Mods to a permit aircraft

[douglas.lindsay]

I'm looking into a possible purchase - my first, so I feel rather naive :) It's a permit plane being sold by a mighty nice bloke. It has a 582 installed at the moment but the sale includes a reasonably youngish Jabiru 2200. If I bought it, I'd want to change the engines over before I did much time in it - seems silly not to take advantage of the extra power and possible higher MTOW since the Jab would seem to be only a couple of pounds heavier. Plus I'm not sure I want to learn too much about maintaining a 2-stroke right now.

My question is - has anybody got experience of changing engines, and getting the necessary approvals? How long is it likely to take to get through the necessary paperwork, and what all is involved (besides the spanner-related activity of course)? I know that the application fees for a mod are £45 but what else would I need to budget for? Or is it just a daft idea that I'd do well to stay clear of?

This is all, of course, dependent on me being able to persuade the wife that I'll spend less over the course of the next 12 months if I shell out a lump of dough now!

[Maoraigh1]

If you're not already an LAA member, join. Then contact the engineering dept and ask about the specific aircraft and engine.

[gooneydog]

daft idea that I'd do well to stay clear of

[Genghis the Engineer]

I've lots of experience, but to give any meaningful advice, can you tell us what the type is? If you don't want to be too public on here, PM me the registration.

G

[Mark 1]

If there is already another example flying with the configuration that you want, then it could be reasonably straightforward to go on the back of that previous mod approval. Likewise, if you are changing to another configuration provided by the manufacturer (or designer) and convert to that exact specification, then there shouldn't be too much difficulty.

Otherwise, you would need to demonstrate that what you are doing conforms with an appropriate certification code (e.g. VLA ot pt 23) and that will probably involve more effort and expense than you'd want to expend.

Really a lot better to search out the aircraft that is already close to your ideal.

[Rod1]

Join the LAA ASAP. Find a local LAA inspector (on the LAA web site). Ask him to help you find out the full position. It could be very simple, or virtually impossible and you will need advice. To do the job you will need an inspector anyway.

Rod1

[douglas.lindsay]

Genghis - it's a Rans S6 with the 116 wing. According to the current owner S6 + Jab 2200 has been done before.

I've already got my LAA membership sorted out; quite excited about the possibility of using it for more than just the free magazine!

[Genghis the Engineer]

If you copy the existing modification (likely to need new engine mounts and propeller, as well as the engine) then the approval should be pretty straightforward so long as you're able to get hold of the design details and ensure they're copied completely, whilst your inspector has them to sign it off against.

LAA's likely to require a short test programme, probably 2-4 hours of real testing, and the remainder of probably 10 hours, flown off by yourself.

LAA will probably be able to point you at a suitable pilot to do the testing, but in your neck of the woods, the first person I'd ask would probably be India-Mike.

Expect the cost of conversion to have cost you a few hundred, maybe £500 in bits, paperwork and testing costs and the faff will take a few months.

G

[NigelOnDraft]

Douglas... See LAA Link TL3.12 (http://www.lightaircraftassociation.co.uk/engineering/TechnicalLeaflets/Mods%20and%20Repairs/TL%203.12%20Engines%20and%20Propellers%20fitted%20to%20LAA%2 0Aircraft.pdf)

As above, provided you are following one of the currently approved Type/Engine/Prop routes, should be simple in terms of paperwork. Go off piste, and it all gets difficult :confused:

NoD

[DBo]

Having fitted a non- standard engine to a kit- plane I would day that if you have good practical skills , the engine is approved in the airframe by the LAA and the major parts (engine mounts, cowls etc) are available from Rans then it shouldn't be too hard - especially following a previous mod.

If building ikea furniture fills you with dread or the major parts aren't available then life will be a lot more interesting...

Dave

[douglas.lindsay]

Thanks all.

I'm used to DIY and a bit of car maintenance but I guess I'll need to decide whether I'm ready to ask some test pilot to trust their life to my skills... :ooh: and whether I can really put up with my new purchase being stuck in a hangar for a few months while the approvals get sorted!

[batninth]

According to the current owner S6 + Jab 2200 has been done before.

Yep, quite a few around, we looked at a Jab powered S6 before we bought a 582 one. Opened the throttle on the jab and got to Vne in level flight, not a chance of that in the 582!

As Genghis the Engineer says, follow the LAA documentation posted in the engineering section, get an LAA inspector & you should have quite a few around if you have any queries.

batninth