Date: 201503
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Aircraft: EMB ERJ 190/195 ER/LR
Operator: Air Carrier
Operating under: Part 121
Mission: Passenger
Flight phase: Parked
Aircraft component: Escape Slide
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Other / Unknown
Second reporter function: Flight Attendant In Charge; Flight Attendant (On Duty)
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Other / Unknown
Detector: Person Flight Attendant; Person Flight Crew
When detected: Aircraft In Service At Gate
Result: General Flight Cancelled / Delayed; General Maintenance Action
Contributing factors: Aircraft; Human Factors
Primary problem: Ambiguous

Narrative: After our arrival we taxied to the FBO. I parked the airplane and stairs were pulled up to the L1 door. The A flight attendant (FA) disarmed the door and signaled thumbs up to the ramp crew that it was safe to open the door. No one responded; so I opened my cockpit window and asked if the ramp crew wanted us to open the door and the ramp crew said yes. I told the A flight attendant that it was ok for her to open the door from the inside. The door indication in the cockpit was showing red at that time. Upon opening the L1 main cabin door the Flight Attendant felt resistance so she stopped pushing on the door and brought the door toward her. She immediately brought this to my attention and told me that she disarmed the door before opening but she saw something sticking out of the bottom of the door. I then went outside of the cockpit to inspect the door. I saw the door handle was up with a green disarm indication; both red handles in the up position and a red girt bar indication. I immediately realized that something was wrong and told the flight attendants not to open the door. I contacted Maintenance Control and told them about the situation. The maintenance controller said that they would have to look up what the indications should be and that we should probably check the other door to see. During the time when I was on the phone with Maintenance Control and trying to verify the correct door indications; the B flight attendant managed to reclose the L1 door without my permission and claimed that this would reset the mechanism. After checking the rear door indications I called Maintenance Control and was advised that contract mx was on their way and that I should attempt to open the door. I then asked if the slide would deploy. Maintenance Control replied that it may or may not; and that the door would have to be opened either by the crew or contract maintenance in order to verify its operation. I agreed to open the L1 door under direction from Maintenance Control and advised the FBO of our attempt to open the door; so that they would clear the area of all equipment. I was reassured by the Maintenance controller that Maintenance Control is taking responsibility in case of slide deployment. I then proceeded to open the door with the slide being deployed. During slide deployment the door assist mechanism did not activate. After this event I asked the A flight attendant if she verified all the door indications; including the girt bar. She replied that she did but wasn't sure about the girt bar indication since it was dark in the cabin and she wasn't completely sure if it was clear and not red. I then contacted Maintenance Control again; made the required log book entry and after the slide was detached from the aircraft; we ferried the airplane.


Second narrative: As A-FA I went to the door to wait for the jet bridge to come. There was a person outside rather than the jet bridge. I disarmed my door. I gave the thumbs up and he looked back at me. I then asked the captain about opening up the door and he gave me permission to do so. I opened up the main handle and immediately felt a resistance as I attempted to push the door back. There were also two pins showing and I knew then something wasn't right. I then told the captain I didn't feel comfortable opening the door and he got on the phone with maintenance. Maintenance advised him and I that we will still need to open the door in order for the problem to be resolved. I was told to open up the 1R door to ensure I seen the same thing. I advised there were no pins showing. The captain then proceeded to open up the 1L door and the maintenance person ensured he would take responsibility for advising us to open the door. The slide inflated. I feel that I did what was necessary to disarm and open the main cabin door. These are procedures in which I've been trained to do. And I'm confident that I did it correctly.


Synopsis: An EMB190 flight crew and the Flight Attendant involved; describe the circumstances surrounding an unintentional slide deployment.