DocPrinter

Hello again! I'm a beginner flyer, had set up to learn on a foamy, but the wind conditions at the site are limiting my potential flying days. I am therefore advancing a long term sky 40 repair project. It is being converted from IC to electric. I'm ready to glue on a new firewall. I've two schools of thought on getting the thrust angles set. 1) Glue on setting it up by eye. Request a club member to test fly it. Trim the motor mount from the wood with shims/washers until test pilot happy with it. 2) Glue on setting it up by eye. Set up plane on table (without landing gear or wing) and level so that rear tail plane is parrallel to the ground. Measure firewalls angle from vertical and note offset required to make down thrust angle. Roll fuselage 90 degrees level based on tail fin. Repeat checks on firewall for side thrust angle. I'm inclined to think that there is too much scope for measurement errors to creap in with approach 2 and the best approach is likely be 1. I assume the plane won't be unflighable with the thrust line out a bit, just a bit if a handfull under throttle? Step 2 assumes the tail plane and fin would give suitable 0 degree datums. I realise some models have a bit of incident on the rear fin to account for downwash from the main wing. I'd assum this more likely on short tail plane moment (relative to the chord of the wing rather than raw mm or distance) models like fun flys.

Thanks all. Going to stick with trike setup. Few bits on order to replace missing items.

Thanks for the comments all, some food for thought, and found a good diagram on positioning of landing gear if I do comit to a tail dragger. Guess a bonus of the trike is the gap where the throttle servo was could be repurposed as a nose wheel servo and rates etc could be independent of rudder. Which ever way I go I need to get bits as the nose gear that was on it was not right for the plane. That said, one nose wheel assembly and a wheel is cheaper than a full tail dragger undercarriage set.

More variables than I had anticipated: https://www.balsaworkbench.com/?page_id=926 In the interest of getting this back in the air sometime soon I think sticking with trike maybe the appropriate answer.

Cheers, asked to make sure I wasn't over or under speccing my mod. I'm guessing the ~6mm firewall ply is overkill, what would be advised?

Hi All, Restoring a Sky 40 and am mostly in favour of converting it to a tail dragger. What are your thoughts, especially those who use Sky 40s on grass strips? I did notice the XL version is steerable tail wheel right from the plan. What should I do to mount the main gear? I was thinking strip off some of the balsa sheeting where it bolts in and glue on a double skinned piece of lite ply. That with load spreading on the nut/fastener side sufficient? Thanks!

Not much use now as it seems you have another kit but DB sport and scale has a built up wing kit (as in the wing on its own) for the mascott. Seems the mascott is the kit to have on the shelf! I got one myself too earlier last year. Just got a fuselage jig and want to get the wing kit before I start on it as the veneer wings seem to be the only bits in the kit that have degraded. All that said I've a part restored Sky 40 to complete before I start.

I should have said version 10.x/evolution via Steam. Thats what I am on. Hoping there is an update soon to sort out a few irritations with the new user interface. Par for the course I guess with a significant interface refresh, but couldn't have had much of a testing phase.

It was folk pushing their luck, and not being held up for it. Doubt the organisers would have designated the largest undercover area as a shared space for smokers and non-smokers. Not sure they could have done if they wanted to as I think it needs to be more open than that.

I might have stayed longer but when you've a seven year old shivering because he's soaked through, a 3 year old in a similar state, a wife doing her best to appease them and and folk smoking/vaping in the main shelter tent we had to call time on it. If weather is looking better next year we will be camping. If on the edge we'll get a family order of wellingtons in!

Ok, that's odd. I have no way to send messages, or anywhere obvious to adjust message settings. Do you need subscriber ID before you get messages? I buy the magazine occasionally, rather than subscribe. I'm DocTrucker on RCGroups if you are on that forum too?

Regards the offer, that's great! Regards my message box that is very odd, I shall check settings, but haven't purposely turned anything off!

I recently identified a second hand model aeroplane that I aquired last year as a SLEC (Tony Nijhuis) Sky 40. I got the July 2006 RCM&E for the original article on Tony Nijhuis's Sky 40. Didn't realise it was split over 2 magazines! I assume part 2 is in August 2006. I'm interested in the plan and article to add to my records, but will be buying a copy of the current plans from SLEC soon. If anyone has the magazine or digital scans of the article and original plan (which I assume covers the wing) I would appreciate a copy. Thanks!

Just wondering how realistic the simulator is again. Specifically regarding stalls in turns, control reversal stalls on approach on slow landings, and elevator induced stalls. I've had a few hours on it now and not really noticed any pronounced sharp stalls. Mostly been on the Wot 4, Aprentice, the foamy high motor pusher, Avistar, and a little go on a funfly. Mostly focusing on the Avistar just having a crack at the basics on the others when enthusiasm lulls on circuits and bumps with the Avistar! I do struggle with location on approach / depth perception, but I think thats alot to do with trying to play on a piddly laptop screen. Did try VR over wifi6 with the Pico 4 but the plane was very juddery. need to get a decent USB C cable and try again.

Pretty sure the evolution release is 10. As far as I can tell it's mostly a user interface update.

One of the biggest gotchas in FreeCAD - which the OP has evidently copes with - is for a sweep/loft to work best there should be an equal number of elements in each sketch, and they are in the same order. Badly jumbled sketch elements can create some unique results! FreeCAD is a very powerful tool, particularly for an open source package. It is however worth remembering it hasn't quite made release version 1. One of my biggest grumbles with proprietary CAD is in some ways it is a step back from the days when engineering drawings were freely exchanged. Now to get the best of CAD's strengths you really need to be using the same software. The longer you've been using one program, the more you get tied to it with your library of old CAD getting bigger and bigger and tied to a specific vendor.

@Martin Harris - Moderator that came across a couple of shades harsher than I intended. No issue with extra detail or clarifications, it may help show up something I've overlooked. In fairness I should have asked on the Ardupilot forum, as the stall speed parameter is often tuned by advanced users. I do enjoy collecting extra detail around my hobbies which allows me to better understand the patterns which we observe. I have largely given up on a pet project of a 1/8th live axle rc car racer through getting fed up with just drive it and see style of responses when throwing out calls for extra detail / first hand accounts around specfic questions. Sure some folk don't need/want to know the specifics but there's no need to discourage others from asking.

Load of people going off on tangents here. Simple question looking for a range of stall speeds for typical trainer. This was answered in the first reply. I've got what I was looking for thanks.

@Piers Bowlan nope was just curious and looking at the figures but had no idea on rough stall speed.

@GrumpyGnome was just curious and looking at the figures but had no idea on rough stall speed, as I guess is the case with many modellers without GPS or pitot tubes! Many motor specs that I've seen recently quite output power. Had to do some digging to find thrust values for some.

@Piers Bowlan you caught a few phone related typos which I will correct. Vertical flight with an air speed above stall is still low alpha, or pre stall. I just wanted ball park figures for stall speed to see what the power requirement is simply to lift the weight of the model at a low not stalled speed, which would appear to be about 15mph. ...or I won't edit as it won't let me any more!

I have finally identified my random rebuild project that's been on the back burner for a while. Thought I'd posted here put it was on another forum which I'd forgotten about: https://www.rcgroups.com/forums/showthread.php?4364921-Can-you-help-identify-this-trainer SLEC Sky 40. Anyhow what you've given is enough thanks. I was curious what the minimum pre drag power requirement would be if you wanted to maintain a slow speed straight up without looking speed just based on the rate of potential energy increase. True figure would be a few notches up on that as it wouldn't allow for drag. I wasn't sizing my motor based on that, I'm using the 220W/kg trainer to 330W/kg aero guide from Steve Webb Models.

Evening all, Crunching some numbers for my own entertainment, nothing critical. What are ball park figures for stall speed of a typical 1.5m high wing balsa trainer with no flaps and semi symetric section? Appreciate it can vary substantialy with wing section, shape, and general design. Ball park is close enough! Cheers.

Today was a different story. Fairly close, left home about 0750, onsite 0920, family soaked through by about 1030, left site and home around 1200. Gutted. That said rain didn't stop until J18 on M6, so don't regret early dart.

@GrumpyGnome glad to hear it is close on flying characteristics. Regards not polished I'm referring to the user interface which I find very much on the clunky side. For instance: My version doesn't seem to let you scroll through previewing the aircraft choices because as soon as you preview one that has colour choices it snaps to the colour choice page and cancelling that clears the menu. Likewise wind settings seem to be in two different places. Flight wise it seems very similar to Picasim (which is reassuring) but far more tollerant to damage on landing.