Bill thanks for the info on the part number. Already have it located at Horizon site and will order it today. The Satio 56's I have are brand spanking new. I had planned on using two Satio 70's for the plane but it called for two 52's and a trusted hobbyshop owner was more than willing to sell me two more engines but assured me the 56's would be more than enough power. Like I said the rotation is not a must but it would be another bell to add to the P38.