Well the weather finally cooperated and we flew the prototype Icon 2 on Sunday 3 Feb. This is a big airplane, 1,258 sq in, 150 in span. Radio equipment consisted of my trusty Futaba R148DF receiver, JR DS368 rudder, elevator and flap servos, and JR DS168 thin wing aileron servos and a 4 cell NiMH AA size 1700 mah battery pack. With about 3 ozs of lead in the nose the prototype came in at 79 oz ready to fly which put the wing loading at a hair over 9.1 oz per sq ft. Weather was heavy overcast, cool for Arizona (52 degrees F), very light wind. Field elevation at our flying field is 2500 ft MSL. A standard 12 volt winch with retriever and 250 lb test braided line was used to launch the airplane. Distance from the winch to the turn around was shorter than normal, about 170 meters, due to the need to work around some grass sprinklers that had been running all night. We elected not to launch the airplane for the first flight using the winch rather than risk damage during a hand launch. The first launch was spectacular to say the least! Using 10 degrees of camber with the tow hook about 1/8 of an inch ahead of the CG and moderate hold back on the winch, the airplane climbed absolutely vertically out of the launcher's hands. The launch was straight with slight wing bend so I kept my foot on the winch pedal through the climb and "bucket". The zoom was good and overall launch altitude was much better than normal considering the shortness of the line and lack of wind. While I didn't have my data logger installed for the flight I would guess the launch altitude at around 700 feet based on previous "eyeball calibrations" with the data logger. The first flight was spent checking out controllability, elevator trim settings, CG location, crow (butterfly) settings, etc. As a result, I wasn't really looking for lift and, given the weather conditions, didn't expect to find any lift. In spite of that duration on the first flight was about 8 min 50 sec. The airplane slowed down very well for landing with no tendency to fall off on a wing. During the course of the day we put a total of 7 flights on two airplanes (my prototype and a pre-production airplane)
My general impressions regarding the airplane are as follows. I was surprised with how nimble the airplane is in flight. This airplane doesn't exhibit the "wing heaviness" of other large sailplanes. Roll control and general flying qualities are very similar to the Pike Perfect. Secondly the airplane is responsive to rudder. Using coordinate rudder and ailerons I was able to perform some very tight (about 3 wingspan diameter) thermal turns. When forced the airplane will tip stall but recovery is quick. We intentionally spun the airplane and again recovery is quick and "hands off". As you might expect, the airplane has great legs and can really move out if you're looking for lift. While we weren't particularly searching for lift on Sunday, we did encounter a few very light patches of lift during the day. The airplane seemed to signal these well and a couple of tight turns in the lift produced solid climb indications. Our focus this last weekend was verifying structural strength and general airworthiness. All launches were performed pedal to the metal on the winch. Wing bend never approached any areas of concern. I am looking forward to doing some more serious thermal flying with the airplane this coming weekend and do plan on flying the airplane at the Southwest Classic Contest in Phoenix February 16 and 17. I am pretty impressed with the airplane. Phil Renaud
