Narrative:

Helicopter X checked on my frequency inbound and was instructed to enter right downwind runway 30; pilot read back instruction. I made a few other calls to other airmen in my traffic pattern to sequence; and clear while simultaneously receiving a call from helicopter Y on the ground at the FBO. I did not have a departure strip for helicopter Y and coordinated with ground to give helicopter Y taxi instructions to my runway for intersection departure. I observed helicopter X on right downwind; as instructed passing the midpoint of the runway. During all of this I was also receiving a coordination request verbally from the other local controller beside me regarding inbound instructions to other arrivals outside of the airspace. Later helicopter X reported on right base runway 30 and was promptly instructed to turn back to the downwind and extend. The pilot read back the instruction and I observed helicopter X on a base heading in a left turn back to the downwind. I continued sequencing and clearing other aircraft in the pattern and as I was making one transmission to another airmen I lost sight of helicopter X; on the extended right downwind; behind two controllers in the tower cab conducting a position relief briefing at the operational supervisor in charge desk. I stood up to regain sight of helicopter X flying directly through the final approach course for runway 30; approximately 1 mile final. There was already a C172; approaching 1 mile final cleared for runway 30. Helicopter X appeared disoriented and was flying very fast for the phase of flight they were in (VFR traffic pattern). I sent cessna around and asked helicopter X if they had the airport environment in sight. The pilot responded in the affirmative and I instructed them to turn around and intercept final for runway 30. At that time the pilot reported a near midair collision with the fixed wing (cessna). Helicopter X continued on a south heading through final and now approaching the opposite downwind. I issued a suggested heading to fly to helicopter X to reorient the pilot on the opposite downwind and the pilot read it back. I then issued a sequence number 2 and pointed out traffic on base to final; another cessna; to follow. I observed helicopter X now on an easterly heading approaching final for runway 30; opposite direction again. I asked the pilot his heading; he read back an easterly heading that was 35 degrees off from what I had suggested. At that point I made the decision to make helicopter X #1 to the runway and climb the two cessna's I had originally planned for helicopter X to follow on final above pattern altitude to overfly the runway. I coordinated with ground for the taxi route of helicopter X to legend and issued instructions to helicopter X to taxi to the FBO after landing. I asked helicopter X if he was familiar and the pilot responded in the affirmative.runway 30/12 operations at this airport are already faced with many obstructions to views causing difficulties for controllers. Although the runway is visible; aircraft holding short of the runway are blocked by a building. There is a cctv (closed-circuit television) camera that faces this blind spot but it has been a black screen in the tower cab (OTS) for almost a full year. Radar coverage is very poor southwest of the airport and that is typically where the fixed wing traffic pattern/inbounds are on runway 30/12 ops. On this particular day; the radar was a black screen due to a widespread outage. There are antennas that protrude through the visual scan of the runway from the perspective of the tower cab. The tower cab position configuration puts the controller in charge; FD; clearance delivery; and ground control all in-between the LC1 controller and runway 12/30 creating obstructions to view when controllers stand (position relief; making the ATIS; people walking up the stairs into the tower cab; not enough chairs; etc.)I would recommend that all controllers be aware of the distraction that simply entering the operations area (especially a small VFR tower) and relieving another controller may create; and to act accordingly to minimize the negative impact to the controllers on position.

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Original NASA ASRS Text

Title: Two Tower controllers and a Helicopter pilot describe a near miss at a busy airport where communications and radar were hampered by outages.

Narrative: Helicopter X checked on my frequency inbound and was instructed to enter right downwind runway 30; pilot read back instruction. I made a few other calls to other airmen in my traffic pattern to sequence; and clear while simultaneously receiving a call from Helicopter Y on the ground at the FBO. I did not have a departure strip for helicopter Y and coordinated with ground to give helicopter Y taxi instructions to my runway for intersection departure. I observed Helicopter X on right downwind; as instructed passing the midpoint of the runway. During all of this I was also receiving a coordination request verbally from the other local controller beside me regarding inbound instructions to other arrivals outside of the airspace. Later Helicopter X reported on right base runway 30 and was promptly instructed to turn back to the downwind and extend. The pilot read back the instruction and I observed Helicopter X on a base heading in a left turn back to the downwind. I continued sequencing and clearing other aircraft in the pattern and as I was making one transmission to another airmen I lost sight of Helicopter X; on the extended right downwind; behind two controllers in the tower cab conducting a position relief briefing at the Operational Supervisor in Charge desk. I stood up to regain sight of Helicopter X flying directly through the final approach course for runway 30; approximately 1 mile final. There was already a C172; approaching 1 mile final cleared for runway 30. Helicopter X appeared disoriented and was flying very fast for the phase of flight they were in (VFR traffic pattern). I sent Cessna around and asked Helicopter X if they had the airport environment in sight. The pilot responded in the affirmative and I instructed them to turn around and intercept final for runway 30. At that time the pilot reported a NMAC with the fixed wing (Cessna). Helicopter X continued on a south heading through final and now approaching the opposite downwind. I issued a suggested heading to fly to Helicopter X to reorient the pilot on the opposite downwind and the pilot read it back. I then issued a sequence number 2 and pointed out traffic on base to final; another Cessna; to follow. I observed Helicopter X now on an easterly heading approaching final for runway 30; opposite direction again. I asked the pilot his heading; he read back an easterly heading that was 35 degrees off from what I had suggested. At that point I made the decision to make Helicopter X #1 to the runway and climb the two Cessna's I had originally planned for Helicopter X to follow on final above pattern altitude to overfly the runway. I coordinated with ground for the taxi route of Helicopter X to legend and issued instructions to Helicopter X to taxi to the FBO after landing. I asked Helicopter X if he was familiar and the pilot responded in the affirmative.Runway 30/12 operations at this airport are already faced with many obstructions to views causing difficulties for controllers. Although the runway is visible; aircraft holding short of the runway are blocked by a building. There is a CCTV (Closed-circuit Television) camera that faces this blind spot but it has been a black screen in the tower cab (OTS) for almost a full year. Radar coverage is very poor SW of the airport and that is typically where the fixed wing traffic pattern/inbounds are on runway 30/12 ops. On this particular day; the radar was a black screen due to a widespread outage. There are antennas that protrude through the visual scan of the runway from the perspective of the tower cab. The tower cab position configuration puts the CIC; FD; CD; and GC all in-between the LC1 controller and runway 12/30 creating obstructions to view when controllers stand (position relief; making the ATIS; people walking up the stairs into the tower cab; not enough chairs; etc.)I would recommend that all controllers be aware of the distraction that simply entering the operations area (especially a small VFR tower) and relieving another controller may create; and to act accordingly to minimize the negative impact to the controllers on position.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.