Dash 8-100
Flight Crew Air Transport Pilot (ATP)
Ground Event / Encounter FOD; Ground Event / Encounter Object
Air Traffic Control Provided Assistance; Flight Crew Returned To Gate; General Flight Cancelled / Delayed
Airport; Equipment / Tooling; Human Factors
Facing south on taxiway Echo with parking brake set. Approximately 1;000 ft behind a 757 which only had the #1 engine running holding short of 27R on Echo. 757 was told to 'expedite' or possibly 'cross without delay' (something to that affect) across 27R as there was an aircraft on short final. The 757 spooled up to comply and his jet blast sent barriers lining taxiway Echo flying. The barriers have been there for the construction going on. They didn't appear to be filled with water or grounded in any way as they were thrown about seemingly with ease. The FO and myself witnessed them start to move along the left side of the taxiway along with a lot of dust and debris. Within seconds a half dozen or so of them were airborne and as they came toward the left wing of our aircraft I brought both condition levers to feather while immediately pulling the number 1 to fuel off. One barrier passed beneath the #1 prop at the same time I was pulling it to fuel off. The prop was still spinning when the barrier passed. I was unsure whether the barrier had hit the prop. With the number one engine secured; I relayed what had happened to ground control on 121.9 and asked for a few minutes. I asked the FO to call the FA to have her look for noticeable damage/hydraulic leaks and to determine whether the barrier had continued past our gear. (I didn't want to run over it if it was close.) I didn't think it had come in contact with the prop; and the FA said the passengers saw it pass beneath the prop so I determined it was safe to single-engine taxi back to the gate on the #2 engine.We accomplished the after landing checklist; contacted ops for a gate and to notify our company; then called ground/ramp for a way to get there. While waiting for clearance to get to our gate I made a PA to the passengers to inform them of our return and gave a brief explanation of why. Returned to the gate without further incident via taxiways Kilo and Foxtrot. Once parked; we deplaned and I contacted dispatch and maintenance. Maintenance didn't detect any contact. We were all in agreement. 'Ok for service.'It was originally a XA05 departure. We closed the gate the second time at XB30 (85 min delay). Arrived at our destination at XC37 which was 83 mins late. Aside from those contacted above; I also spoke with a number ground gave me and gave them a short account of the events. They said they would contact the city for me. I also contacted a number dispatch gave me for the tele-manager in ZZZ. He had stepped out but the woman who answered took a short account of the events as well.
Dash 8 Captain reported jet blast from a taxiing 757 blew construction materials and barriers across the taxiway and into their aircraft. The left engine was shut down to avoid damage to propellers. Aircraft returned to the gate.