ThacherD

Before I start this thread, I just want to say for the record that "I really enjoy the products that I have purchased from HobbyZone and Parkzone! Their RTF planes have helped me learn to fly and for the most part have been quality products." That said:

A couple of weeks ago while teaching my Father-in-Law how to fly, he became disoriented and crashed my Parkzone J-3 cub. The entire internal frame was crushed and the firewall demolished. I decided to keep the inner components as spare parts and purchase a couple of the J-3's. (one to fly and one just in case.) Last night I took one of the J-3's out of the box after my son's baseball game, put it together at the field I fly in, installed the batteries, did a range check, and was ready to fly! When I started the motor, the prop and plane seemed to vibrate more than the last J-3 I flew. Oh well, maybe a difference in motors. I tossed the plane into the wind and it gained altitude ever so gradually. It seemed to be underpowered. I figured that the vibration was the root of the problem, and landed the plane. (It flew like a Stuffed Walrus) I started to trouble shoot and discovered that the prop was way out of balance. I decided to go home and sand some material off the heavy side of the plane and try again later.
Today, with my newly balanced prop, I decided on my lunch break to try again. I got everything set up, and once again the plane's motor had a different audible pitch, the plane vibrated slightly, and the J-3 just seemed to be underpowered. When I was landing the plane I heard something that sounded like metal bumping plastic. (like something was rubbing the rotating plastic gear in the gearbox.) I decided to pop the cowl off and see what was going on inside the gearbox. It turns out that one of the 2 motor mounting screws had come lose during shipping and was floating free inside the gearbox. This was causing the the lack of power and was also causing the vibration and the sounds I heard when landing (The motor was only half secured and the gears were bouncing each other around!) After remounting the motor mounting screws, I put the plane back together and set up for flight. What a difference. This is the Parkzone J-3 I remember!! Good climbing power, and steady flight. What fun.
The Moral of my story is for all new pilots out there. (and even some old ones) Just because the plane says RTF (ready to fly), you should still check out all of the planes systems before flight. Make sure the pushrod linkages work, do a range check, check the motor, check the servo's, if there is vibration when the power is on find out why, make sure the prop is balanced, etc. Be sure to do a complete systems check before flight, You will be glad that you did. (I was lucky that I had the experience that I did with the J-3, or I probably would have crashed the plane!)
Once again, for the record, I love RTF's. They have taught me how to fly. Just remember that just because the box says its ready, it may not always be. My first Parkzone J-3 was ready to fly, my second one wasn't.

Any Comments or additional advice for new pilots on this thread is welcome!

Reddog177

I had the same experience with my PZ Cub. I had flown it a great many times, when one day it just lost power in the air? When I disassembled it, I discovered that both the screws had backed out of the motor far enough for the gears to disengage. There was no damage, so I screwed them back in, applied a dab of Goop to each screw and it's still flying.
Dick

wattman

[X(] Add me and my Cub to the loose motor screws after the 4th flight .
Lucky that the 2 screws stay in the gearbox .
I am very pleased and happy with my Parkzone Cub flying , so much fun