Air brakes have absolutely ZERO determination in whether or not a vehicle requires a CDL.
Only if it's a vehicle equipped with air brakes.
No. Air brakes are not a parameter in determining whether or not a vehicle needs a CDL.
Air brakes are entirely irrelevant as far as whether or not that vehicle needs a CDL is concerned. The only time you need a CDL to drive an RV is when you're operating it on a for-hire basis, either as a driver for hire or as a transporter.
brakes.
The air brakes don't matter, insofar as whether or not a CDL is required. As for the GVW being over 26,000 lbs., yes, unless your vehicle falls in criteria for the farm vehicle, military vehicle, emergency vehicle, or recreational vehicle exemptions.
Only if it's a: transporting hazardous materials or b: a bus designed to transport more than 15 persons (including the driver).
Only if it's hauling hazmat or is a bus designed to transport more than 15 passengers (including the driver). Air brakes have absolutely nothing to do with whether or not a vehicle requires a CDL.
If it's not a firefighting or first response vehicle, recreational vehicle, registered farm vehicle, or military vehicle (operated by military personnel in the course of their duties), then yes - not because of the the air brakes, but because of the weight rating of more than 26,000 lbs. GVWR.
To answer you we need to know what country's traffic regulations you are asking about.
Only if it's transporting 16 or more persons (including the driver) or sufficient quantities of hazardous material to require placarding with HAZMAT warning signs.
No, unless you're hauling something which requires a hazmat endorsement, such as contaminated soil.
Air brakes have zero determination as to whether or not a vehicle requires a CDL. The only time you need a CDL for a vehicle under 26k is when it's a bus designed to transport more than 15 persons (including the driver) or a vehicle hauling a quantity of hazardous materials which requires the display of placards.