55" Span radio control Aviation Traders Carvair, a lifetime in the making!

[martin collins 1]

A little bit of history first, when i was in my early teens my brother and i would get packed off to our grandparents in Hadleigh, Essex for two weeks during the school summer hols, i was building the usual Keilkraft rubber models and gliders back then. My brother and i were both interested in aviation and our days were spent either over at the modelling strip on One tree island (someone correct me if the name is incorrect) or at Southend airport, the main carrier there being British Air Ferries. The main aircraft in and out were Viscounts and Heralds but the aircraft that we most looked forward to seeing were the BAF ATL Carvairs, what`s not to like, 4 noisy radial engines, an interesting lumpy front end (years before the 747) and most of them had interesting names, Porky Pete, Plain Jane, Big Bill and Big John are a few that i remember. You could hear them coming anywhere in the Southend area and we would lay awake at night listening to them growling in on a low approach to the airport. 

Since getting into r/c about 25 years ago i have always wanted to have one to fly, no chance of a manufacturer producing one and no plans around to build from, besides a lot of drag and probably marginal on weight using wood unless it was built VERY big. About 10 years ago i was lucky enough to purchase a 100" control line Carvair that was built in the early 60`s by two guys who ran a model shop in Leigh on Sea just outside Southend, this was flown at a number of Country shows before being retired and hung up in their shop `Wings & Wheels.`It was eventually bought by a full size Carvair Captain and hung up in his dining room, i purchased it from his daughter who was selling stuff for her mum following his passing, getting it home was a challenge as it is one piece! Again thoughts turned to building a flyer but the practicalities and lack of plans put it on the back burner again. My flying buddy John who sadly passed away last year knew how much i hankered after one of these and having seen the control line model a number of times set about drawing up some plans for a depron version scaled down, he had scratch built several much smaller depron models which at that time i had not attempted. He was at the time of his passing working on a revised set of plans as he thought the originals he had done may not build up correctly but he was gone before he could complete them so i will have to work from his originals.

So here we are, my new foamboard project, 55" span, he had drawn them for retracts and flaps but using the lessons learnt from the ME109 i hope to build it light enough to not need the extra weight and complications of flaps and it will be a hand launch, again to save weight. If this model proves to be successful i will scale it up and add the retracts and flaps, if it proves unsuccessful it will be repaired as necessary and hung up in my house.

 

So, first question is at that size, four engines or two with wind milling outers? Again, thinking weight here, two extra motors and ESC`s, it will probably be on a 3 or 4s pack. Any recommendations or thoughts appreciated, a lot of drag so it certainly won`t glide well! The picture here is of the Control line one hung above our stairs.

[Trevor]

Interesting project. I would go for the 4 motors - they will be pretty small and light so don’t go above 3s or you will find it hard to find a small motor with a low enough kv to turn anything other than a very small prop.

[Paul De Tourtoulon]

Wings and Wheels that's where I bought my russian 2.5cc diesel and later my Futaba 'M' in the early 70's before moving to France, the shop owner looked like David Essex, I spent the first 8 years of my life living in Rochford near the entrance of the Airport where my Parents both worked.

I have a Lancaster around the same size, 4 brushless motors two of each running  on 2 x  3S 2200mah lipos, all the props running the same way !.

[Paul De Tourtoulon]

I always fancied a Bristol Freighter, my first flight in a plane to France,,

[Graham Davies 3]

Great project Martin, and great back story. That's what brings these projects alive.

 

I'd go for 4 motors, and if it were me, slightly larger. I think I'd use one width of foamboard as a centre section with a width for each wing panel, giving me around 80" span. A set of 4 smallish motors would fly it really well.

 

However, at 55" span (I work on foamboard widths!) or thereabouts, it will still be impressive. And you already have a plan drawn up so makes sense to start here. My Ki45 is 60" with the wingtips and uses a single 3S 2200 pack. I get 4 1/2 minutes and it flies really well. Also hand launch and no flaps. The reason I'd go bigger is so I could make the centre section one piece and add retracts, just because! I have an idea how to fit retracts on twin/ four engined 'boarders, as yet unproven, so drop me a line!

 

Given how you finished the Emil, this is going to be brilliant. Watching with great interest.

 

Graham

[Eric Robson]

A great and unusual subject Martin,

I found keeping about 60" span fits in the car easy fly's on one battery one piece model a handy thing.  I fly my Me 110, that fits these parameters more than any other electric model. My foamboard Mosquito is 71" span and a two piece model which I have had to reinforce the wing mounting after a while, it also takes two batteries so half the flights of the 110. Now the building season is here I will get back to the B25 and another foamboard model this one with 4 motors, although another twin may emerge first if I can make the T tail rigid enough with foam board.

Graham, have you tried a 3s 3000 in the Ki45? I get 6mins + with the 110.                                                                                                                                                                        By the way , Emil has Gustav's wings! 

[Graham Davies 3]

Evening Eric, you well?

 

I'd indeed try 3000 3S packs, if I had any! I'm OK with the timer set to 4 1/2 minutes. I usually have 30-40% left and I have an incredibly short attentio... Look! a squirrel!

 

What were we talking about?

 

Graham

[Eric Robson]

Was it a red or grey squirrel?

I am well thank you, I find when I am  reading I drift off and get to the bottom of the page and think what have I just read but I am happy to fly a plane for 15 to 20 mins unless my fingers are cold which up here is quite often. 

[Basil]

You got it right .,.;One Tree island:  Long time since I saw a Ref of it,Bas

[Paul De Tourtoulon]

9 minutes ago, Basil said:

You got it right .,.;One Tree island:  Long time since I saw a Ref of it,Bas

No you are wrong it has always been called Two Tree island, although I have noticed any trees there, I used to fly there as my Brother lived up the hill from there, and launch the boats from my fathers factory there around 1968, not forgetting that I built a 23.6" boat in an old wooden lighter also there.

 

 

 Lien,,,https://www.essexwt.org.uk/nature-reserves/two-tree-island

Edited October 18, 2022 by Paul De Tourtoulon
Lien

[Basil]

I stand corrected. Long time ago. Bas

[martin collins 1]

Gonna need a bigger building board! Let the building begin, gonna require a fair bit of thinking as i go along due to the plans needing a bit more work. My pal John was working on them when he suddenly passed away last year. REALLY pleased to be having a crack at this, i've wanted an r/c forvever, it will be a labour of love. 

[martin collins 1]

One thing i am debating is putting a rudder on it, normally on a hand launch model i leave it off to save the weight of the servo/ linkages etc but as the full size had a lager fin added to help counteract the aerodynamics of the nose and the fact that this model has 4 engines probably all turning in the same direction i think it would be prudent to add a rudder servo, if i need to add trim to the model it could be of benefit. 

[Graham Davies 3]

Definitely Martin. The weight penalty is tiny compared to the advantages.

 

Great project!

[martin collins 1]

All the fuselage, tail and fin parts are now cut out, this will be built before the wing, the plans were drawn as a one piece model but with a 55" span and a fuselage that is almost as long it will have to be removable for me to transport it. Another area i am mulling over is the covering/finish, it will have to be gloss, most of the airframe skin will be in white depron so brown paper/PVA is one option, does gloss paint go well on that or does it soak in a bit and matt off? Profilm or similar is another option, anyone got another option that might work well? Not looking forward to covering the nose area what ever i use, so many different curves with differing radiuses! Is there a product that would just brush on and give a smooth finish which would take spray on paint, that would save a lot of time and swearing this end 🙄 

[Graham Davies 3]

Hi Martin,

One method I was pondering for the CAP232, and will do next time is to cover with BP/ PVA, spray with emulsion and then cover the lot with laminating film. That will protect the paint and give a gloss finish...

 

Graham

[Eric Robson]

 Graham, Martin I would be wary of using lam film on foam or paint as it needs a high temp for adhesion. Profilm may be ok as it works with less heat.

[Paul De Tourtoulon]

I paint everything in matt paint as it covers better and dries quicker then varnish it,

the only thing I paint in gloss are the scrapes on my wife's blue Fiat 500🤐

[Ron Gray]

You can use lam film on foam, just go easy with the heat. A lot of foamie wings are covered that way as is the wing of my Spatman 

 

[Graham Davies 3]

Cheers Eric, Ron.

 

Still to be trialled; we'll see how it works out. As with everything foam, if it doesn't work, it's cost virtually nothing.

 

Graham

[martin collins 1]

Exactly, just had to cut a new crutch floor, the one my pals plan was too narrow to fit the rest of the cut parts. Measure what would fit and cut another, so cheap to build using this material. i have started glueing now, will take some progress pictures later. I have a LARGE stash of balsa kits, seriously considering copying the plans and selling a lot of them. When i do get round to building that model i will do it in foamboard/depron. I still love building with balsa as well so would keep some but the weight saving on the model plus the cheapness/speed of construction of foam building has so much going for it. 

 

 

[Outrunner]

I've covered depron with laminating film, it will adhere well with the iron set about 110°C 

[RICHARD WILLS]

Martin , I couldnt quite see if you have settled on a motor configuration yet , but may I suggest googling for drone motor sets ?

Bang good have quite a few . If you are going for "dead outers in instead , make sure they windmill . Will work just as well . 

[martin collins 1]

I was thinking of using the small Blue Wonder motors, i will wait till most of it is built and see how the weight is looking before finally deciding on 3 or 4s and which motors/props to use, 3 blades may cause an issue when belly landing but the diameter for two blades is obviously limited by the proximity to the fuselage of the inboard engines. Working on it again this evening and if all goes to plan should have some good progress to show.

[martin collins 1]

Had a good evening on the Carvair tonight, had to remake 4 half formers due to notch cut outs shown on the plan which were not needed which dropped them too low but hey that is a minor issue. Really pleased the head scratching has paid off and it is all fitting together, the rest of the formers and the horizontal spine all fit and can be glued on fairly quickly. Once i have all of that on i will build the wing and make up a method of detaching it as the plane will be too big in one piece for my car, the fuselage wont get it`s skin till i know the wing fits properly that will save scuffing or damaging the depron skin. I am going to fix in thin ply to the upper wing saddle to strengthen that area and the lower part of the fuselage that will be under the wing will be cut off and glued to the lower wing skin. Fuselage will be covered in 3mm depron, the wing has a ply/foam spar and wood for the motor bearer/mounts, not sure whether to use 5mm or 3mm wing skin yet, probably go with 5mm depron, the ribs are not flat bottomed and have quite a curve so i may not be able to use the board i used on the 109 with the inner paper removed. I will experiment and use the best strength v weight option. More pictures tomorrow evening, should be finished on the fuselage for the moment by then.

Edited October 22, 2022 by martin collins 1