I had originally posted the following in the Pylon Racer forum in response to a request for building / flying feedback. After thinking about it, I decided that it would be a good post for the electric forum as well, and would be interested in comments.
I have been working on my second Gee Bee R3 from Hobby Lobby. The first was ordered in June 2008, and got shipped into me in July. I had pre-ordered and was in the first lot of 50 imported by Hobby Lobby. I ran into the same problems that many others did; poor documentation, pictures did not match the model, lack of assembly detail, etc. Largely, I had to "wing it" and depend on many years of model building to get it assembled correctly.
I must say that I was tremendously impressed with the quality and craftsmanship of the model, and the overall completeness of the kit, but more than a little concerned about the engineering details (or lack thereof) and the relative "lightness" of the construction.
My plan all along was to go electric, and I debated long and hard about whether I should install the firewall block off plate on the F1 former. I decided to leave it off (bad decision!) and go with the open lattice work for good airflow under the flight. I also decided to put in two triangular-shaped vents in the belly of the fuselage, to aid in venting the airflow. Should have made them bigger! I also built a pair of magnet mounting rings for the cowl (using rare earth magnets, with one ring glued to the front side of the F! former, and the other to the inside of the cowl) to aid in lining up the cowl with the backside of the spinner back plate. The cowl is simply not long enough to hit the reinforced mounting plates on the fuse, without the prop sticking way out in front of the cowl. I also reinforced the female mounting bracket for the canopy, as this looked a little weak and flimsy to me (boy, do I hate being right, but in this case I should have gone further).
The maiden flight of the Gee Bee was in late July 2008, and resulted in a catastrophic failure of the airframe and loss of the aircraft.
At take-off, the plane veered "hard left" (due to the high angle of attack of the wing, and P-factor influence) and headed for the tall grass at our field. I was able to correct in time, but the controls were way too sensitive and I was over-controlling (I used the original .PDF instruction manual posted on July 2008 which contained erroneous flight control surface settings), but I started to get it settled down. I was another 10 seconds into the flight when the canopy blew off the airframe (ripping off the mounting tab, and blowing off from FRONT to REAR
. The resulting buildup of air pressure in the airframe did a lot of nasty things to the interior, one of which ended up with the servo tray (for the elevator) popping off from it's supporting framework. Loose that, and you don't have any pitch control. The plane went in at a 20 degree angle. Ouch!
I documented the cause and effect nature of the failure and the resulting crash, and sent the report off to Hobby Lobby.
At this point in what is beginning to be a very long post, I must say that I can not say enough GOOD
things about Hobby Lobby; they are quite simply, one of the finest, most professional and ethical retailer that I have ever had the pleasure of dealing with. Bar none!
My letter to Hobby Lobby was assigned a case number, and was late picked up by Jay Graves, the President of Hobby Lobby. Jay got behind the note, and with a lot of help from Mike Hines in R&D, got the manufacturer to make some changes to the design, and between the manufacturer and Hobby Lobby, they agreed to replace the model at No Charge! Its not often that you meet good people like this, but in this crazy hobby / sport (?) of ours, you have a good chance of meeting them sooner rather than later.
I'm including some photos of the aftermath of last year's maiden flight, as well as some technical details of this year's build of the second Gee Bee. If there is enough interest in some of the construction details and photos from the second build, I'll be happy to do another post. I can also be reached at firstname.lastname@example.org
for individual request for info, so as not to bog down this thread or forum.