Confirm that, definitely an air hose. Our guys had to use a series of air bags to lift a KingAir that came in without its gear (known ahead of time thankfully) and pump them down so we could tow it off.
ARFF (Aircraft Rescue Fire Fighting) trucks do have handlines if they're necessary, but their primary purpose is to deliver AFFF (Aqueous Film Forming Foam) through turrets mounted on the bumper or roof of the truck. Usually the handlines are for delivering sodium or potassium based dry chemical into sensitive electronic areas of the aircraft--that wouldn't do very well with a couple hundred gallons of water-mixed foam shooting into them.
Sucks that this happened, but I have to admit...looks like he did a great job of getting it on the ground safely after what happened
-Brandon