If I understand your post, you've tried different receivers and different batteries and different servos in this plane? And your transmitter works fine with other planes? If that's right, about the only thing left is any extensions you have in this plane. For the sake of thoroughness, I'd cycle the battery to be sure it's a good battery, then check the amps that your servos are pulling with a multimeter. It's simple enough to wire up a harness to do that with. Then try eliminating extensions to see if it works when you take one away.
It's also helpful just as a general setup tool to make a servo plug lead for your meter so you can monitor receiver voltage while you move the sticks. In your case, that will tell you what's really happening in your system. If you still show 5+ volts when the receiver goes black, then you can eliminate a bad battery or servos drawing too many amps.