| 1 | SCK | Sky Cam | Callsign: Skycam, | F | AVCODES |
| 2 | SCK | Sky Cam | | | ICAO1 |
| 3 | SCK | South Central Arkansas Ry., Inc. | added 7/1982; eliminated 1/1984 | | NAKINA |
| 4 | SCK | South Central Arkansas Ry., Inc. | added 7/82 | | NRHS |
| 5 | SCK | SOUTH CENTRAL ARKANSAS RAILWAY | | | PWRC |
| 6 | SCKA | SILVER CREEK BISON RANCH | | | SCAC4 |
| 7 | SCKF | SUNNY CREEK FARM | | | SCAC4 |
| 8 | SCKH | STREAMLINE TRUCKING | | | SCAC4 |
| 9 | SCKK | SANTELLI TRUCKING INC | | | SCAC4 |
| 10 | SCKL | STURGEON CREEK WELDING | | | SCAC4 |
| 11 | SCKL | Schröder & Klaus GmbH + Co. KG | | DE | VKM |
| 12 | SCKM | SCHRECKE | | | SCAC4 |
| 13 | SCKO | SCHENKEROCEAN | | | SCAC4 |
| 14 | SCKP | SCHUCKS ASPHALT PAVING LLC | | | SCAC4 |
| 15 | SCKQ | SCHILL TRUCKING INC | | | SCAC4 |
| 16 | SCKR | STALLION ROCKIES LTD | | | SCAC4 |
| 17 | SCKT | STAMPEDE CREEK TRANSPORTATION LTD | | | SCAC4 |
| 18 | SCKU | SCK-CEN | | B | BIC |
| 19 | SCKV | SELWAY CORPORATION | | | SCAC4 |
| 20 | SCKX | The Short Creek Coal Co. | 8/1920 | | NAKINA |
| 21 | SCKX | Standard Chlorine Chemical Co. | 1/1943-1/1946 | | NAKINA |
| 22 | SCKX | Spring Creek Coal Co. | added 10/1985; eliminated 10/1986 | | NAKINA |
| 23 | SCKX | Northern Coal Transportation Co. | added 10/1986; 1/1994-7/2005 | | NAKINA |
| 24 | SCKX | Spring Creek Coal Co. | eliminated 10/86 | | NRHS |
| 25 | SCKX | Northern Coal Transportation Co. | added 10/86; 1/94-7/2000 | | NRHS |
| 26 | SCKX | *SHORT CREEK COAL CO. | | | PWRC |
| 27 | SCKX | *STANDARD CHLORINE CHEMICAL CO. | | | PWRC |
| 28 | SCKX | +NORTHERN COAL TRANSPORTATION CO. [SPRING CREEK COAL CO.] | | | PWRC |
| 29 | SCKX | Northern Coal Transportation | | | RSRV |
| 30 | SCKX | NORTHERN COAL TRANSPORTATION CO. | | | SCAC4 |
| 31 | SCKY | SAPPHIRE COURIER SERVICE INC | | | SCAC4 |
