iFly GPS Forum

I just received my iFly 700 and am immediately confused out of the gate. iFly seems to have redefined the term “course.” The Pilot/Controller Glossary defines course as “the intended direction of flight.” In other words, the course is the direction of the route line. The Glossary defines track as “the actual flight path.” The iFly course window should be labeled “track.” The Course Tape label is also confusing since nowhere on the tape is the course shown.

I’m not sure how to use the iFly to stay on course. I am used to flying a CDI needle. iFly has a Cross Track Error display, but it is digital and therefore unintuitive (negative for left, positive for right).

The Course Tape Ball is like following an ADF needle in no-wind conditions. It does nothing to get you back on course (back on the route line) and does nothing to tell you where the route line is. It would be much better if the guide ball acted like a Garmin bug by providing steering guidance to get you back on the route line. Another way would be to simply place the aircraft symbol on the route line on the moving map, but the precision of this method is affected by zoom level.

I am not sure of the meaning of the degrees number in the Turn window. This may be a digital readout of similar information to that of the Garmin guidance bug. If so, it would be great if the Course tape Ball used this information instead.

In summary, I’d suggest that the Course window be labeled “Track,” the Course Tape be labeled “Compass tape,” and the Course Tape Ball replaced with a Garmin type steering bug to guide the pilot back on course.

Please feel free to correct me if I’ve totally screwed up my assessment!

Hi Jon, thanks for the feedback. We have used the term "Course" meaning "Course over the Ground" - and I agree this could be better termed "Track", we will make this change in a future release.

The Course Tape instrument gives you a visual representation of the bearing you must follow to reach your next waypoint/destination. The Triangle on this instrument represents your Course over the ground (your track), and the ball represents the bearing you must follow to reach your waypoint. So if you keep these centered, you're heading is correct.

The Cross Track Error instrument will display in high resolution terms how far left/right of your originally planned route you currently are. If you wish to return to your route, simply turn a little more left/right as needed. I'm not familiar with how Garmin does this...but returning to the "Route Line" will often add unnecessary flying time...unless you are needing to squeeze through some mountain pass or skirt some airspace. In which case, the aggressiveness needed to return to your route will likely need to be pilot dictated.

Does this help?

@Jim,

Just about every GPS in existence display data in terms of couse over the ground (track). They are unaware of "heading" information, which is the direction your plane is actually pointed, to achieve a desired track. If there is no cross-wind, heading and track will the the same. In a cross-wind situation, the heading indicated by your compass or DG will not be reflected on a GPS. However this information is also not needed by a GPS - because the flight planning is only paying attention to your track, wind drift/heading is naturally compensated.

Toggling the iFly between Magnetic or True simply changes the relative point at which angles are being shown.

Thanks,

Walter

Hi Walter,

Thanks for the reply. I understand your logic. Your method of navigation will get you there. It is suitable for VFR, low precision flying. I am used to the more demanding method of flying where you must travel along a predetermined course (the route line). By doing this, ATC controllers will be happy (because you’ll stay on the Victor Airway), and the pilot knows that the flight path will not go over or through anything unplanned. Pilots get distracted. They fly off course. Your method of navigation, using the Course Tape Ball, does not enforce the need to get back on course, it allows the pilot to get off easy and fly a new course directly to the next waypoint. With other GPSs, we have all at times gotten off course and hit Direct-Enter to recalculate the leg’s course and fly directly to the next waypoint, but this is a sloppy, undisciplined way of flying. The iFly makes sloppy flying the norm by implementing a continuously calculating Direct-Enter feature.

You can use the Cross Track Error instrument to get back on course, but it is not easy. Say, for example, that you want to set up a 10 degree intercept. How can you do it when the Course Tape does not indicate the desired course? Most GPS show course, track and cross-track error with an HSI/CDI display, or course, track and steering guide bug with a compass tape display. To fly a 10 degree intercept is as easy as putting the track indicator 10 degrees from the course line. The iFly doesn’t depict the course – other than on the moving map – and there is no graphical depiction of cross track error.

The iFly is a marvelous GPS. I just wish that the steering guidance was more convenient for maintaining a course.

Jon