shiny.ice Posted July 14 Report Share Posted July 14 Starting a new thread, I was putting some CTLS numbers in a random CTSW thread. Anyhow, went out and did some flight testing today, comparing flap settings. These are from 10k feet to 2-3000 feet, which takes about 12 minutes, flying to a specific IAS (with autopilot). I changed a setting roughly halfway. At first glance it seems like reflex works better at a slightly lower airspeed, but I think what it's showing is low elevation has a better ratio, which makes me think I want to try flying by TAS. Rather than simply measuring top of descent to bottom of descent, I'm using every second of the data, which lets me check the variance. Quote Link to comment Share on other sites More sharing options...
shiny.ice Posted July 14 Author Report Share Posted July 14 Measuring my climb speeds at various airspeeds. I had to write code to sort this one out. 500 data points at 100% throttle, 1200 points at 97% throttle. Quote Link to comment Share on other sites More sharing options...
Tom Baker Posted July 14 Report Share Posted July 14 If you are flying at less than gross weight the speed will typically be lower. You stay in the air longer at the lower speed, but the extra time in the air at the lower speed allows you to arrive at the same spot as the heavier airplane at the higher speed. Quote Link to comment Share on other sites More sharing options...
GlennM Posted July 15 Report Share Posted July 15 There are standard ways to take data for flight testing. I am not sure what they are, exactly. I vaguely recall that once you plot some of the data, you can obtain various speeds for your airplane through manipulations of the curves. Charlie Precourt used to offer information about flight testing procedures in his columns. I would search for those. Quote Link to comment Share on other sites More sharing options...
GlennM Posted July 15 Report Share Posted July 15 On 7/13/2024 at 9:02 PM, shiny.ice said: Is there a typo in the second speed section at 67kts? Are the 0 and -6 transposed? Quote Link to comment Share on other sites More sharing options...
shiny.ice Posted July 15 Author Report Share Posted July 15 20 minutes ago, GlennM said: Is there a typo in the second speed section at 67kts? Are the 0 and -6 transposed? The numbers aren't transposed- I started the glide test at 0 up high and -6 down low, opposite of the first and third tests. I wanted to ensure I controlled for that case- and I'm glad I did, it suggests -6 isn't actually better. Up next: testing e-prop takeoff techniques (eg stalling the blades, full power with brakes, etc). Quote Link to comment Share on other sites More sharing options...
shiny.ice Posted July 19 Author Report Share Posted July 19 Here are glide test numbers, alternating every 1000ft, so I can tease out the altitude differences. I also tried a different airspeed just in case I was "too slow" for -6 to benefit. On the first run I started -6° and then went to 0. I reversed that on the second run, starting with 0. Back to starting with -6 on that third run. So: -6 gives a longer glide with my configuration. Quote Link to comment Share on other sites More sharing options...
shiny.ice Posted July 19 Author Report Share Posted July 19 should I climb at -6° or 0°? at 78kts and 100% throttle or 97% throttle (912iS, so that's full power or eco-mode/closed loop), -6 is better. I'm deliberately normalizing the climb rather than show actual fpm values, there's no need to distract by thinking about specific climb rates. Quote Link to comment Share on other sites More sharing options...
FlyingMonkey Posted July 23 Report Share Posted July 23 So you show best glide as -6° and around 70kt? Quote Link to comment Share on other sites More sharing options...
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