Nigel R

https://www.riolettcustomaerosols.co.uk/ Look interesting. Especially for the spray gear challenged among us (i.e. me).

New old stock, though... any idea what the shelf life of clearcoat is? I'm using Rustins, but only for engine bays and so forth. It certainly stinks much about the same as the old 2-pack proofers. Poly-C gets good press as far as I can tell.

Don't use it, replace it. Even if it's fitted to an airframe, there must be a way to get the old outer out and a fresh replacement in.

Did it start off with them? I suspect, a winglet might be a "somewhat" simpler retrofit, as compared to extending wingspan. Certification of upgrade may be easier for a 'bolt-on' as the wing itself doesn't have to undergo a complete re-cert.

The military tend to have other considerations at the top of their list, such as radar signature and ordnance capabilities, rather than fuel burn. Whilst that is somewhat important, it's not the headline that it is for commercial jets and does not dominate operating cost as much. Fuel burn is the absolute key selling point for an airliner. It dictates profit for the airline. Business jets have a significant "my ones bigger than your one" content. Top speed, range, amount of widescreen TVs and sofas (or whatever the current 'luxury' things are). Fuel burn feeds into range, so it's very important. However, if winglets are the fashion choice, that's what they'll have. Maybe in twenty years they'll switch to longer thinner wingtips. Airliners have one other very significant factor affecting the choice of winglets (or other wing designs) - the max wingspan that can fit in an airport gate. Airliners could have wider flatter wingtips that work (mostly) about as well as winglets - but then they have to fold up before the airplane parks up (see the 777X):

Probably late to this but... Discharging via an external load won't stress the charger much differently to charging. It's simply switching a load on / off. Internally, well, the case dissipates heat, the fan aids it, and the charger monitors temperature. Discharge rate will be set to keep things under control. Without knowing more I'd trust the manufacturer to limit this to something sensible. My bigger charger limits it to 20W (despite being a 300W charger) which doesn't take a very big fan or heatsink to control. You could always point an external fan at the unit if you're worried.

Bit late (whoops) but RCC done and cert uploaded, so that's me done until 2030. As an aside, if anyone is going to do the CAA DMARES test instead, there seem to be numerous sites out there with a cheat sheet. Could not be easier.

I wouldn't suggest spruce for crash resistance - "no such animal". Spruce is simply a consistent wood. If you're happy that you have good hard balsa spars then just use them. If you're not happy grading them or you bought a kit and the supplied spars are soggy soft, then replace them.

Super 60s have a fairly lightweight structure to start with. Lots of air, occasionally punctuated by balsa sticks. I note the Colin Usher redraw of the plan shows 2 dihedral braces per spar, for a total of 8 braces: https://outerzone.co.uk/plan_details.asp?ID=4059 This would be plenty strong, I think. Whereas the Ben Buckle version has fewer braces. 5, according to: https://outerzone.co.uk/plan_details.asp?ID=552 As a quick fix in this area only, I would either do what Piers suggests, and put a full depth brace at the front, or add the extra braces at the rear. (mind you, I'd probably not build the thing that much like the plan in any number of places, I'm more of a fan of D-box wings and slab sided fuselage construction)

Running an incandescent bulb at half its rated voltage results in something like 40% of full power, IIRC. You would need to measure the bulb with a multimeter to get an accurate figure though.

but how do you get the new servo in?

Question to you Andy I've rejoined via usual club membership, the club put my CAA reg through via BMFA. I can see my CAA expiry is in around 11 months time. However. CAA have just emailed to tell me my operator ID has expired. Do I need to worry about this?

Balsa is fine but you need the right grade (i.e. rock hard). If you build from a kit, you might get something soft and soggy instead of the hard grade that you need. Whereas, spruce is a safe choice. I had a Junior 60 (the predecessor) for ages, with a small four stroke in. It had much the same construction (which always made me a touch nervous in tight loops) it had more flights than I can remember and was then passed on to several further owners after me.

'feed of oil back into crankcase'... The FL70 has a standard four stroke crank vent nipple - the special silencer just makes a way for you to route the occasional drop of oil straight out the exhaust. Could you get the same result by running a few inches of silicone tube out to where the exhaust outlet is? (happy to be corrected if I'm wrong about the vent being a standard thing)

Coming together fast!