For switching applications, you should simply forget about hFE.
Look, it's not that cut an dried. They are only showing two lines, I
C/I
B = 10 and 50. There a an infinite number of possible lines you could draw in there, and they behave in a fully predictable manner. Just because they only show 2 lines does not mean that other lines do not exist. Or that if you wander off the space between those two lines by a tiny bit, the transistor will behave in a hugely different fashion. A line for a ratio of 55 would be just a tiny bit higher than the line showing the ratio of 50.
My calculations are right. The transistor, will be in saturation, V
CE will be approximately 0.055V with I
C @ 1amp, and it will be at less than 10 degrees above ambient temperature.
You are obviously set on this, so I will not try to convince you further. This argument is just starting to get inane. If you want to prove me wrong, get a ZTX851, drive the base from 5V through a 240 ohm resistor, allow 1 amp I
C (5V through 5 ohms, perhaps) and take some measurements. If it blows up, or even get's luke-warm, I'll play for the transistor and send you $5 for your trouble. Okay?
Other than that, let's agree to disagree.