EMB ERJ 145 ER/LR
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Other / Unknown; Situational Awareness; Time Pressure; Workload
Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Flight Crew Returned To Gate; Flight Crew Took Evasive Action; General Flight Cancelled / Delayed
Aircraft
During pushback off of [gate] in ZZZ; the I noticed white smoke and a burning odor. The smoked seemed to be coming out from under the First Officer avionics panels. We stopped the pushback and shut off the engine we had just started. Initially; based on the rapid rate at which smoke was filling the cockpit; I decided to make an announcement to evacuate using the main boarding door without stairs. There were only 14 passengers on board and we had several ground crew outside to help with deplaning without steps. However; the smoke seemed to subside rather quickly when we opened the cockpit windows so; as a crew; we decided that we now had time to have the tow pull us back into the jet bridge to make a safer; more normal deplaning situation. I made another announcement explaining the situation and for each pax to take the nearest seat. We then pulled back into the jet bridge and deplaned. We then shut down the aircraft completely. We returned the personal belonging to the passengers and eventually swapped to a spare aircraft and continued to ZZZ1.We handled the situation in the cockpit by shutting down the engine; opening windows and running the QRH procedures. The procedures are obviously made for inflight; but it had us turn off recirc and gasper fans. We then shut off all inessential electronics and avionics once we talked to everyone we needed to. Since the smoke subsided; we felt like we had time to pull up to the jet bridge and deplane rather than risking a evacuation without stairs. I had called Dispatch right after we deplaned. I was bombarded with many people such as gate managers; ramp managers; [Crash Fire Rescue]; etc. as I was on the phone. Next time I'll wait to call Dispatch and Maintenance until all the information is relayed to the different people on the ground.
EMB-145LR Captain reported smoke in the cockpit during pushback that resulted in a return to the gate.