Originally Posted by
michael wood
I am using a 4.8 volt 2000 nimh for the ignition and a 6 volt 2500 nimh battery for the receiver mounted up front by the fire wall the engine mount I am using are large T type don't know the name
You should seriously consider increasing the capacity of the flight pack.
At worst put in two 6V 2500 NiMH packs and connect them in parallel to give you an effective 5000mA 6v pack.
You are running EIGHT SERVOS on this plane plus the receiver.
A single digital servo can draw 2000mA as it approaches stall. Typical momentary bursts are in the 1000mA to 1200mA range as the servo reverses direction.
Likewise a single high torque analog servo will draw up to 1500mA as it approaches stall and typically hits 750mA during direction changes.
A single 6v 2500 pack is begging for brownouts even if your flight times are fine.
This is a giant scale plane and needs giant scale power for the electronics.
I was originally using 8800mA 9.9v LiFe packs regulated ( 20A ) down to 5.5v, but then switched to a single 4200mA 9.9v LiFE pack after stress testing.
I typically use 2500mA 6v packs on much smaller planes... e.g. .50's or even down to .40's.
Your additional weight sounds about right given the difference between your engine and the FuJi's much higher weight.
Adding weight should be "useful" weight when possible... and bigger packs give you plenty of flight time, plus the safety factor, while giving you the extra weight you want.