(Wichita Kansas, USA)
What is the definition of Hobbs time?
ANSWER: I don't think there is a formal definition for Hobbs time, but I can tell you that it is a term used to describe the time recorded on a DC hour meter in aircraft. I can record operating time or flight time.
It is usually activated by a switch on the landing gear of an airplane or the collective stick of a helicopter to record flight time. It can also be operated by oil pressure in the case of recording engine operating hours.
The term came from the manufacturer of the device, Hobbs who are now owned by Honeywell.
You can read more about Hobbs meters by visiting Honeywell's website