I've picked up my 109, bought the servos and mail ordered the brushless set-up.

I'm going to follow your advice Kelvin and beef up those launch holes, and after trying the motor for size I think I'll follow your example of modding the motor mount area as space is in short supply. I'm gonna pop down the workshop in a while to make a start.

I'm looking forward to seeing the results of your next test flight. I hope all goes well this time round, good luck. 

Hi Andy,

Will you be doing a build blog?

Been out with the 109 this morning, nice day no wind at all so I bottled it .

The 12x8 prop is giving a lot more thrust, but just to be on the safe side I will wait for a bit of a breeze.

May try later today .

This is a video of a successful launch.

Ripmax 109 

and one not so successful

Ripmax 109 2 

Plenty of air under the wheels on these videos Andy

I still suggest that what may be needed is more propellor diameter to increase thrust, coupled with a VERY gradual climb out routine, even allowing the plane to dip a little first if necesssary to help build up flying speed. I have a small ALFA Sabre which I hand launch very easily myself, from a stationary position EG: no run up at all - just a straight and level " determined push". This is an EDF too - far worse than any prop driven model for that sort of behaviour ( excepting of course the lack of torque roll ) with its zero prop wash over the surfaces. It then slowly heads for the ground about 20 feet out, which looks alarming to spectators

( I have heard the hushed gasps behind me )

.....but worries me not one bit - as I know it is now building suitable flying speed.

 As it gets approx 2 - 3 feet from the deck I then very gently apply slight up elevator and watch as she climbs smoothly away into its first climbing turn. Never had a single problem with it in all its flights - now approaching 100.

Plenty of air under the wheels on these videos Andy

I still suggest that what may be needed is more propellor diameter to increase thrust, coupled with a VERY gradual climb out routine, even allowing the plane to dip a little first if necesssary to help build up flying speed. I

I tend to agree with this - I think I could get away with a self launch. I need to really , cos I fly most times just with a mate who now doesn't want to launch it 'cos it crashed last time he did.! And i don't want him to launch it , 'cos although he's a very good mate, he is not a launcher- throws it up like a glider launch.

I figure i could throw it slightly downwards and get to flying speed, but i would like to query the propeller size situation.

If the propeller gets bigger, does it not give better performance at lower throttle , once flying , but less thrust at full throttle , i.e at launch. Would not a smaller prop give more Uumph initially at full throttle.?

I don't know much about this, so I'm thinking aloud here looking for expert reasoning. Timbo

Also, because i have a 72mm prop bar, doesn't my 10 x6 prop blades make for a bigger prop overall?

As I say, I have a 3300 3S battery, a 40 plus controller, so what should i look for on my wattmeter as a maximum watts and Amp draw at full throttle, to give safe but best thrust for take off? I have 11" and a 12" prop blades to try...

TIA

Hi

Just bought myself one these. I've decided to put an Ervine 39 IC engine up front.

Had to rebuild firewall and cut cowl but the final fit is OK. I dont think theres going to be any launch problems, she'l fly right out of my hand untill she breaks the speed of sound.

I,m going to strengthen a few parts like the tail. Can anyone tell me if i need to fuel proof the covering as its designed for electric, I,ve done all the wooden bits that are visible.

I'l let you guys know how she flys.

Nick

Any pictures and/or video Nick?

Dave Rose wrote (see)

Timbo - forum moderator wrote (see)

Plenty of air under the wheels on these videos Andy

I still suggest that what may be needed is more propellor diameter to increase thrust, coupled with a VERY gradual climb out routine, even allowing the plane to dip a little first if necesssary to help build up flying speed. I

I tend to agree with this - I think I could get away with a self launch. I need to really , cos I fly most times just with a mate who now doesn't want to launch it 'cos it crashed last time he did.! And i don't want him to launch it , 'cos although he's a very good mate, he is not a launcher- throws it up like a glider launch.

I figure i could throw it slightly downwards and get to flying speed, but i would like to query the propeller size situation.

If the propeller gets bigger, does it not give better performance at lower throttle , once flying , but less thrust at full throttle , i.e at launch. Would not a smaller prop give more Uumph initially at full throttle.?

I don't know much about this, so I'm thinking aloud here looking for expert reasoning. Timbo

Also, because i have a 72mm prop bar, doesn't my 10 x6 prop blades make for a bigger prop overall?

As I say, I have a 3300 3S battery, a 40 plus controller, so what should i look for on my wattmeter as a maximum watts and Amp draw at full throttle, to give safe but best thrust for take off? I have 11" and a 12" prop blades to try...

TIA

Edit --- I have tried the 10 x 6 prop (on 72mm bar ) on this setup and i get 407 watts drawing 35 amps on full throttle. I reckon this should get me away, and then I'll really cut back on the throttle for flying around. Does this sound Ok , or have i missed something vital?? TIA

There is obviously some compromise to be made when choosing diameter over pitch, and one thing you will notice is that the slower turning large diameter props will provide a higher idle speed IYSWIM. The simplest way to think about the differences is to liken the scenario to a car - large props are like first gear, and large pitch is like top gear.

Now, you wouldn't try to drive off in top gear would you.

As I say, there is a little compromise, and driving off in second gear for instance is a habit of mine regularly executed quite successfully. What do you mean Gordons alive ? - oops sorry got distracted there.....What do you mean "on a 72mm bar " ??

If you get 35A on the 10 x 6 prop, then moving up to the 11" will probably see quite an increase in power.

For instance ....on a setup I am playing with at the moment a 12 x 6 gave me 28A , but moving up to a 13 x 6 showed 37A - over 30% increase.

PS I thought you were getting 311 watts on the 10 x 6 ?

Hi Rocket Ron.

Cheers for the well done, thankyou . 

I try to get out flying at least once a week with my Ripmax Spit.

Hanging  my models  from the ceiling is just to keep them out of the way  of the Kids and the dog not to protect them from my flying , oh and they are a good talking point  with friends and visitors .

I am practising different methods of hand launching with the Spitfire in preperation for the first flight of the 109. No point trashing the 109  if I have not got the Knack of launching it  yet .

I have fitted a bigger prop 12x8 to the 109 waiting for the weather to calm down and for my Wife to be available to film the next attempt .

Having a U/C is better if you have a good  surface to fly from. I chose the Spit and the109, having no U/C they are  ideal for the field (long grass)I fly from .

I like buildind but not as much as flying,this is why I have ARTF's to get a few models flying to keep me going.

I am very tempted to build the Hawker Hurricane from the RCM&E plan due out in october as a winter project .

You should be able to reto-fit retracts to the 109 okay, quite a few  folks have fitted retracts to the Spit with no problems or you could make a take off dolly.

Cheers

Kelvin . 

Kelvin...,Thankyou for taking so much of your time in reply...,no problem,pleasure is mine...,very informative good to read,an artist as well..(Hermen the German)..could it not be a British pilot flying it,with our markings,as may have been nicked,as you do in war time!!.is this not true??.,must agree to SPITFIRE is was more than a good name agree..the clipped wing mk5 dont think available to build..,maybe in blue print build form?..temped to do 109 but feel spit to go for next.