Regional Jet 900 (CRJ900)
Flight Crew Air Transport Pilot (ATP)
Distraction; Confusion; Situational Awareness
ATC Issue All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Procedure; Airspace Structure; Human Factors
Were given new full route clearance on the ground and told to expect 8;000 feet as final. We asked for clarification and they said it was because of congestion in New York airspace. So we assumed it was just 8;000 to get us out of the New York area. After takeoff we were told to maintain 8;000; then about 30 minutes later told to descend to 6;000 for traffic. This was the highest altitude we could get for the remainder of the flight. We went from New York area to Georgia at 6;000 feet. We notified dispatch before we left and during flight a few times.We were handed off to multiple TRACONs along the route and some of them were unfamiliar with our call sign. One I think we missed a couple calls because he was calling us something else and we didn't catch it. Over one intersection we got a traffic call from ATC; a C172 I believe. Was passing off our right opposite direction. We had visual contact the entire time; but as he passed us we got a TCAS TA followed by any RA of 'monitor vertical speed.' He passed above and to the right of us +300 feet according to the TCAS. We reported the RA to ATC and he basically just said sorry. Later on we had a second TCAS RA same type with another GA aircraft. ATC never pointed that one out; but we had visual contact the entire time. The remainder of the flight was uneventful with the exception we were about 30 plus minutes late getting in due to the 250 knot restriction. Fuel wasn't an issue; we kept close track of it and landed with extra.I still don't know why we got this altitude. There were a couple of other 121 regionals at the same altitude as us in that direction. It would have been safer for ATC just to delay us getting out and give us a higher altitude than having us down at the same altitudes as GA operators for that long of a distance.
CRJ-900 pilot reported of a final altitude of 8;000 feet for the flight from the New York area to Georgia.