FLASH, Mine arrived , along with a JR Lightning and everything LOOKS good. Flash is Navy scheme and will start build process tomorrow. WHMC

My Red/White chequers scheme Flash arrived today!! Very nice!! Pics shortly

Rgds,
Mark
UK Comp-ARF Rep
www.composite-arf.co.uk

Very impressed!

Rgds,
Mark
UK Comp-ARF Rep

you should !
since you are the rep.

ok finished the Flash

fun to do , easy to build.

i measured the weight incl all servo,s ,tanks , landing gear (jet-1A)
i had to put in the turbine + 3 lipo,s

the weight was 6,4 kilo

i think incl the Wren SS , and Wren Argumenter pipe and lipo,s about 8,4 kilo,s
so i must have the lightest Flash around then .
the thrust measured today was about 8,4 kilo,s without the argumenter
i expect to get about 8,5-8,8 kilos, of thrust.

thinks i trew away:

all chrome screws (some snapped in the middle)
thrust pipe (340 gram!!) that was just the inside pipe.

When will the maiden take place?

ha ha ik dacht al dat je zou meekijken , ik denk dat we deze week een afspraak maken om het nog eens te proberen.
zal de rookpomp maar voorlopig thuislaten .

(talking to our testpilot in dutch nothing secret just making a apointment to maiden the flash)

done some small upgrades to the original one.

Total weight now is 8,8 kilo,s with UAT hopper full , 2 x 2000 kokam lipo 1 x 3200 kokam for the turbine
incl Emcotec ,gasbottle , switches , Fake carbon plate etc etc.

sound like a bad german dialect to me..

hehehe..good luck for the maiden..

how are you smoking the canopy?

this time i used Tamiya Smoke PS-31

spray it in layers at the end spray all until wet , keep on moving it around and heat it with a heat gun.
then it will look smooth and real.

we did the maiden yesterday
Perfect flights it had unlimited vertical with the Wren SS .
take of from Gras was less then 100 feet on the first flight.
then on the second flight we used more flaps , but it did the oposite and we needed more then 250ft!
no trimming needed i set the CG at 265MM just in between the recomended settings.
both flights we had 7 minutes on the main tank and still fuel left , we flew about 80% of the time with full throttle.
power:
2 x lipo,s and a emcotec mini 6 as the main power device
1 x taxi run
2 x flights of 7 minutes
i charged 300 mah in each battery

turbine battery :
3 x starts including 2 flights of 7 minutes and cooldown 512 mah in a 3200 mah kokam lipo.
gear worked extremely good and you could see clearly the wheels going backward on all landings and taxing
so it was a good choice.

few remarks:
Knife edge it seems it wants to roll over when in knife edge , anyone has a idea why?

after the flights the UAT was almost empty and 2/3 full of air ,after inspection we found out why:
the flash main fuselage tank is flat on the bottom this way there is at least 500ml just moving around without the fuellclunk is able to pick it up.
now since we have PLENTY of space with the none delivered full duct i will make the main tank to have a round belly.
just behind the end of the intakes. exactly on the middle on the wing.
i am going to redo the maintank by aplying a half circular piece of composite.
this way the fuel will gather a bit more there ,where the clunk can always reach it.
maybe a good idea to C-arf to NOT glue in the intakes so that they can offer a main tank with a round belly for small turbine users
this way they can hold easy 2.5 or 3 liters and one can leave the wing closed or use it as a smoke tank.!
the intakes can be re routed since for wren users they dont need them anyway.

all in all it was a very impressive 2 flights , with very fast rolls possible.
we did not use the recomended settings for landing and flight modes.
just full flaps on landings with 30% turbine power , this way the wren spools up increddible,and you can hold it nose up and let it decent .
it was still very good in turns and did not wanted to drop a wing.
we used the full elevator setting on flights and landings.
we did however used the expo settings.
the pilot Koen Achten (18years old) did things with it , that we all renamed him Ali Achten........
i will post a video later of both events!.

so all in all:

1: with the JC 120 you have about 10.5 kilos dry weight.
so there is almost 2 kilos difference , and that is a lot if you ask me.
also taking in considering that the Behotec gear is lighter then ours...

2: no need to make difficult and trouble secondary fueltanks and save you 114 usd (or use it as a smoke tank).

Have you ever noticed, that when reps fly their jets, everything is perfect. They never have any problems, design faults or suggestions for improvements.
When others fly, the problems begin to surface. All new jets have design issues that can be improved.
Maybe I am just being cynical.

Regards

Jim

it is not really a problem , but knife edge did not worked for us i am sorry.....

i dont think there is a design fault , but why make a tank flat? especialy for us where we need avery drop of it.
i will figure something out today ,that will surely work.
maybe then Jet-tech will make a new kevlar one and reply,s to my emails i have send him to become a rep for the netherlands...[X(]

Jim


Maybe I am just being cynical. YES

No problem with my aeroplane...if there was I would not write about the flight...
Sandor does not say what speed, if you try knife edge slowly it will roll, as the rookie and many other aeroplanes. C of G can make a difference. Who knows mine does not roll when knifedged fast...as my "heavy" version needs to...

Fuel tank-what clunk? As I said it needs a felt clunk...then it will use all the fuel.

Dave

Hi Sandor!

Just a short question to understand: Where do you get the 2kg weight difference between JC 120 and Wren SS? The turbine itself weights 960g, a 120 roughly 1300g. I think ecu and cables, pump and all accessories are same same. That is 350g plus the second tank, I guess if you put a 120 in yours, you might get it wirbiorne with a difference of 500g dry. Not that bad, considering that fuel-consumption on a SS might be close to a detuned 120

David

{action\flamesuit on}

Hello Dave i am sure it is fast enough to do a proper knife edge.
it just wont do it without aplying other moves

as for the tank , please Dave dont consider me a idiot when it comes to picking up fuel,i feel a bit offended.
i mean you really think i would not use one?
C-arf deliveres standard filt fuelcluncks, witch all of them come from tilotson in ireland (where all of them buy them)
i buy more then 500 pieces a year from there....
since the tank is flat it WONT pickup all the fuel , and that is a waste of your time and mine and surely the flashes flight time.
anyway i modified the tank now , and i am sure this WILL work.
as for writing about flights i will write anything good or bad even if i have to be critical about it (also about myself).
its like c-arf makes the best planes in the world?.
all of them are just people with great idea,s , just dont make tanks flat.
i am just sharing my flights and issue,s about it.
even if i would have been a c-arf rep i would still tell about it.
you also told in your first messages you had the same problem , believe me the felt clunk will NOT pick up all the fuel
it will produce less bubbles therefore a more nice fuelflow to the UAT.
if you see the video later you will see why we got so much air in the uat , now i have added another 250ml and the tank is completely oval now.
i am sure it will make the problems go away.

as for the "noice issue" i have never flown such a quiet jet aircraft.

Best regards

Sandor

{flamesuit off}

Hello David

just read Daves message in the beginning , to get the right CG you needs more weight in the nose
i used just 2 small 2000 lipo,s and a 3200 lipo for the turbine.
thrustpipe is half the weight as the original from C-arf.
i did not use any woodpart from C-arf for anything in the fuselage i trew it all away.
i used 2 electronic valves instead
Jetcat ecu,s are 5 times the weight as a Fadec/Digitech ECU
the valves are half the weight
the fuelpump is half the weight.
like i said in the beginning what is the weight without the turbine?
mine was 6,4 kilo,s.
anyway mine weighted 8,8 kilos, dry and that is no exuse it had unlimited vertical.
Daves was 10.2 or something close.
and you must agree with a 8 kilo turbine and a 12 kilo fueled aircraft you cant do vertical....
mine did...........

Sorry, I didn't want to start an argument. I was just making a general observation that virtually every rep maiden flight is perfect, while I & others sometimes have problems.

I like the Flash & if there is a demo one flying at the Jetpower meeting, I may order one when I am there.

Regards

Jim

dont worry about it.
arguments are good for business , however some read them according to their advantage and file a complaint..
i can remeber a time where i was more helpfull , but that wont happen again on a show..
anyway i am sure you can see plenty of them on the jetpower meeting.
ours will be flying also,to promote only our gears and the engine.
then you can make your opinion right?.
anyway with the flash you make a good choice but keep it light.
like me i like to fly of short gras strips and i want a plane that can take a beating.

Tank is finished , and just tryed the fuel flow when its almost empty and the problem has somehow dissapeared...
and got 250ml extra

Sandor

Interesting

Why does the felt clunk not empty the tank even if it is flat, mine drains till there is almost no fuel left.
What clunk line did you use?
Even flat I would expect 90%+ useage unless of course you are wringing the aeroplane out until the last seconds...which with my 10+ minutes I don't have too ;-))

JP will be fun this year with so much to talk about!

Dave

Sandor. Another item to stock.

Regards

Jim

if i am not mistaking dave is that you are using your wingtank as the main tank
this means the fuel from the fuselage tank goes to the wing tank and then to the uat right?
i cant see it other way.
now while you are flying your wingtank acts like a giant uat , this way you will eventualy drain almost all fuel out out of your main tank.
now we as : Slow , noisy , using no felt cluck flyers. use the fuselage tank as the main tank there for more risk on air.
since the uat holds only 125ml it will fill with air (however i also sell a 250ml variant)
when you say almost no fuel left is that like 500 ml?

just try this:
set the model on its gear dissconnect the fuel lines and slowly empty the tank (fuselage ) you will see what happens.

no i dont stock c-arf items to much work..

i do build about 25 a year for customers and i never make anything on the models.
however when it has a issue , it means "dont look at me , i dont rep them"

it is a nice model , fits everywhere , VERY nice pre build
we used 2 days to build the model (and changed our gear in the same time to fit the flash).
fly,s like a charm , very fast , very slow also.