Sorry Guys, Thanks for all the really great responses but, false alarm. After every sail, I usually remove the batteries from the GPS and had assumed that this would "zero" out all the active data. The 34.4 mph bothered me so much that I just had to dicsover the true validity of this figure. I also didn't want to rely on a device that could be that inaccurate. So, I zero'd everything out manually, took the batteries out then put them back in. After driving around the block (at 27 mph top speed), I removed the batteries, put them back in and "low and behold," the maximum speed still registered at 27 mph. My bad, but thanks for your help anyway.
The only downside is that I'll never know how fast "Frenchie" (the other solo sailor on the other H16) and I were going. He's the guy that made wings (training wheels)
for the H16 but stopped for health reasons. This time last year, it was assumed that he would not be alive this time this year and that he would never sail again. Well, I told him that he was going to get a chance to sail again and if I ever caught hiim on the water, I was going to "smoke" him. I just want to say that, "he did a pretty good job for a man that's supposed to be dead. I don't think my boat has ever gone that fast, even with a crew.