CASA has specified three airworthiness standards for civil aircraft; these three standards are Normal, Utility and Aerobatic. The difference between these three category aircraft is basically the limit load factors or the amount of G loading the aircraft can withstand.


Normal category – Normal category have to be able to withstand +3.8 Gs to - 1.52 Gs.


Utility category – Utility category have to be able to withstand +4.4 Gs to - 1.76 Gs. And both Utility and Normal category’s have to be able to withstand - 0.4 times there positive G limit.


Aerobatic category – Aerobatic category aircraft must be able to stand +6.0 Gs to – 3 Gs or 0.5 times the positive limit in negative Gs. They to have a maximum number of seats excluding the pilots of nine or less and no passenger in a seat should weight equal or over 86Kg except that seats may be placarded for a lesser weight. And the aircraft must have a maximum take off weight of 5700kg or less. Aerobatic aircraft must be robust and aircraft certificated in the acrobatic category are designed to be significantly stronger than utility or normal category planes. An aircraft certified for aerobatics doesn’t mean that it can perform all manoeuvres usually; the manoeuvre limitations are shown in the aircraft’s flight manual. This is because an aircraft can usually withstand higher G limits than it is certified for but will break if done so.


Pilots must be cautious that many aircraft were designed to standards that existed before and soon after World War II, and some aircraft used in casual aerobatics were designed to various military and other standards. The pilots must also take into account the effects of time, such as corrosion, material quality, build quality, metal fatigue and others that affect the aircraft’s structural integrity. Because of this manoeuvres that were safe in the past may not be safe now.


CASR doesn’t specify structural standards for amateur-built aircraft, which are mainly used for sport aerobatics, competition, and air display work. Flying aerobatics in amateur built aircraft should only be conducted in aeroplanes with service records of aerobatics or which have been designed and built for that purpose. 




Hosted by