A300
Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Aircraft Equipment Problem Less Severe
Flight Crew Executed Go Around / Missed Approach; Flight Crew Overcame Equipment Problem; Flight Crew Requested ATC Assistance / Clarification; General Maintenance Action
Aircraft
We were cleared for ILS. I called for the gear down [and] landing checklist. We both noticed the left main gear unsafe indication on the forward panel and on the overhead gear indicator panel. (Red Unlk and Amber Door.) I had First Officer cycle gear with same result. We notified ATC that we needed to discontinue approach because of unsafe gear. We were given straight ahead to 3400 feet then followed by a turn to 270 and climb to 5000 feet. After cleaning up jet and after takeoff checklist complete. I told ATC to vector us for another approach while we worked checklists.  We attempted another gear extension with unsafe indication. I called for the L/G Unsafe Indication QRH checklist directed by ECAM. We followed QRH PROC. With the unsafe indication on both panels we followed the QRH PROC. L/G Gravity Extension and got three down and locked with gear doors open. We let ATC know that we had no nose wheel steering and could we roll to the end so company could tow us in. We let ATC know we were secure. Mechanic pulled up and we had him pin all landing gear. We sent ACARS to [Operations Control] to inform them of situation. I made [a maintenance log] entry and briefed the mechanic of event. Mechanical failure of gear doors or landing gear mechanism.
A300 Captain reported extending the landing gear through the alternate method after it failed to extend normally.