License to certify microlight engines??

[TURIN]

I apologise if this has already been done to death on here but I have done a search or two and not found want I need.

Question:-

Does one need a CAA LWTR or EASA (equivalent) to certify overhaul and maintenance on microlight engines?

Specifically Rotax series for flexwings.

Ta.:ok:

[VP959]

No. Microlight engines are uncertified and all that is needed to work on them is a degree of competence. Owners are permitted to do their own maintenance, including completely stripping and rebuilding the engine. Log book entires are required for engine maintanance though, just like a GA type.

Spares are best procured from the OEM or agent as microlight engine spares. Some, like Rotax, use different parts and inspection standards on parts destined for microlight use rather than leisure vehicle use.

Some Rotax parts are common to the same engine model used in snomobiles, jetskis etc, but without detailed knowledge you are better off sticking to parts from the microlight engine dealers.

[TURIN]

Thanks VP, appreciate that.:ok:

[cubflyer]

VP959,
you may be correct for microlights under the BMAA authority, but I doubt it. Certainly this is not correct for any under PFA authority.
Yes, the owner can work on an engine on a PFA aircraft, but their work has to be signed off by a PFA inspector. As does any work on a PFA aircraft, except similar things that you can do as "pilot Maintenance" on a C of A aircraft. Also if your rebuild includes splitting the crankcase, then your PFA inspector has to get a written approval from PFA engineering to inspect and sign off this work. This approval is required for every individual engine.
I would guess that similar rules apply for BMAA aircraft, so TURIN, I suggest you contact the BMAA and ask them.

[Pilotage]

The issue on microlights is not who can maintain the engine (anybody can), but who can certify that maintenance. In general it needs a signature from whoever did the work, and a second signature from one of (a) A BMAA inspector, (b) the owner, if it wasn't them who did the work, or (c) another PPL if it was the owner who did the work, or (d) the aircraft manufacturer.

The LWTR or equivalent clearly means you'll probably know what you are doing (that said, I doubt the course covered 2-stroke engines in any great depth), but gives no special privileges in the BMAA system.

I agree with Cubflyer about asking the BMAA, but there is also a lot of information on their website which may contain the answer. Try Technical Information Leaflet 020.

P

[VP959]

Indeed an inspectors signature may be required for the AIRCRAFT (the stress on the word is deliberate) following the work, depending on the work carried out, but that wasn't the question asked. The question asked questioned the need for the person doing the work on engines to hold approval, which I answered absolutely correctly.

I did point out that the logbook would need an entry, but assumed that the questioner would know about counter signatures for certain types of maintenance on microlights.

Microlight engines themselves are not subject to certification or control, irrespective of the association that happens to look after them. Many were originally converted snomobile, jetski, motorcycle or other non-approved powerplants, so by definition are not exactly subject to conformity processes in any meaningful way.

BCAR Section S, the airworthiness standard for microlights, says little more about powerplants other than they shall be demonstrated to be fit for purpose.

[Algirdas]

TURIN,
I believe VP959 to be 100% right. You can do whatever engine maintenance you like, and just need to detail it in the in the log book - no other signatures necessary.

However, one thing that has not been mentioned is the requirement for parts - I'm not sure on engines, but any airframe parts (e.g. bolts) need to be traceable to source, and manufacturer certified to the standard specified. Worth checking with the BMAA if you intend to source parts from anyone other than an aviation parts supplier.