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Hello IOPA!

On a recent ferry flight, I realized just how much cruise performance and running the Rotax at different power settings impacted my fuel endurance. I hope this post provides more insight into how to plan fuel stops on a multi-leg trip.
https://www.iconaircraft.com/2023/02/22/flight-planning-how-much-fuel-does-the-icon-a5-really-burn/?fbclid=IwAR2z60AiJqoXWIUFPrslbUpbEmyImLsMYFnvE6xC D56-lvLQZJGV8OZYecs

It would be nice to hear if your cross-country goals are to conserve fuel or time en route to each destination. It's all a matter of preference.

Blue skies,
Suzanne Clavette | ICON Marketing

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Suzanne,

I realize your heart was in the right place in pulling together this article but let me give a little constructive feedback.

1) The most important part: All this data is very much in the ICON A5 POH. The performance charts are good and were developed thoroughly via rigorous methods of flight test, and checked via rigorous methods of flight test, no need to provide other data or guidance this is how folks run out of gas.

2) Plan your flight and fly what you planned - An A5 customer ran out of fuel because he planned using the charts then flew well beyond the charts (RPM wise) for 90% of the flight. https://data.ntsb.gov/carol-repgen/a...port/99827/pdf

3) Lots of mixing and matching of the terms indicated and true airspeed. When talking about aircraft range and endurance it should always be discussed in True Airspeed. The only time that Indicated airspeed can be used to calculate range or endurance is at a Sea level standard day. Personally I've always hated that chart from the flight training manuals its super misleading unless you read the tiny little note at the bottom. However, unless you are cruising in death valley in the middle of winter on a 29.92, 15 deg C day "aka the unicorn day" its basically no value to reference indicated airspeed for range and endurance. True airspeed is what matters all the time this is why its on the charts. Those that have the G3X have true airspeed calculated for them real time, those without can either slip a wired digital thermometer through the canopy or calculate it with some accuracy by looking at winds aloft forecast for the temperature and a good old E6B flight computer (pro tip they come app forms now for free).

4) The title of the article was a little eyebrow raising and the way its phrased is basically saying the "charts are not good, but here is the real world data". This is 100% not true! The charts are good, but you need to factor in winds aloft.

5) You mentioned you burned way more than you thought you would. Were the winds stronger than you anticipated? Did you run at a higher RPM than you planned, fly at a lower altitude? The reason you burned more should be totally explainable and can and should be planned for during planning process. Would love to hear your thoughts on this.

For the crowd reading this:

Pro Tip:
Those charts look a little daunting I get it but the FAA makes us display them that way. But you really don't need the +20 temp or -20 temp portions of the charts if you can calculate density altitude. If you plan your flight properly by looking at winds aloft and getting the temperatures and pressures you can use that E6B app on your phone and calculate your density altitude. Then enter the middle column "Standard day temp" of the chart at that density altitude that will be your performance. Better yet that G3X will tell you the density altitude while you fly so you can cross check the charts.

Example:
You desire to cruise at 6,000 ft MSL. But the winds aloft forecast for temperature predict its going to be 15 deg C at that altitude during your flight and current altimeter setting is 30.12 inHG. So pull out that handy dandy E6B app and you find that at 6000 ft MSL at 30.12inHg and 15 deg C the density altitude is 7,148 ft. So enter the standard day columns of the chart at 7,148ft and at the RPM you want cruise at you will find your correct fuel burn (with a little vertical interpolation between 6000ft and 8000ft. No need to interpolate between the +20 and -20 ICAO temp days. That's the beauty of understanding density altitude. This Is the altitude the aircraft is actually performing at if it were a standard day (which it never is).

That all said I know you were well intentioned in writing this this so I commend your effort, but the bottom line is the charts are good, pilots should learn how to use them properly, and there is nothing magical about the A5 (its slow as hell) with respect to cross country, Now spin resistance on the other hand, that's pure Jon Karkow Magic.