ORIGINAL: turbo.gst
The original EU-1 was published in the April '78 MAN. It was presented with two different airfoils (15% and 17%). The 15% wing had better spin characteristics. The 17% flew smoother. They were thinking of adding stall strips to the 17% wing. Wanye Ulrey flew the 17% version in his 5th place finish at the 1977 Masters. The article used every conceivable method to encourage 'careful' selection of materials to keep weight down to 11 lbs fueled. I am not sure what actual changes went into the EU-1a.
The Mama Mia was published in the Nov '80 Model Builder. Joe Bridi mentions that he was impressed by the EU-1's flying charateristics and ability to fly the FAI pattern. He then started to think about designing a larger pattern ship. He was also trying to fly at 11 lbs but the plans show 11 lbs 2 oz.
I'm not sure when the EU-1a came on the scene.
turbo
I campaigned an EU-1A for three seasons back in the 80's. This was the epoxy fuse/foam wing version. As you mention, it was REALLY hard to keep it in the 10 lbs. range. With a Rossi .61 screaming its guts out, it flew well, but I was often downgraded for manuvers which were thought to be too small. I believe the size of the EU-1A gave the perception the manuvers were too small! Still the best rolling aircraft I have ever flown. With a modern 1.20 pumped engine, I believe it would still do well in the lower classes today. I had never seen the Momma Mia until this thread started. I see it has the ubiquitous fiberglass canopy/pipe cover that all of Bridi's later pattern designs had. Again, with a modern 1.20 or 1.60, I bet it would do well in lower class pattern. May I say this is a fantastic thread and I have had much pleasure in reading and responding to...