.09/.15 NVA at last

Chris,
Do I understand you right? You are also thinking of building this model?

Yes-I have the full size plans and templates of the major parts of the Frog kit-purchased on ebay from vendor 'flyer21uk' a couple of years back...just the plan...so it will be a scratch build. It was going to be a covid lockdown build-but I got distracted building a Luton Minor for FF scale and a vintage model!

Note that this vendor offers a very large range of plans-and his listings are worth a look. Of course in the US you also have vendors 'papalee' and 'airclassix' who also offer a similar service-though with their own specific focus.

BTW I was slightly in error-having just dug the Frog Mosquito plan out from my box of 'near future builds' -it states 'For 1cc to 2.5cc engines'  not the 1-1.5cc I stated earlier....though I imagine it will be no slouch with two 2.5cc....that being said-'Aeromodeller' and 'Model Aircraft' both published quite a few CL scale twins and 4 engined designs in the mod 50s thru mid 60s...though virtually all of these were full plan view type fuselage types not profile...and sizewise most were for 2.5cc.....so perhaps the Frog Mosquito will not be overpowered by two Medallion 15s.  For my part finding suitable props is a far bigger challenge than what to power it with....

Despite being predominantly a Ff er-I do also have a strong interest in scale-so my first venture into CL scale will be the Frog, as here in NZ we do run a profile scale class at our Nats, under the auspices of the FF and CL scale tech committee-which deals with all non R/C scale classes. A more serious CL scale effort will have to wait another year or so-especially as the amount of work involved is hard to justify on something likely to be flown only  once a year

ChrisM
'ffkiwi'

I like your timing...some time in the next two years. Keep me in mind as I'd love to do a simultaneous "buddy-build."

When I contracted Mr. Winstanley to cut mine, I had him adjust the engine bearer spacing for the .09 Medallion, and cut some parts from thinner, lighter material. It is a short kit, so I better get the LE/TE stock before all balsa is being used for windmills. My thinking was based on my BHM profile Mossie. At 27 inches and flying twin Norvel .074s, it really moved, despite being horrendously heavy! Surely I can build a structured/ribbed wing lighter than the BHM wing (well, hopefully).

944_Jim wrote:I like your timing...some time in the next two years. Keep me in mind as I'd love to do a simultaneous "buddy-build."

When I contracted Mr. Winstanley to cut mine, I had him adjust the engine bearer spacing for the .09 Medallion, and cut some parts from thinner, lighter material. It is a short kit, so I better get the LE/TE stock before all balsa is being used for windmills. My thinking was based on my BHM profile Mossie. At 27 inches and flying twin Norvel .074s, it really moved, despite being horrendously heavy! Surely I can build a structured/ribbed wing lighter than the BHM wing (well, hopefully).

There was a prolific Asian modeller resident in germany and scandinavia in the late 50s and 60s-Hoh Fang Chuin who designed a lot of models:
https://www.rcgroups.com/forums/showthread.php?2645118-Hoh-Fang-Chiun

sadly he died quite young-in his 40s...but I've always liked his Saab 18 design...and this one is top of my list of potential builds for a 'serious' CL scale model. I'm not entirely happy with the amount of full size  documentation I've collected for it...and need to decide whether i'll build it as an 18A or 18B variant....most of the photos I have are of 18A versions-but the only existing one I can find colour photos of is an 18B, using DB605 water cooled powerplants rather than the Wasp radials of the 18A...so requiring a redesign of the nacelles.. [the Hoh Fang Chuin plan is of the 18A...]

It's different enough to make people take notice-especially if done with the Swedish colour scheme [well who else are you going to use-they were the only country to operate it..!]-yet close enough to a Dornier 17 in appearance to fool a casual observer.  I could even build it exactly as per the article with a couple of Taifun Hurrikans.....and contrarotating props....though I'm not sure if you'd see any benefit in actual use-and you'd have to find a pusher 7x6 3-blader to do it....

ChrisM

there are 3 blade 7x6 out there > https://www.rchobbies.com.au/prop-7x6-3-blade-800mm-t28-v2

Eric/Balogh,
Thanks for the prop options.

I will consider the smaller one for Miss Mossie II, as the smaller prop may allow for shorter LG.

I would consider a 5x3 ridiculously small to put on an 09-that is a size appropriate for an 049 not an 09

ChrisM

balogh wrote:This is a 3-bladed 5" prop that  keeps the TeeDee09 near its performance curve peak of 18k rpm.

It might turn those revs-but at what efficiency? A 7" two blader would produce way more thrust at the same rpm.....let alone the fact that a 3" pitch is not a good match for a CL model...

ChrisM

balogh wrote:The 3 bladed was recommeded above not for best power but for authentic look. Of course thrust-wise there are better 2-bladed props. I have 7x3 Graupner on my Cosmic Wind and Wonder RC planes both powered by TeeDee09-s.

And its way too small for the intended use-on a profile scale model of the Mosquito-a quick check on the plan with a ruler indicates that both a 7" diameter or an 8" diameter prop will fit-and for scale appearance the 8" diameter comes closest to replicating the frontal appearance of the original-though an 8" 3-blader will be an excessive load for a 1.5 engine....so on reflection, it might make more sense to build the model for two 2.5cc engines....but I'm already committed to two 09s-so will have to settle for a couple of 7x6 3-bladers...in extremis, cut down and reshaped from 8x6's

I'm not familiar with Enyas, although I scored a couple this year. I think that a 6" pitch is pretty high for a "not so old" glow engine. Now if the Enyas have been converted to diesel, that sounds about right. I do know I couldn't tell how many blades the prop was swinging while running, so I started with 2-blade props. I never got to try the 3-blade 7x4 props on the plane. In hindsight, I bet they would be too much for the Big Mig .074.
Admittedly, I'm not trying to win a scale contest. I'm just infatuated with the Mosquito. The BHM kit came to me too cheap to say "No." I was hooked the minute I saw it in the paint, and couldn't stand to not fly it once it saw the first flight.
Yeah, and that wild twin sound! I'm going to rewatch one of the flight vids on the big screen smart tv and crank up the stereo in about 15 minutes.

944_Jim wrote:I'm not familiar with Enyas, although I scored a couple this year. I think that a 6" pitch is pretty high for a "not so old" glow engine. Now if the Enyas have been converted to diesel, that sounds about right. I do know I couldn't tell how many blades the prop was swinging while running, so I started with 2-blade props. I never got to try the 3-blade 7x4 props on the plane. In hindsight, I bet they would be too much for the Big Mig .074.
Admittedly, I'm not trying to win a scale contest. I'm just infatuated with the Mosquito. The BHM kit came to me too cheap to say "No." I was hooked the minute I saw it in the paint, and couldn't stand to not fly it once it saw the first flight.
Yeah, and that wild twin sound! I'm going to rewatch one of the flight vids on the big screen smart tv and crank up the stereo in about 15 minutes.

for a while the Enya 09 was considered second only to the TD09 in terms of power-and slightly superior at lower rpm levels. trouble is there have been so many different models it is hard to keep up-and the various published tests do not necessarily bear valid comparison from model to model. Enyas do have an excellent reputation for longevity and low wear though. I did consider-and even went as far as to acquire several AP Hornet 09 s as possible alternatives-though these would need conversion from R/C to U/C....and I don't really have the time or motivation to mess about finding the right venturi size by trial and error. I'm a bit dubious about the hornet muffler, too-IMO its a bit on the small side....

I agree though that a 7x6 3-blader is a bit much load for an 09 glow....ideally a 7x5 would be about right-but as far as I know such an animal has never existed commercially. I do have 7x4 3-bladers, though and 8x6's....if I use the Hornet 09s, a 7x4 would be entirely appropriate.

Of course I could simply use a 2-blader for flying and 3-bladers for static-but then I'd need 2 types of spinners as well...

I take it you are aware that here in NZ we have been busily restoring and rebuilding Mosquitoes successfully for some time-I think we've finished at least three to date...

see: https://www.youtube.com/watch?v=YkXiOqrXMmI https://www.youtube.com/watch?v=HuMm-SN6geY
https://www.nzherald.co.nz/business/wwii-de-havilland-mosquito-restored-in-auckland-for-armistice-day-air-show/B6MQZPI2HSRLAK4OHK3OB4CQXY/

ChrisM

Chris,
I believe I have one of only two AP .09 CL engines in the US (chuckle). The other was in California a few years back, but I couldn't cleanly connect with the seller. He waffled too much as I was working to push the sale through, so I gave up. I wanted it just in case the appropriate twin showed up.

I read they do better if the stinger hole is drilled out a bit, or removed with the remaining hole opened up. I also read they are heavy for a .09, and weigh almost as much as the .15 variant.

I can provide details and pictures if you think you may want to reproduce the NVA and venturi. PM a good email address, or we'll start a new thread for it.

Jim-many thanks I'll take you up on that offer-PM sent

Chris

944_Jim wrote:I read they do better if the stinger hole is drilled out a bit, or removed with the remaining hole opened up. I also read they are heavy for a .09, and weigh almost as much as the .15 variant.

4 years ago, I took Brad's suggestion and purchased a Saito muffler with 10 mm header pipe, fits my Sanye .09 perfectly.


With the curved header pipe will allow me to angle the exhaust away from the fuselage and wing. With the lock nut, it can be adjusted to any orientation needed.

GallopingGhostler wrote:

944_Jim wrote:I read they do better if the stinger hole is drilled out a bit, or removed with the remaining hole opened up. I also read they are heavy for a .09, and weigh almost as much as the .15 variant.

4 years ago, I took Brad's suggestion and purchased a Saito muffler with 10 mm header pipe, fits my Sanye .09 perfectly.


With the curved header pipe will allow me to angle the exhaust away from the fuselage and wing. With the lock nut, it can be adjusted to any orientation needed.

Now THAT'S a clever idea.....

ChrisM

I played with the APs a bit. Made a needle valve assembly, venturi and header. Also drilled and tapped the exhaust hole bigger and put a 6mm hole in the exhaust. A friend had the control line .09. I looked like the RC needle screwed in above the casting into a machined venturi.
Made some heads for the .09 and .15 that took the turbo plugs too.

Nice work and CL conversion, aspeed. An interesting fact about the Sanye .15 was that it is a touch smaller with .136 cu. in. displacement, which according to an Aeromodeller review, helped to explain its milder running characteristics when compared with other .15 sport Schneurles. By the time I was about to buy one, they discontinued making them and stocks quickly ran dry.

Great job, ASpeed!
Sigh...I'd love to have a hobby lathe.

944_Jim wrote:Great job, ASpeed!
Sigh...I'd love to have a hobby lathe.

I was told many years ago that machine tools are an investment. You can use them for years and still normally get your money back, or even more sometimes. I have a Taig, but seldom use it because I have a Hardinge turret lathe converted to 220 volts that is just way better. I ran them for decades at work. Then there was this hot chick at work that ran one. She just made my breakfast.

aspeed wrote:Then there was this hot chick at work that ran one. She just made my breakfast.

You married her?