Most web sites say 1900 ft/min, others range from 1700 to 2100 (Lockheed uses the 2100 number)ft/min.
Time to 6100 m - 12 minutes.
Data here: http://www.lmaeronautics.com/products/airmobility/c-130/specs.html
That's in an international standard atmosphere: sea level, 59 degrees F. The altitude and temperature in Baghdad seriously degrade the performance of aircraft. The temperature has the effect of lowering the density of the air, and making the effective altitude (airmen call it density altitude) higher.
It reduces the lift of the wings (fewer air molecules to hold the machine up) and it reduces the power of the motors, although with turbine motors that's not very serious because they are designed for max efficiency at high altitudes to begin with. But hot weather is not the pilot's pal.
The plane was an RAAF Hercules. American made, but owned and operated by the Australians, who have been great allies.
That report makes it evident that the Ali Babas are in fact, an organised, stay behind element. That is actually good because where there are tendrils of organisation there are traces that intelligence operatives can follow. It will take time and patience, but these men are doomed.
Note that the hostage takers are asking for freedom for their buddies. That is why counter terrorism courses used to teach, under no circumstances take a terrorist alive. Unfortunately we have too many lawyers and not enough people with CT training making the calls in Baghdad. I doubt the nascent Iraqi government will be so prone to observe the niceties.
d.o.l.
Criminal Number 18F