I have a T 28 Trojan and on my forth flight it went into a dive twice and I had no control. I was able to recover before it hit the ground. It was as though I had lost the bind to the aircraft. I am using a Spectrum DX5e transmitter and AR500 receiver. I was also using the battery from my Mustang BL, if that matters. I have been flying my Mustang for two months with the same radio setup and never had this problem. Any ideas why this would occur?

Get rid of the Spektrum. That's what I did. Too many posts of losing bind and people crashing planes. I changed brands.

Lancer:

It might help to have a bit more info about your aircraft... size, servos, flight length, battery (V, maH), etc.

My initial guess would be that if it's a 4.8V battery pack of relatively small size (600/700 mah), after 3 or 4 flights you might be flirting with the pack delivering less than 3 volts, especially if you're turning the aircraft sharply and putting a load on two or three of the servos. That would cause the infamous Spektrum blackout, which you might recover from if the servos go back to neutral during the dive and the pack voltage goes back up to 3.5/4V.

I think he is talking about the Parkzone t-28, which is electric and Lipo powered. Most likely you do have a problem with rx, but check the servo mounting to be sure. I've had a couple of elevator servo's work loose on these planes. Some gorilla glue, Foam safe CA, or some UHU would be a cheap fix or cheap insurance.

Ditto as Hugger stated, also if it is the PZ version check to see which esc it has. Some came with a 20 or 25 amp version and they were notorious for having the bec overload and die.
Would send your rx into a reset/rebind if the volts dropped. Which in turn means no control.

What most of us did was install a stand alone bec to correct this.
Horizon has since upgraded the esc in them.

I have a lot of flying on the PZ T-28 with a Spektrum DX-6i and AR6110 reciever. My first airplane and I learned to fly on it. Still with me after almost a year and going strong. I've swapped the ESC to a 45 amp unit and replaced the elevator and one aileron servos. Eventually the covering on the horizontal stab will come loose and can cause some control problems when it happens inflight. Get some strong tape and cover the leading edges of the stab to prevent the air getting underneith and peeling it back over the elevator. When it happened to me, I lost all down elevator control. The radio has been trouble free all this time.