Yep. I flew choppers in Colo in the Army and our lifting capacity was greatly reduced on hot days at 5,000 ft base elv. It's the same for glow also, tuning changes in hot or cold weather high/low humidity
ORIGINAL: Zeeb
Hmm.....
It's called "density altitude" and combines a field elevation, ambient temp, barometric pressure and although not normally figured a lot, humidity.
On full scales, they are rated for performance based on a "standard day" which is 59 degrees F, barometer at 29.92 and Sea Level. Change those parameters and the performance changes. Generally speaking; raising the temp decreases performance. Raising the field elevation decreases performance, raising the amount of water in the air (humidity) decreases performance because it displaces air molecules.
So it would seem you were mis-tuned if your model flew better with it being a hotter ambient temp and a lower humidity.
Please remember that you may not see a lot of difference in the model as the weather changes but it can make a HUGE difference in a full scale operating in mountainous areas in the summer...
