Well I picked up a Zero at the LHS last week and didn't get around to building it until Saturday. Build time was no more than 4 hours. I chose NOT to cut the rudder loose. Instead I left it attached and made this a 3 CH bird (Aileron/Elevator only). This allowed me to use my cheap Focus 3 radio that I had been using in my stick... And frankly, I am tired of buying servos.
I used three different packs in flight testing:
8 Cell 2/3 AAA 300mah/nimh:
8 Cell AAA 720mah/nimh:
8 Cell 600AE:
All three packs were stacked 4 on 4 so they wouldn't fit in the provided battery holder. Instead I velcro'ed them to the fire wall inside the fuse. I managed to get the CG to fall right where the instructions said (with all three packs)... Perhaps the lack of the extra servo is what allowed the CG to fall in the proper area.
I made about 8 flights before packing things in -here is the experience:
All flights were ROG... Even though this tail dragger lacked a rudder I managed to point it into the wind punch the throttle and attain flight before it could ground loop. I think the key here is that I was flying 8 cells. With 8 cells the plane hops into the air in under 10 feet.
Very little trim was needed to get the bird to follow a nice glide path. Under power it wanted to point the nose up somewhat. I may drop the ailerons 1 mm to counter this.
The first flight was made using the AAA 720mah/nimh 8 cell pack. IMHO this pack gave the best performance... even thought the 600AE's dump more amps, the lighter weight of the 720/nimh allowed the similar vertical performance to the 600AE cells. The lighter weight of these cells also made for easier landings, the plane came in slower and lighter which is easier on the flimsy landing gear.
The next flights were made using the 8cell 2/3 AAA 300mah/nimh packs.. Flight durration was about 1/4 of the 720 pack. Climb was not satisfactory.
The next flights were made using the 600 AE's. Performance was similar to the AAA 720nimh pack. However, the 600's are heavy and as a result didn't net more vertical. The heavy bird was a chore to land even gentle landings resulted in the landing gear splaying way out.
All I had left was some 8 cell 600 AE packs. So I loaded up and went of to put the zero through it's paces. The Zero climbs out rapidly, has great inverted flight manners, and a moderate rate of roll. Rolls are, of course, not axial. Even without the rudder I could power through nice large loops, split s, stall, stall turns, blah, blah, blah, most all your inside manuever stuff..... Outside manuevers were less than thrilling compared to the Switch Back.
On the final landing with the 600 pack the wind died down and I brought it in without a headwind. The zero came in fast with the heavy pack and just would not slow down. My nice smooth touch down in grass resulted in a spectacular cartwheel as soon as the gear splayed out and stopped the forward motion imeadiately. I lost about 3" off of one of the wing tips but other than that the rest of the plane was in fine shape. The nice thing about the foam zero is that it started life looking like a FUGLY little foam wal-mart glider that was spray painted green..... you beat it up and and it retains it's FUGLY look quite well (some would say it's fuglyness is enhanced) so nothing is really lost and perhaps it is actually made better
One bad habit I noticed is that when pulling any sort of high speed high g type turn the plane would snap roll out un-predictably.... Same thing goes for dive recovery or tight split s type stuff... When recovering from a high speed dive and yanking back on the stick the zero would do some wierd sort of snap roll and go OC. The CG was set per the GWS specs but perhaps some experimenting will be necessary... I have a felling, though, that I may just be over stressing the control surfaces as they are pretty flimsy.
Things I'd do differently:
Stick with stock gear mounts but go with a higher profile thin (yes even more ugly) wheel - need more clearance and better roll out on less than ideal surfaces. I mean really this is one FUGLY bird who cares about scale.
Use 5 minute epoxy on control rod to elevator linkage and control rod to aileron metal to foam surfaces.
Mate/Glue elevator and linkage rod surfaces prior to installing the horizontal stab.
Use 5 minute epoxy on LE plastic wing mounts.
Don't put red zero stickers on bottom of wing. Just leave them on the top.. The plane is hard enough to see in flight.... Disorientation will be a big issue unless you are thinking each move through and stay focused while flying. Red zeros on top and bottom just make it much more difficult to tell which way things are pointed.
The fun factor is high and the FUGLY factor is out of this world ..... Grab a buddy, leave the combat streamers at home, grab some white glue, tape, and epoxy and go for blood!