I want to know what a "Walmart" GPS is. Walmart sells, amongst other brands, Garmin GPS units. These are among the best consumer GPS's available no matter what the name of the store is. They are very accurate and reliable.

Also, the notion that the speed reading is coming from the bungee launch doesn't hold up. If it did, then the speed would be constant. Instead, we see the speed increasing with the ongoing work on the model. Higher thrust engines, better aerodynamics, etc.

Granted, it would be nice to see speed readings from another method other than the GPS to back up the claims made by Neils, but most of the comments in this thread are to the tune of "Yeah, it's fast, but it's not THAT fast". You make it sound like it's a hopped up .40 size plane. I've seen videos of 200+ mph ducted fans, and this thing is considerably faster. 100 mph? Maybe, but until someone can prove Neils wrong, how about giving him the benefit of the doubt? In the real world of aircraft, 350mph is not that fast. I see no reason why this model cannot go as fast as Neils claims.

John