ERushing
Well Known Member
Good Morning to the Braintrust.
This safety experience is unrelated to RVs other than I'm in the process of building one and have to fly something until I'm done. I'd like to get some feedback from the team on what might be the issue, if there is actually an issue and if I over-reacted. I don't have years & years of flying experience (this flight pushed me past 200 hours!) and don't know much about engines yet. I know the folks that peruse this site have both in abundance!
My wife and I flew the Diamondstar DA40 (edit) from The Dalles, OR to Richland, WA for dinner with friends last night - about an hour flight. The outbound flight was uneventful. After dinner, we loaded back up and began the short hop back to The Dalles. OAT at the time was around 100 deg F, admittedly a bit hot.
On the climb out, CHT's were fine, below 400 but the oil temp began rise as I climbed at ~100kts. This is not unusual, oil temp in this bird tends to run a bit hot. However, it quickly climbed into the yellow (>230) and was heading to the red. I pushed the nose over to 110 kts to increase airflow, slowing the climb. Temps still rising. Still full rich and CHTs were sub 400 deg. Altitude at this point was around 2500 ft. I was over relatively flat ground so I leveled to try to get the oil temp back in the green. No love. Began a slow descent. No love on the temps. Passing Prosser, there really isn't much between there and the Dalles. Going on was looking questionable. If I couldn't climb, we weren't going to make it home - big hills between Prosser and home. Made the command decision to return, stay the night with our friends and try the trip in the AM when OAT was a more reasonable 65 deg F. All the while, I was trying to get the temps back down. Eased the throttle back to ease the engine load thinking, less power, less heat but less airflow too...will this work? No...
To keep the oil temp in the yellow, I had to continue a slow descent back into Richland, dodging hills along the way back. It was a little stressful. But we made it back, landed successfully and parked.
This morning, we took off just after dawn with OAT around 65 deg F. Again, climbed at 110kts, oil temp rose to the yellow line and crested now and again. When it crested, I slowed the climb and brought it back into the green... Then continued climbing. In cruise and leaned to 50 ROP, it was finally nicely in the green.
What concerns me about this is that I've flown this airplane a lot. Most of my 200 hours are in this bird. I flew last year in the heat of the summer and ran into a similar issue but was able to resolve it by just slowing my climb and increasing airspeed.
I think I made the right decision but anyone think I over-reacted?
What could I have done differently to bring the oil temps down? I was running full rich to try to keep the CHTs down, thinking that high CHTs would lead to high oil temp.
I've brought the high oil temp to the attention of the FBO but they just smile and say that it's a tightly cowled airplane and it's just something we have to contend with. Any suggestions as to what they might do to bring the oil temp down?
I looked carefully at the cowl inlet and exit, no blockage, no bird debris, nothing...
Thanks for any advice and/ or suggestions!
This safety experience is unrelated to RVs other than I'm in the process of building one and have to fly something until I'm done. I'd like to get some feedback from the team on what might be the issue, if there is actually an issue and if I over-reacted. I don't have years & years of flying experience (this flight pushed me past 200 hours!) and don't know much about engines yet. I know the folks that peruse this site have both in abundance!
My wife and I flew the Diamondstar DA40 (edit) from The Dalles, OR to Richland, WA for dinner with friends last night - about an hour flight. The outbound flight was uneventful. After dinner, we loaded back up and began the short hop back to The Dalles. OAT at the time was around 100 deg F, admittedly a bit hot.
On the climb out, CHT's were fine, below 400 but the oil temp began rise as I climbed at ~100kts. This is not unusual, oil temp in this bird tends to run a bit hot. However, it quickly climbed into the yellow (>230) and was heading to the red. I pushed the nose over to 110 kts to increase airflow, slowing the climb. Temps still rising. Still full rich and CHTs were sub 400 deg. Altitude at this point was around 2500 ft. I was over relatively flat ground so I leveled to try to get the oil temp back in the green. No love. Began a slow descent. No love on the temps. Passing Prosser, there really isn't much between there and the Dalles. Going on was looking questionable. If I couldn't climb, we weren't going to make it home - big hills between Prosser and home. Made the command decision to return, stay the night with our friends and try the trip in the AM when OAT was a more reasonable 65 deg F. All the while, I was trying to get the temps back down. Eased the throttle back to ease the engine load thinking, less power, less heat but less airflow too...will this work? No...
To keep the oil temp in the yellow, I had to continue a slow descent back into Richland, dodging hills along the way back. It was a little stressful. But we made it back, landed successfully and parked.
This morning, we took off just after dawn with OAT around 65 deg F. Again, climbed at 110kts, oil temp rose to the yellow line and crested now and again. When it crested, I slowed the climb and brought it back into the green... Then continued climbing. In cruise and leaned to 50 ROP, it was finally nicely in the green.
What concerns me about this is that I've flown this airplane a lot. Most of my 200 hours are in this bird. I flew last year in the heat of the summer and ran into a similar issue but was able to resolve it by just slowing my climb and increasing airspeed.
I think I made the right decision but anyone think I over-reacted?
What could I have done differently to bring the oil temps down? I was running full rich to try to keep the CHTs down, thinking that high CHTs would lead to high oil temp.
I've brought the high oil temp to the attention of the FBO but they just smile and say that it's a tightly cowled airplane and it's just something we have to contend with. Any suggestions as to what they might do to bring the oil temp down?
I looked carefully at the cowl inlet and exit, no blockage, no bird debris, nothing...
Thanks for any advice and/ or suggestions!
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