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Today Sonex #1732 took to the skies for the first time from Bob White Airstrip (X61) in Apopka, Florida. The plane took off with no issues Temperature on the rear cylinders briefly hit 405 in the climb but I reduced power to 30"HG and shallowed the climb and they went down to about 390F in the climb. The plane did not appear to have a heavy wing, and the controls were smooth and even. I only flew for about 18 minutes, but I'm looking forward to a 60 minute flight tomorrow. The only mishap was a ground wire that worked loose for the turbo cooling system. That was repaired on the ground, hopefully I won't have another issue with that.

Here's the video:

https://youtu.be/Z8DZXn5cSAw

Congratulations! Beautiful looking Sonex!

YAY!

And I LOVED your daughter's (?) wonderment that it flew!

Thanks guys. It's was her 3rd birthday last week, she was really bummed that she couldn't go up with me. She wants to do "Gymnastics" in daddy's airplane.

Awesome! Congratulations!

Congrats!

My temps have moderated since putting a few flight hours on the engine. This morning with OAT at 33 I was able to climb to pattern altitude with 40" at 70-75 mph before backing off to 35"... and still climbing good.

Have fun...

Peter

pfhoeycfi wrote:Congrats!

My temps have moderated since putting a few flight hours on the engine. This morning with OAT at 33 I was able to climb to pattern altitude with 40" at 70-75 mph before backing off to 35"... and still climbing good.

Have fun...

Peter

Thanks for the info. I flew for 70 minutes today and tested 30", 32.5" and 35" of MAP. At 35" my EGT and CHT got a little hot. 1390 and 417 respectively. Below 33" I was able to keep the CHT around 390 and EGT around 1350. I am confident now that I'm Lean on the mixture and will do a 1/4 turn out before the next flight. I was able to hold 155mph with near zero wind at 35" and 3000', quite fast.

Looking forward to better cooling with a little more 100LL in the intakes. Will update.

pfhoeycfi wrote:Congrats!

My temps have moderated since putting a few flight hours on the engine. This morning with OAT at 33 I was able to climb to pattern altitude with 40" at 70-75 mph before backing off to 35"... and still climbing good.

Have fun...

Peter

Is 70-75 your Vy? You probably have not done that testing yet. I'm seeing Vy at 75kts, or 86mph. It is just as happy to climb at 80 - 85kts with not much change in climb rate. The higher speeds definitely help the cooling.

Bryan Cotton wrote:

pfhoeycfi wrote:Congrats!

My temps have moderated since putting a few flight hours on the engine. This morning with OAT at 33 I was able to climb to pattern altitude with 40" at 70-75 mph before backing off to 35"... and still climbing good.

Have fun...

Peter

Is 70-75 your Vy? You probably have not done that testing yet. I'm seeing Vy at 75kts, or 86mph. It is just as happy to climb at 80 - 85kts with not much change in climb rate. The higher speeds definitely help the cooling.

Haven't made it there yet. Flight 3 is Pitot Static Calibration in the EAA booklet. I've been climbing at 90mph to keep temps down.