| 1 | HLK | Heli-link Helikopter AG | Callsign: Heli-Link, Name changed to DC Aviation Switzerland AG. | CH | AVCODES |
| 2 | HLK | DC Aviation Switzerland AG | Callsign: Heli-Link, ICAO designator changed to DCH. Name changed from Heli-link Helikopter AG. | CH | AVCODES |
| 3 | HLK | Heli-Link | | | ICAO1 |
| 4 | HLKA | HELKA EXPRESS INTERNATIONAL LTD | | | SCAC4 |
| 5 | HLKC | H & L TRUCKING LLC | | | SCAC4 |
| 6 | HLKD | HILKER, DENNIS R TRUCKING INC | | | SCAC4 |
| 7 | HLKE | HLINKA ENTERPRISE INC | | | SCAC4 |
| 8 | HLKG | HEATLINK GROUP INC | | | SCAC4 |
| 9 | HLKJ | HILL TRUCKING INC | | | SCAC4 |
| 10 | HLKN | HALLS TRUCKING | | | SCAC4 |
| 11 | HLKQ | HALEAKALA TRANSPORTATION & WAREHOUS | | | SCAC4 |
| 12 | HLKS | HALL, KEITH & SONS TRANSPORT LTD | | | SCAC4 |
