This morning at work we got to talking about how much weight is on the nose gear of an airplane. It came up because I had watched a video of a B-1B landing on Rogers Dry Lake because the nose gear didn't extend. Someone made a joking comment about having a pickup drive along and catch the nose. So I made an offhand comment that the truck would need to be able to go 150 mph and be able to hold 100,000 pounds. Which for the B-1 is a pretty big overestimate, but for something like a 747 or similar is probably pretty close to the ballpark.
This got me remembering the first time I saw a tow-bar-less pushback tug. My first thought was that it was a brilliant idea since you didn't have to screw around with hooking and unhooking tow bars, and it would make changing directions much easier. My second thought was "wow, that thing needs to lift some serious weight". I was so impressed that I had to take a picture of it. That's right, I'm the guy taking pictures of industrial equipment when I'm on vacation.
Looking at this picture I was able to get enough information to do some Googling. Turns out that I photographed a GHH Fahrzuege AM500. This particular pushback tug has a lift capacity of 50t metric, or about 110,000 pounds. It has a deadweight of 33,200 kg (~73,000 lbs) and is powered by a 440 kW (590 hp) Deutz TCD 2015 V08. These feature hydrostatic four wheel drive, most likely to deal with the fact that you can't put an axle between the rear wheels. It is capable of moving widebody airliners up to the A380, though if you need to move an A380 you need to spring for the XL version which has more power and is slightly wider and heavier. Interestingly enough the XL has the same 50t capacity as the standard AM500.
The AM500 has some interesting features to make life on the tarmac a little easier. The cab can be lifted slightly to improve visibility when hooking up an airplane. The dash seat and pedals are all mounted on a turntable that allows the operator to face in either direction while operating the tug. The controls are conveniently tied in to the turntable so that they automatically match the direction the operator is facing.
Here is a video showing how this type of tug lifts the nose gear:
And here is a longer tug drivers view of a 747 pushback:
And here is a 10 minute long video of a KLM ground crew members last day at Amsterdam Schipol. It comes complete with rousing theme music soundtrack. DISCLAIMER: I watched the first minute and decided to post it here based on soundtrack alone.
The first picture is mine, the second from the AM500 website.