Regional Jet 700 ER/LR (CRJ700)
Aircraft Equipment Problem Less Severe; Inflight Event / Encounter Weather / Turbulence
General None Reported / Taken
Weather; Aircraft
On the ride to the hotel a captain who had been riding in the back of the aircraft showed me a picture of our right wing during the approach. The picture of the wing showed ice building on top of the wing behind the heated leading edge. The picture seems to show a significant amount of ice.  I have never previously encountered this.Prior to entering the clouds we had already turned on the anti ice and had green wing and cowl indication.  The bleed air had already been transferred to the APU to maximize air available for the anti ice system.  The picture of the ice is of the right wing. The left wing ice detection light didn't shine on the wing; so I couldn't see any ice on my side. The First Officer was flying so not looking back at his wing much.  We picked up moderate mixed ice on the descent and we did report it to approach.  After I arrived at the hotel I contacted dispatch and maintenance control to report what I had learned. I wanted to make sure other pilots were warned if coming in and I also wanted to have the ac checked for proper operation of the anti ice system as I didn't think there should be roll back like that on a hot wing.    Suggestions:  Inquire with Bombardier to see if this was an expected situation.
A CRJ-200 Captain was advised by a passenger on his aircraft that significant ice had built up on his right wing.  He learned of this after the flight and wondered whether the manufacturer would consider this to be an expected situation.