Type, grade, class?

Question

In army helicopter technical manual, mil specifications have type, grade, class. I known class. Class is flammable liquids.

What is type?, What is grade?

I cannot find definition of type, grade and class in web site.

Where are definition of type, grad, class?

Or Mil spec?

I want to definition of type, grade, class.

Answer 1

type i think is the base or origin like vegetable or from animals or synthetic grade is the amount of concentration. Check out the grease manufacturer or the Mil Specs, the label will tell it all.

Answer 2

As you may know most if not all MIL-Specifications are being changed over to ASTM standards same thing different name and now they cost to purchase them.

For every grease, fuel, hydraulic oil is an ASTM standard.  Where the word grade comes from is the manufacturer specification data sheet.  The specification will reference a grade to be used or ASTM standard or MIL-Specification.

Oil grade or specification is the same thing as an example grades of Aviation Gasoline for Grade 80/87.

Civil aircraft means aircraft other than public aircraft.

Class:

(1) As used with respect to the certification, ratings, privileges, and limitations of airmen, means a classification of aircraft within a category having similar operating characteristics. Examples include: single engine; multiengine; land; water; gyroplane; helicopter; airship; and free balloon; and

(2) As used with respect to the certification of aircraft, means a broad grouping of aircraft having similar characteristics of propulsion, flight, or landing. Examples include: airplane; rotorcraft; glider; balloon; landplane; and seaplane.

Type:

(1) As used with respect to the certification, ratings, privileges, and limitations of airmen, means a specific make and basic model of aircraft, including modifications thereto that do not change its handling or flight characteristics. Examples include: DC–7, 1049, and F–27; and

(2) As used with respect to the certification of aircraft, means those aircraft which are similar in design. Examples include: DC–7 and DC–7C; 1049G and 1049H; and F–27 and F–27F.

(3) As used with respect to the certification of aircraft engines means those engines which are similar in design. For example, JT8D and JT8D–7 are engines of the same type, and JT9D–3A and JT9D–7 are engines of the same type.