B737 Undifferentiated or Other Model
Air Traffic Control Fully Certified
Communication Breakdown; Situational Awareness
ATC Issue All Types; Conflict Airborne Conflict
Air Traffic Control Issued New Clearance; Flight Crew Executed Go Around / Missed Approach
Weather; Human Factors; Procedure
I was providing OJT to a CPC-IT on Local Control East. The developmental joined me during moderate traffic after I'd worked around 20 minutes. A B737 was set up to land on Runway 35 in front of an E190 (on 27R); however; there was a headwind that affected the 35 arrivals more than the 27R arrivals. We had had several aircraft which were well behind the ghost target (Converging Runway Display Aid-CRDA) for 35; and the 'back end' of the gap was the problem - i.e.; rather than the 35 arrival conflicting with the 27R they were to go behind; they in fact were placed such that once they'd slowed; they conflicted with the 27R arrival following them. It was clear that this would be the problem with the B737; so upon communication with the E190; we asked him to start slowing to his final approach speed; and later asked for an S-Turn for additional room. The two aircraft were still a tie; and at about a 3 mile final on the B737; I asked the CPC-IT how it looked; he responded that it was still a tie; and initiated a go-around with the B737. However; the response was 'Embraer; going around.' I immediately took the frequency and corrected it; telling the E190 that was not for him; however; as I was talking; I saw that E190's nose was already up and that he'd started the go-around. I then reversed the situation and told the B737 he was still cleared to land and fortunately he did continue and land. While I had the frequency; a second tie at the intersection occurred and I sent another aircraft - [a Runway] 35 arrival - around. I fault myself for not taking the time to brief with this trainee about my expectations while training on Local East before actually starting training there. I should've taken the time to talk to him about this situation - there is no 7110.65 phraseology for this tie; but I have used language to tell both aircraft well in advance that it would be a tight one; and which one of them would be going around in the event it did not work. As it worked out; I gave this developmental too much leeway; and nearly had a double go-around occur (tie at the intersection turns into a tie in the air).
PHL Controller providing OJT during simultaneous landing on Runway 35 and 27R and utilizing CRDA described a go around event when the developmental issued the instructions to the wrong aircraft; the reporter noting too much leeway was given to the developmental.