Commercial Fixed Wing
Situational Awareness; Time Pressure
Ground Event / Encounter Other / Unknown
Equipment / Tooling
Super Tug (ST) was assigned to move [an Aircraft X between gates]. We (Driver & Observer) went over to [the] Dockyard to do our User's Check and we were stationed waiting for the plane to arrive. We waited for the crew to download the cargo then I went upstairs to await driver's advice for the brakes to be released. Brake was released and I moved the jet-Bridge off the plane. We started the push- off clearance and arrived at [the next gate]. I got off the ST to do my Walk-a-round when the Driver frantically signaling that there's smoke on the front; right side of the ST. I stopped my walk-a-round immediately and went over to the area where smoke was coming from; when suddenly an 'explosion of fire' broke out from the Radiator through the cover. The Driver came over but I told him to call 'Fire Department' and Supervisor on the radio and tell them 'FIRE; Fire; ST'. I took the nearest Extinguisher Bottle and starting spraying where the fire and smoke was coming from. After a few sprays I opened the Radiator top cover and started spraying into where I could see where the most smoke was coming from. I sprayed for about 5-9 minutes. We stopped for a while thinking that it may have been extinguished; when suddenly another burst of flames came from the left bottom corner where the oil filter look-alike is located. In the meantime [another crew] went to get an extra Extinguisher Bottle from the Tractor and on Standby with it while the Driver was making all the necessary emergency calls. When fire exploded the second time I was more worried that it was still captured to the plane and certainly did not want to see the fire spread on to the Plane's Nose Gear as that would spell disaster for the plane.I kept up the spraying until the Fire was determined to be extinguished but still with visible smoke; then I moved quickly to the ST cabin and started the ST engine up; while [other crew members] were on standby with their Fire Extinguishers.After starting the ST; I waited awhile; to make sure it does not explode on me or anyone; then I 'uncaptured' the CRADLE from the Nose Gear and moved the ST away while [being] guided off [and other crew members] were still on standby with the Extinguishers.Finally when [the plane] was uncaptured; [I was] hurriedly guided off the 2021 while smoke was still pretty much on the heavier side. By this time all the help had arrived from the Safety Team. Finally ST was moved as far away as possible from [the plane] and smoke and fire was contained.
[Report narrative contained no additional information.]
A Super-Tug crew reported that after positioning an aircraft the tug caught on fire.