Locally produced airplane, the ‘Sling,’ has been grounded from flying in controlled airspace, being used for training purposes, commercial flight, flying through cloud or at night.

The sweeping ruling has been made by the CAA (Civil Aviation Authority) and affects all Sling aircraft maintained by The Airplane Factory‘s AMO (Aviation Maintenance Organisation).

You can find out more about the Sling at The Airplane Factory‘s website (here).

According to the letter from the CAA:

In terms of section 116 of the Civil Aviation Act (Act 13 of 2009) your aircraft shall not:

1. Conduct any Commerical operation
2. Be utilised for any Part 141 training
3. Be operated in or into controlled Airspace
4. Be operated other than in VFR by day only

The original letter The Airplane Factory received can be read here.

Below is The Airplane Factory‘s Marketing person, Andrew Pitman’s response, as per Avcom aviation forum:

Note from The Airplane Factory AMO in response to CAA “PROHIBITION ON EXERCISING CERTAIN PRIVILEGES OF ANY AVIATION CERTIFICATE, PERMIT OR AUTHORISATION BY AUTHORISED OFFERS OF INSPECTORS” issued to owners of aircraft maintained by The Airplane Factory AMO (AMO 1264) on 4 March 2015

Yesterday afternoon, 4 March 2015, the CAA issued a letter to the operators of all aircraft maintained by The Airplane Factory AMO, AMO 1264 (“the TAF AMO”). An example of the letter is attached. Although a little confusing, the letter provides that certain shortcomings in the maintenance performed on aircraft by the TAF AMO must be corrected and verified within 30 days. Affected aircraft operating from controlled airspace are effectively grounded, as they may not be operated in such airspace until corrective action is taken and verified. Affected aircraft outside of controlled airspace may be flown, but may not be used for training, for any commercial operations, or flown other than VFR by day.

The Airplane Factory (both manufacturing organisation and AMO) is quite willing to comply with all CAA and legal requirements and has always endeavoured to do so. In fact we commit substantial resources to issues of compliance and we yearn to improve our relationship with the regulator and work more closely and co-operatively with it. We are very proud of the Sling and TAF’s safety record, having built more than 140 flying aircraft, more than half of which we maintain. There has never yet been a single incident or accident on a Sling attributable either to a manufacturing or maintenance failure of any kind on the part of The Airplane Factory.

Notwithstanding this, we are disappointed by the manner in which the CAA has chosen to respond to the alleged shortcomings identified in the AMO documentation and practices. In our view the CAA response is overblown and not proportional to any risk identified. It is irrational and unjustified.

For the sake of clarity, the brief background to the CAA letter is as follows –

On 17 February 2015 the CAA performed a surveillance audit on TAF AMO. The AMO maintains 73 Sling aircraft manufactured by The Airplane Factory.

During the audit it became apparent that the inspector was dissatisfied with various aspects of the AMO’s paperwork and certain of its practises.

The inspector was particularly concerned about two issues he identified. These were firstly the failure of the AMO to perform annual static and pitot system checks on using the methodology set out in the CATS, Part 43. This methodology requires the use of a pitot static test instrument calibrated within the past year in accordance with specific requirements. The other major concern was that the MPI and service checklist used by the AMO in maintaining the aircraft does not disclose all of the requirements set out in Annexure A to Part 44 of the CATS. (CATS Part 44 regulates maintenance of NTCA aircraft).

In regard to pitot and static port (ie – airspeed indicator and altimeter) testing – TAF has indeed never performed airspeed and altimeter checks using the Part 43 compliant methodology. The TAF AMO (and manufacturing organisation) checklist, however, does require confirmation of correct operation of all instrumentation in the aircraft and, separately, verification of the accuracy of the altimeter for the airfield at the ruling QNH setting. These requirements are required to be signed off by the relevant technician. In addition, all Slings maintained by the AMO have two altimeters and two airspeed indicators. These are therefore effectively cross-referenced in each and every flight of the aircraft. The aircraft also all have a GPS which provides a third cross reference of sorts, albeit from a different source and measuring different variables.

Comprehensive test flights are conducted on all manufactured Slings and on most Slings following maintenance and inspection. TAF has flown its aircraft maintained in this manner twice around the world, once to Europe, once to the USA and back, and we and other owners of Slings have flown more than 20 000 hours around South Africa without a single reported incident, of which we are aware, relating to altimeter or airspeed indictor inaccuracy. Finally, as a question of fact neither the CAA, nor RAASA, have enforced a requirement of annual testing of the pitot and static systems using the Part 43 compliant method in more than 15 years.

It is accordingly TAF’s view that there is absolutely no need to ground aircraft pending the implementation of the Part 43 compliant testing method, if this is indeed required. It would make much more sense to give aircraft owners an opportunity of perhaps 60 or 90 days to have the tests performed, and to convenience them by enabling them easily to fly the aircraft to the location at which such tests can be performed. There is simply no need to act with such a heavy hand, aircraft operators suffering substantial inconvenience and potential financial loss with nothing gained. The approach also sticks a little in one’s throat given the failure by the CAA to enforce the requirement since at latest 1997. Slings in particular are all built with dual airspeed indicators and altimeters and are only flown VFR in VMC. There is therefore no risk of any kind associated with providing a reasonable period within which to have the tests done. (It remains to be seen what approach the CAA adopts in relation to the balance of the NTCA fleet, at least 80% of which must be non-compliant, and many or most of which will only have one airspeed indicator and altimeter).

In relation to the second major concern giving rise to the CAA letter – it is also true that the TAF AMO MPI and service checklist does not match exactly the Part 44 Annexure A checklist. The TAF AMO checklist does, however, include every single item set out in the (CAA approved) Sling maintenance manual. The checklist is also attached as Annexure F to the TAF AMO Manual of Procedure approved by the CAA at the establishment of the AMO and then again at the renewal date. The checklist is in fact far more comprehensive and detailed than the Part 44 Annexure A checklist (it is some 15 pages long), but there are nevertheless some Annexure A items not listed in it. These are a static idle test, a compass swing (required only each 5 years in NTCAs), a weight and balance (also 5 yearly) , the pitot and static test referred to above, and an annual transponder calibration test (to be performed specifically in terms of Part 43 using specific equipment).

In the interests of meeting the CAA requirements, the TAF AMO checklist has now been updated to include these Annexure A requirements.

Again, TAF has no objection at to meeting all CAA requirements. We commit ourselves again to doing so and we beg the CAA to work closely with us to achieve this. We do not believe, however, that the grounding of aircraft in controlled airspace and the immediate prohibition of training flights in affected aircraft is a proportional or rational response to the issues identified, particularly given the CAA’s historical contribution them.

Overall, the most difficult and disappointing issue for The Airplane Factory is the ongoing failure to achieve a meeting of minds between us, as industry participants, and the CAA. We hope and try to work co-operatively with our regulator, and we will continue to do so.

We regret any inconvenience caused to users of the TAF AMO and we will do the best we can to assist you in getting your aircraft properly and fully airworthy as soon as possible. We are now able to perform the required static and pitot tests at our premises and to re-inspect aircraft using the updated checklist. We await final CAA approval of the updated checklist containing the additional few entries set out in Part 44 Annexure A, but hope that this will be forthcoming shortly. Please contact the AMO (011 948 9898 or AMO@airplanefactory.co.za) for advice or to arrange to bring your aircraft in. This must be done before 15 April 2015.

If your aircraft is hangared at a controlled airfield, please contact us if you require assistance obtaining a special flight permit to fly it to the AMO.

Aluta continua.

The Airplane Factory AMO team

You can read the responses on the Avcom forum here.

We will keep you informed as to what happens next, should we hear anything.