ddemarco

Hi dadragon,

I'm currently using 3.3Kg servos (116 ounces) all over. The alternative microservos I MAY use (I'm not saying I will, just that I may), are 2.2Kg (77 ounces), with metallic gears and ball bearings. Following your statement, I understand they would still be a viable option if needed, except for the flaps. That would be good news, as I could replace 5 servos (each currently 46 grams, almost 2 ounces) for microservos, which weight 12.5 grams (half an ounce) each. That would be quite good (165 grams, or almost 6 ounces saved).

Cheers,

ddemarco

I'll think about it, although re-doing thw cowl is a little frightening...

Cheers,

ddemarco

Thank you so much for doing that for me. This is extremely interesting... My fuse is actually lighter than yours, (mine is 5 pounds and 25 ounces), but my wing is SUBSTANTIALLY heavier (more than a pound heavier than yours!) Now that's something.... I'll check out if there's anytning I can do about that.

Cheers,

ddemarco

Thank you John for your kind words. That's reassuring.

Cheers,

ForcesR

Hello Diego, more then likely whymy fuselage weights more than yourfuselageis due to the installation oftheSaitoFG-204 cycle gas engine. It weights more thana 2 cycle glow engine, plus the weight of theelectronic ignition box, plusthe weight of theextra battery for theignitionand analuminum spinner.

Roger

sensei

I was thinking last night, the last Top Flight kit I built was in the mid 60s and it was a Flight Streak, I had a blast with that thing. I have built many airplanes over the years but I have never built a war bird, I am thinking maybe I should build one of these and see just how light I can get it...

Bob

SWOODS8892

I have a pica spitfire with a 88 inch wing. it is fiberglassed on all surfaces, retracts and flaps. My spitfire weights in at 26 pounds and has a os bgx-1 as a power plant. due to the long tail all spitfires are tail heavy. mine has 5.5 pounds of weight in the nose. It flys awesome and is very stable. It is true, landing speed must be kept up. balance it and fly it. have fun

TTRotary

A radical idea, but have you considered converting it to electric. Because if you do, you can load the batteries, motor, speed controller into the cowl, ahead of the firewall. As an example, a Power 90 with 8S 5000 packs. The 8S pack will add 37oz inside the nose and that should solve your problem. I did a World Models 63" spit this way and made CG with no extra ballast on a lighter Power 60 6S build, on a lighter AUW (8.25lb). There are various advantages, including the fact that the CG does not change in flight and the fact that the electric setup will have more power and peformance that the current setup. This takes some creative packaging but it can be done. Just make the bottom of the cowl a large hatch.

Otherwise, I would echo what others have said. Tail -end weight is 5x nose weight fulcrum. So start at the very back and save every ounce. Not sure how many options you have however. Cockpit would probably have to go. I agree that 40oz will be a handful on this size plane, so try to get closer to mid-30s.

Regarding CG, I ALWAYS fly the maiden on any elliptical wing at CG = 25% root chord - no further back than that, no matter what the instructions say. This will take the snap out of the stall.

Landing configuration - Use a lot of flap. There is almost no such thing as too much deflection with split flaps. You will see full-scale using up to 75deg deflection. The split configuration will add lots of lift (up to 180% of wing CL in the flapped section, or 1.4xCL for the total spitfire wing) and lots of drag, getting that landing and stall speed way down. You should also mix 3-5degaileron reflex to full flaps to increase wingtip washout and give you more tip stall cushion. The added drag does not hurt either. These are slippery airframes and it takes a lot to get them slowed down. Finally, keep some power on all the way to the ground and minimize that elevator.

Your plane looks great by the way.

sensei

WOW, I have to be honest, I am way too much of weight freak to do that, I just couldn't deal with adding that much dead weight in an airplane. I build 96" span airplanes under 16 lbs. with DA 50cc in them.

Michel

Hi

It,s not our fault ,.......................... ( just kidding )

john josey

Short nosed WW1 and 2 fighters are the only model aircraft i know of where there is no way round adding a huge amount of dead weight to balance it, I went to great lenths to minimize this with my 1/5 81" spitfire and still had to add a full 2lb's to balance.

Like you, i'm obsessed with building light, but it's just not possible with these fighters.

Although i wouldnt mind seeing a one roll rolling circle with a B25 or something !

Brad330l

My Feedback: (1)

My Yellow Aircraft Spitfire was not tail heavy. I actually had to move my battery packs back to the cockpit after taxi tests and final balance.
That is a very broad statement is all. It depends on the builder and how you plan your build. Of course sometimes you cant get away from it but I bet if two different builders built the same model with their different skills and knowledge there would be a difference in the nose weight added.

Brad

bigtim

My Feedback: (13)

I had to add around 19 oz. of lead to the nose of my TF Spit to get it to balance out right,it was just under 12 lbs ready to fly

Michel

Hi BigTim

19 OZ ,........................ thats a lot . But you are for sure , not the only one to add so much weight .

This is why , I chose the DLE-20 , or at least one of the reasons . 1 ) gas , cheaper on fuel 2 ) better chose of paints , doesn,t need to be glow fuel proof , 3 ) weight , to compensate for the tail heavy fuse . 4 ) cleaner fuel residue .

Down side ,.................. it is a heavy unite , but , if you add , all the front end weight , + the dead weight , I,m sure the lighter unite will be the DLE .

The last item to purchase is muffler , most likely from J-Tec . BUT ,........................ I am in the process of thinking about making my own muffler to fit . I cann,t weld ,......................... but I can fabricate ,... even make the jigs .

Now I,m hoping DLE , will come out with a DLE-20/RA

Following threads on the TF SPIT , especially the balancing of the ship ,.............. I try and keep in touch .


If there was a contest for the lightest , TF 60 size Spit , I,m sure Roger would win . ............ CONGRATULATIONS ( at least of what I,ve read , here and else where , maybe not )

sensei

Building really light and adding 2 or so inches of length to the nose of the Top Flight Spit would make for much lighter/better flying airplane all around. Take a look at these pictures of the Pica Spit, you can clearly see that the firewall is much further away from the leading edge of the wing in the last three pictures versus the first two Top Flight kit pictures and it looks good, so why not take care of the problem at the building level, kitting level on the T/F kit? Just saying...

Bob

Michel

Hi

Have to agree with you Bob . The lighter the easier it is to fly . BTW , very good solution , extending the firewall ( or nose ) .

But than there is " us guys " who land hot . I like a warbird to be heavy ( please don,t exaggerate what I,m saying ) , seems to add to the flying characteristics , with that added weight , like slipping ( if thats what it,s called " .

Nothing fly,s like a Spit .

Michel

dadragon

Most warbirds are tail heavy because of the short noses I dont have a pitts or ever built one but the war stuff I do build is big 10 ft or bigger so I machine myown engine mts witch weigh up to 6lb if needed so insted of adding alot of lead I build the weight into the bird.just a thaught.

Michel

Hi

It,s still dead weight ,....

Michel

alanc

use a closed loop.i think you guy call it pull pull on the rudder, this loses a pushrod, get the servos up front as far as possible, get a brass flywheel turned up, no bigger than 30mm, as long as is needed, i do this on my YT/ASM birds, and mine are always lighter than the rest, a guy in our club flys one of the TF spits on electric, and its over 12 lb, AND it has a full sound system, its easily the best representive of a spitfire in the air i have ever seen, it looks more convincing than my YT MK14, and thats saying something, over here, Richard Rawle flys a 1/3rd MK9, home designed (and availableas a kit) it has 11lbs strapped across the mounts, there is no solution, if its a spit, it will need nose weight, sorry, there is a solution, film the thing, and give it a horrible built up flat plate tail, but that kind of warbird is just a sports model in disguise, find a mate with a lathe, and try it out

sensei

OK, think about this for a minute, if you build very light, especially from the C/G aft and extend the firewall a couple of inches you could conceivably end up with a very light airplane with no lead at all, the airplane will still fly just as fast, will go through a turn faster that it's porky counterpart, possesses a lower stall speed and will slow down real nice when landing. Now here is the kicker, if you want that heavy feel on the sticks and those hot landings you now have the option to place at will as much dead weight right on top of the C/G center mass the fuse, that is the place it belongs if you must. but you can remove it at will too.

Bob

alanc

i have been know to put ballast on the cg of a model, to make it stop blowing around like a butterfly, lightness, and models of fighters dont do it for me, i like the model to have presence

Shaun Evans

Hi,

I'm with you, Alan. I have trainers and sport planes for that butterfly feel. I like my warbirds to fly like heavy metal birds of prey.

Brad330l

My Feedback: (1)

Once at a fly-in many years ago I loaded up one of my trainers with a compartment slung under the belly and kept on loading it up till I had one heavy bird. It was a lot of fun and in the quite windy conditions it behaved itself very well. As I remember a dead stick ended the fun.

Brad

tfarmer96

i put a saito 125 on mine and she flew like a champ. That was my first kit my first warbird and it flew like it was on rails i loved it!!! I did have to put i think 2 lbs on the nose of mine

http://www.youtube.com/watch?v=bH54MtSLqxk

Michel

Hi

Well now ,....................... that makes three of us , they just seem to ride better when there heavy . slightly nose heavy .

Michel