summary

So, to recap from the start of the previous post to the present:

Starting with a simple iNavCalc email:

I can construct an entire route based on a list of waypoints (specified in a natural manner i.e., reading-off from the line I've drawn on my paper chart), then import the route in to my chosen (GPX-compliant) iPad flying apps in a couple of clicks. Viewed in this way, iNavCalc can be considered as a natural, efficient, shorthand way of creating routes for your favourite iPad flying apps. 

Leuchars airshow, here we come !


  1. I was so surprised when I start programming on ipad it was an awsum experience.