Date: 202001
Local time of day: 0001-0600
Location: OGG.Tower, HI
Aircraft: Cessna 150
Operating under: Part 121
Flight plan: VFR
Flight phase: Final Approach
Airspace: Class C OGG
ATC / advisory: Tower OGG
Second aircraft: B737 Undifferentiated or Other Model
Aircraft component: Engine
Component problem: Malfunctioning
Reporter organization: Government
Reporter function: Local
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Time Pressure; Situational Awareness; Troubleshooting
Anomaly: Aircraft Equipment Problem Critical
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Flight Crew Landed in Emergency Condition
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: I was working Local Control when Aircraft X departed to the Southeast. The coordination on the VFR strip stated he was going to be headed to Kihei for fish spotting. Once he was in his right turn SE bound; I switched him to departure. As he approached the outer boundary of Kahului's Class C airspace; his squawk code changed to 1200. Meanwhile; Aircraft Y was on the RNAV Z approach to Runway 2; and was east of the airport on the right downwind. The 1200 code; which was Aircraft X; started to circle back towards the airport and appeared to be making a 5 mile straight in for Runway 2 as Aircraft Y was on a 5 mile right base. I picked up the binoculars and spotted Aircraft X pointed at the airport. I then noticed that Aircraft Y was high at about 3;600 feet. While this was taking place; the Cab Coordinator (CC) was on the line with approach discussing Aircraft X's priority status. Aircraft Y was being sent around. Aircraft X checked in on my frequency on about a 4 mile final. I cleared him to land Runway 2 and issued the winds at the approach end. He said he was unsure if he would be able to make it to the airport. I asked for the nature of his situation. He said his engine was in rough shape and it was not looking good. I advised him that rescue vehicles would be standing by. The Supervisor on duty worked to get a hold of crash fire rescue on ground frequency as well as the crash phone. Aircraft X's transmissions were coming in partially broken and it was tough to understand at times what he needed and what exactly the problem was. I issued a cautionary wake turbulence advisory for the Aircraft Y aircraft that had passed above him. Aircraft X landed safely on Runway 2 and exited at F to parking. He was met by rescue vehicles on the East Ramp. A follow up Runway inspection was performed by operations to make sure the Runway was clear of debris and ready for use. No separation was lost and all aircrafts made it to their destinations safely.During an emergency; it is important that everyone in the tower cab be made aware of the emergency and which aircraft is experiencing it. Although the cab coordinator and myself were aware of the emergency; and the OS and Ground Controller became aware of it from overhearing our conversation; it would have been more beneficial for both the CC and I to announce to the rest of the cab; that Aircraft X was inbound as an emergency. That way we acquire extra human resources who can help us safely handle the dire situation with many moving parts. I do not believe there was anything I could do to prevent the emergency; but I do believe that my coordination with my team members could have been better. I also think I could have slowed down the operations at the airport. While Aircraft X was inbound with the emergency; I was still departing aircraft. This forces the extra workload on my CC as well as the coordinating sectors who will be affected by having to work the departures. Although no aircraft were put at risk; it may be wiser in the future to minimize my amount of work and put my full focus into providing the best service I possibly can; to any emergency aircraft.




Synopsis: OGG Tower Controller reported a VFR aircraft had to return due to a engine that was rough running which caused an aircraft to be resequenced.