Proposed amendments to CAO 95.55 - Removal of the 45-knot stall speed limit for certain sport and recreation aeroplanes – (CD 2204OS)

From to 23 March to 13 April 2022 we sought feedback on the Proposed amendments to CAO 95.55 - Removal of the 45 knot stall speed limit for certain sport and recreation aeroplanes. The consultation asked if the removal of the 45-knot stall speed limit for lightweight aeroplanes would, in relation to the operation of these aeroplanes under Approved Self-administering Aviation Organisation (ASAO) administration, maintain an acceptable level of aviation safety.

About this consultation
CAO 95.55 was amended in December 2021 to support the commencement of the new flight operations regulations. Added to the scope of the CAO were lightweight aeroplanes that can have a maximum take-off weight (MTOW) of 760 kg and a maximum stall speed of 45 knots. Consultation to increase the MTOW to 760 kg recognised there was further consultation to conduct in relation to the 45 knot stall speed. That was the purpose of this consultation.

Sport and recreation aeroplanes that are the subject of CAO 95.55 are grouped into ultralight aeroplanes, light sport aircraft and lightweight aeroplanes. These groupings are based on the aeroplane's maximum take-off weight (MTOW) and the airworthiness standards to which the aeroplane has been designed, including its landing configuration stall speed.

The focus of this consultation was on the safety aspects of removing the stall speed limitation from the definition of lightweight aeroplane.

The aim of the proposed changes to CAO 95.55 is to provide greater flexibility to the sport and recreation flying sector, as it will provide for a wider range of aircraft that can now be utilised, some which had been previously excluded.

In total, there were 134 respondents to the consultation. Responses came from various groups (some respondents said they were associated with more than one group); 87 identified as being sport and recreational aircraft owners or operators, 87 identified as a pilot of sport and recreational aircraft, 65 identified as a Part 61 licenced pilot, 27 identified as being a sport and recreational aviation maintainer or organisation, 2 identified as a maintenance engineer or a CAR 30 approval holder, 15 identified as being a flight school (sport and recreational aircraft - other than gliders), 2 identified as being gliding clubs and 2 identified as being a sport aviation body or as a prospective ASAO. Of the submissions, 95 consented to allow their responses to be published and 39 requested their submissions to be confidential.

Summary of feedback
Most responses (80%) agreed that the proposed change to the light aeroplane definition would maintain an acceptable level of aviation safety in relation to the operation of lightweight aeroplanes under ASAO administration.

For the rest of the respondents, who either disagreed or agreed to the proposed amendments with changes, the common themes across their feedback were:

Theme 1 - Pilots - scope of aircraft, pilot competencies and medical
Feedback in support of the proposal but with changes mentioned the following benefits:

• Broadening the range of aeroplane types greater than 600kg available for operation by pilot certificate holders.
• The removal of a barrier to entry to recreational operation of sport and recreation purposes for aeroplanes with stall speeds greater than 45 knots that are suitable for sport and recreation purposes, potentially contributing to arresting the decline of GA by broadening the suite of aeroplane types available to the recreational sector with its more relaxed pilot medical requirements.

Feedback opposed to the proposal mentioned the following concerns:

• An increased level of discomfort in relation to pilot competencies and operation of aeroplane types greater than 600kg with stall speeds exceeding 45 knots that are not training types.
• Landing incidents are not unusual with light sport aircraft and increasing the light sport aircraft allowable stall speed will only increase the accident statistics as it relates to LSA.

Theme 2 - Aircraft - certification and maintenance
Feedback in relation to certification mentioned the following issues:

• Concern that increasing the stall speed lowers safety standards by not simultaneously amending the certification basis of aeroplanes to increase structural integrity.
• The potential safety benefits that arise from modern advanced technology. The change in stall speed will encourage the introduction of modern more technologically advanced aeroplane designs which will, over time, raise the safety profile for these aeroplanes.
• The relationship between stall speed and MTOW. Clarification was sought on the operation of aeroplanes up to MTOW in accordance with their certification.
• That the structure around and in front of the occupants must protect the occupants from injury, in the event of a crash at approach configuration airspeeds.

Theme 3 - Administrative oversight by ASAOs
Feedback in relation to administrative oversight highlighted the issue of pilot competency and the role of the ASAO, with the following mentioned:

• That pilots of lightweight aeroplanes should be competent to operate the type of aeroplane, including the upset recovery techniques applicable to the type.
• That the pilot training, maintenance oversight and most importantly culture of these organisations must be appropriate for the safe operation of these aeroplanes.

CASA's responses
While there were a few responses which disagreed with the proposed amendments, overall they were generally accepted. CASA is satisfied that because the change applies only in relation to lightweight aeroplanes for which a certificate of airworthiness is in force and not to light sport aircraft or ultralight aeroplanes, most of the safety concerns identified by the submissions are acceptable and can be managed within the existing CAO 95.55 framework.

For lightweight aeroplanes, CASA agrees with the responses regarding the need for pilot training to include a broader range of skills. CASA supports greater pilot and organisational responsibility for general competency in relation to the operation of heavier, faster, and more complex aircraft. CASA agrees that, with the expanded availability of appropriate training types, the competency standards for pilots of these aircraft should encompass training not possible in the LSA/ultralight group, including the training of instructors in the demonstration of stalls, spin avoidance, and recovery techniques in lightweight aeroplanes to pilot certificate holders where appropriate for the type.

CASA also observes that this expanded capability is likely to have a flow-on safety benefit to the sector as more pilots will gain exposure to these kinds of manoeuvres and handling considerations. This was identified as one of the benefits of the earlier proposal to raise the MTOW for light weight aeroplanes covered by ASAOs.

CASA is dedicated to assisting ASAOs to build capacity and capability in delivering outcome-based flight training and the further promotion of a safety culture within the recreational sector. Mechanisms to address these issues have been drafted for the proposed Part 103 Manual of Standards.

In relation to aircraft certification, CASA notes that the removal of the 45 knot stall speed limit for lightweight aeroplanes has no impact on the certification status of the aeroplane. Any lightweight aeroplane to which a certification standard that includes a stall speed limit applies, would be constrained by that limit.  For example, if an aeroplane is certificated to JAR-VLA/CS-VLA, the 45 knot stall speed would remain as a certification limit for the aeroplane. For lightweight aeroplanes which are not certificated (amateur-built aeroplanes) the stall speed is determined during the aeroplane's flight testing and is dependent on the aeroplanes design and construction.

Next steps
CASA thanks the many highly qualified people and organisations contributing their time and thought to this consultation and acknowledges the feedback as beneficial to the effectiveness of the consultation process.

Based on industry feedback, CASA will proceed with amending CAO 95.55. The amendment will include:

• removal of the stall speed limit; and
• inclusion, as appropriate, of requirements in relation to competency standards and units of competency for the operation of lightweight aeroplanes, including for the flying training mentioned in section 11 of the CAO; and
• minor mechanical changes to correct existing errors and omissions.

In addition, CASA will investigate the development and promulgation of further educational tools to assist ASAOs further enhance their competency standards, flying training and safety culture.