Registration Numbers Explained

Registration Numbers Explained.

(Extract from June 1999 Magazine - Page 14. There has been an amendment to CAO 95.25 types)

A few members have queried the registration numbers associated with the classifications introduced by the new CAO 95.55.

Essentially, the issue of CAO 95.55 which became effective on 1 October 1998 introduced two new classes of aircraft:

The Amateur Built Utralight (para 1.5). The AUF registration prefix designated for the Amateur Built series is 19. Amateur built means that the major portion of the aircraft is built by a person for educational and recreational purposes (eg not for sale!).

The Factory Built Ultralight (para 1.6). The AUF registration prefix designated for the Factory Built series is 24. Factory Built means an aircraft that meets a CASA approved design standard and built in a Factory approved to CASA manufacturing standards.

In effect, the 19 is really a heavy 95.10 or 10-xxxx registered aeroplane and the 24 is a heavy 95.25/101.55 or 25-xxxx/55-xxxx. The old numbers will remain because the orders relating to them remain.

The 19 and 24 figures were nominated by CASA in a letter to the AUF. 24 was for Primary Category Aeroplanes and another number, 26 was nominated for Intermediate Category. Both Primary and Intermediate Category aeroplanes are certificated and factory built types but their minimum stall speeds and MTOWs can be well above the AUF aeroplane limits of 45kt stall speed and 544 kg MTOW. However there are some of these aircraft whose specifications will fall 45kt/544kg limits and these will be eligible as ultralights for AUF registration.

Because they are both factory built and must comply with the same limits to be eligible as Ultralights the extra number of 26 is really unnecessary for AUF purposes at this stage, so all factory built aircraft other than CAO 101.55 and 95.25 aircraft will be allocated a 24 prefix. In other words, when you see a 24 on an aircraft, you know it is factory built and certificated – like a 55 or 25.

Aircraft built under CAO 101.28 ie those approved by CASA and amateur built under the supervision of the SAAA remain in the 28 series, but their allowable weight in the AUF has been increased to 544 Kg (1200 lb) with a stall speed restriction in the landing configuration restricted to 45 Kt (52 mph).

Note that the weight limits for floatplanes are higher: 579 kg (1276 lb) for single seat aircraft and 614 kg (1354 lb)for 2 seats while the stall speed requirement is the same at 45 Kt (52 mph).

The Numbers. In summary (and I hope I’m not teaching too many people out there to suck eggs – this is the result of a number of queries):

10-XXXX

These are CAO 95.10 aeroplanes: amateur built with MTOW not exceeding 300 Kg (662 lb) and a wing loading not exceeding 30 Kg per Square Meter (6.14 lb per square ft). Private operations only.

19-XXXX

These aeroplanes are amateur built with MTOW not exceeding 544 kg (1200 lb) and stall speed in the landing configuration not exceeding 45 Kt (52 mph). Private operations only.

24-XXXX

These aeroplanes are CAO 95.55 para 1.6 factory built aeroplanes conforming to a CASA approved certification standard with MTOW not exceeding 544 kg (1200 lb) and stall speed in the landing configuration not exceeding 45 Kt (52 mph). Can be used for training.

25-XXXX

These aeroplanes are CAO 95.25 aeroplanes (CAO 95.25 now having been cancelled). They were to a CASA certificated design and factory built. Stall speeds were not to exceed 40 kt in the cruise configuration and 35 kt in the landing configuration with an MTOW not to exceed 400 kg (882 lb) for early aircraft and 450Kg (992 lb) for later aircraft approved for that weight . Can be used for training. CAO 95.25 was cancelled on 28 Jan 1990 and was superseded by CAO 101.55. CAO 95.25 aeroplanes can still be built if they were approved before the order was cancelled.

28-XXXX

These aeroplanes are CAO 101.28 aeroplanes to CASA approved specifications (known as an ABAA) and built under SAAA supervision with MTOW not exceeding 544 Kg and a stall speed in the landing configuration not exceeding 45 kt. Private operations only.

32-XXXX

These aeroplanes are CAO 95.32 aeroplanes. CAO 95.32 is the order covering weight shift aeroplanes such as Trikes (known as "Microlights" in Europe) and Powered Parachutes. These must be commercial in origin, either in kit or fully built form and are to conform to a CASA approved design standard and manufacture. The MTOW for a Weight Shift aircraft must not be greater than 450kg and the stall speed must not be greater than 45kt. For a Powered parachute, MTOW must not be more than 300kg and the stall speed must not be greater than 10kt.

55-XXXX

These aeroplanes are CAO 101.55 aeroplanes; certificated, factory built. There are two versions of these. The first has a MTOW of 450 kg, stall speed in the cruise configuration is not to exceed 45 kt, in the landing configuration 40 kt and straight and level speed under full power is not to exceed 100 kt. The second has a MTOW of 480 kg, stall speed in the cruise configuration is not to exceed 45 kt, in the landing configuration 42 kt if and only if the product of the square of the landing configuration stall speed and the MTOW does not exceed 768,000. Straight and level speed under full power is not to exceed 100 kt but may be approved with a flutter substantiation. Can be used for training.