Flying_Monkey
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- Joined
- Sep 22, 2014
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I took a mountain flying course out of San Diego this weekend. First of all, SO MUCH fun- flying up and down canyons, learning about winds, crossing ridgelines, landing at airports with terrain around them, and flying to a high DA airport at the end. I learned a ton and it was a real confidence builder.
We departed Big Bear airport and the OAT was around 25 or 27 C. I leaned during a full power runup for best power. The DA was reported on the ASOS to be 9000 feet at the 6700 foot elevation airport. Upon takeoff, I noticed on my JPI 830 that the CHTs were really hot- 430+. I have the alarm at 425 so 3 cylinders were causing the alarm to flash. I realize there are 3 things you can do- pitch the nose down for better cooling, throttle back, or enrichen the mixture. All of those options compromise the climb performance.
So the question is: How do y'all manage high DA situations and CHTs- do you just say screw it we need the climb performance the engine is going to run really hot for 5 minutes? I feel like we had ok climb performance- we weren't at max gross but we did fill up to full fuel to try to get as close as possible since this was a learning exercise as part of the training. Climb rate was 300-500fpm and were were probably 200 under gross. Maybe go with a richer mixture once clear of obstacles and if the winds are not strong?
In this case, I did enriched the mixture once the CHTs were so hot and eased off the climb rate. I climbed in small step/level off increments to gain altitude and then cool a little.
We departed Big Bear airport and the OAT was around 25 or 27 C. I leaned during a full power runup for best power. The DA was reported on the ASOS to be 9000 feet at the 6700 foot elevation airport. Upon takeoff, I noticed on my JPI 830 that the CHTs were really hot- 430+. I have the alarm at 425 so 3 cylinders were causing the alarm to flash. I realize there are 3 things you can do- pitch the nose down for better cooling, throttle back, or enrichen the mixture. All of those options compromise the climb performance.
So the question is: How do y'all manage high DA situations and CHTs- do you just say screw it we need the climb performance the engine is going to run really hot for 5 minutes? I feel like we had ok climb performance- we weren't at max gross but we did fill up to full fuel to try to get as close as possible since this was a learning exercise as part of the training. Climb rate was 300-500fpm and were were probably 200 under gross. Maybe go with a richer mixture once clear of obstacles and if the winds are not strong?
In this case, I did enriched the mixture once the CHTs were so hot and eased off the climb rate. I climbed in small step/level off increments to gain altitude and then cool a little.
