Quoted from "The Air Pilot's Manual, Volume 4"
"Normal Category- below 5,700kg and non- acrobatic: manoeuvres limited to stalls and steep turns of 60deg. Typical limit load factors +2.5g and -1.0g
Utility Category- as for Normal category, plus limited aerobatics. Typical limit load factors are +4.5g and -1.8g
Acrobatic Category- fully aerobatic. Typical limit load factors are +6.0g and -3.0g"
The Utility Category line on the CoG graph shows where the aeroplane CoG is within the utility category. So if your do your maths and the dot on the graph is within the line, the aeroplane falls into the utility category and vice versa.
Hope this helps. Correct me if I'm wrong you knowledgable chaps.
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