RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

Finished! 17 Days flat! New personal record!

The Flash is finished and ready for the final control throw setup. The maiden is set for this Sunday!

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

What no pictures???:D

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

yeah we want pictures....

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

Yes some pics would be nice

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

Guys, sorry about the pictures...RCU was giving me fits the last few days!

OK, Pictures as requested.

Some information about the Flash:

evoJet Booster 160 installed, soon to be upgraded to a 160VX
JR 12X with all JR servos. 8411's on the stab, 8711's on the flaps, ailerons, and rudder.
Smart Fly EQ10 handles the power distribution and servo driving chores
2S A123 on the Rx (2 each)
4S A123 on the ECU
Tams Smoke system
Dreamworks Pro-Link Gear
Jet tech wing and main tanks
Old school retract valve and UP6 on brakes
Graphics by www.callie-graphics.com

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

New winter project.

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

Nice Dave,

With that 160VX she's gonna scooooot!

I've got a Merlin 160 in mine and I found I needed crow in it to scrub off speed for landing. Go ahead and put some crow in yourself, you'll like it.

PaulD

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

Took her to work tonight to finish up the final rig....snapped some pictures in the hangar!

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

I'm just installing my engine (merlin 160) into my flash, I have fitted the full bypass but to me there really doesn't look like much of a gap around the front of the engine to allow any air to go around the turbine and keep everything cool

Should I just do without the bypass or run it and see it the temps are ok?

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

i ran mine engine exposed.. with 120sx.. was a rocket.. you dont need it....

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

Hello Carl,

I had the same setup with a Wren160, you can forget the bypass, no need at all.
Now I am flying the same bird with a Jetcat P120SX, still no bypass.

I wish you great fun with your Flash.

Alain

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

Mine has a Merlin 160 in it as well. I just used the "top half" of the bypass and left the bottom half and the intake pipe off.

Works very well and you will be stunned at the speed. As said a 120 is lots with these - a 160 is insane.

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

Thanks for the fast replies guys, once I have finished typing this I'll take the bypass out,

I was thinking on turning the merlin down abit for the first couple of flights,

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

Be careful 'detuning' your turbine. The thrust decreases VERY quickly as you reduce the RPM at the high end! We limited my P-70 by 10,000 RPM as I remember at our field at 6500', and it was nearly a disaster. I went to the Jet Cat website later (should have done that first) and found that 114,000 RPM we had about 14 lbs of thrust at sea level (vice rated 17.5 lbs) and much less than that at 6500' in Colorado.
Regards,
Gus

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

not so much an issue with the big blocks....they can cut 10 lbs and still have a rocketship.....

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

Given the choice, I would much rather downsize than de-rate. The big block is nice when you wanna rip around the circuit and mine will visibly accelerate in the verticals even if the speed when I pull up is relatively low.

The downsides though are too much residual thrust and poor throttle response when you're "just cruizing" around the sky at lower throttle settings. Oh ya, and the fuel consumption really limits your flight times.

I would love to go with something like the P100 or a Cheeta. These next gen engines are producing more thrust in a lighter/smaller package and even 22 lbs from the P100 in a built light airframe would be killer.

PaulD

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

I have 95 flights on my Flash which was built light and comes in a little under 22 lbs dry. To date it has been powered by a 19 lb thrust Rabbit and has really been a joy to fly. My main tank is modified with a sump to provide 95 ounces of fuel which gives 8 minutes of flight time with about 20% reserve. The Rabbit just shipped off for the 25 hour inspection and my new Cheetah was just sitting around so why not stick it in the Flash and see what 31 lbs of thrust does.

While I had both turbines out I weighed them and found the Cheetah to be 8 ounces heaver than the Rabbit. I am not quite done with the install but I am thinking I will probably need about 6 ounces of lead in the front to ballance. All of my batteries are allready up there so there isn't much to move around. That should still result in a weight gain of less than a pound which will leave me somewhere around 23 lbs dry. Not sure what the fuel burn will be just yet but am hoping for 6-7 minutes or reasonable flying with a 2 minute reserve. Don't have the wing tank installed so that is always an option if I start having too much fun.

If the weather is decent this weekend I will report back on the outcome.

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

with a 120sx and resonable throttle.. you will get 8 minutes with a fair amount to spare... thats 30lbs.. my friend has the chettah in his eurosport and eats up fuel quick. i think it will be better in the flash due to the lighter aircraft meaning less throttle to fly nice.... i think you will love the 31lb... you can always dial it back a little....pat

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

I got 7 minutes with a P-120, but prob had more to do with flying wide open for most of the flight. My Ultra Flash has a 160sx and i'll set the timer for 6:30.

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

i am building a ultra flash right now with a 120sx.. how do you like it...

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

A cheetah or merlin 140 would be my first choice for an engine, but seeing as I already have the merlin 160 and at the moment selling a used engine in the uk is hard work, I am just going to use it,

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

I just weighed my flash with a Simjet 3000 (30 lbs) and it weighs 23.4 lbs dry.

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

I used to think this was a great flying plane until Ken pulled the Rabbit out and put the Cheetah in. All I can say is wow, the plane went from a real joy to fly to being an absolute blast. Unlimited verticle and cracking the throttle in the middle of a turn is awsome. There just is no replacement for brute horsepower.

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

Hi guys,

Ok I had 3 flights on my flash with Merlin 140. On the third flight the nose dropped about 8 meters of the deck and ran out of elevator and pancacked. Finally got around to fix damage popped wing pylon and ready to try again. I ran 65 mm flap.

Now give me a landing lesson please. How to set up and land a Flash???

Mav

RE: C-ARF Flash Build Thread for All Flash's being built this winter
 

what kind of approuch did you have with the full flap..were you low or high... also where did you have you throttle at.. i like to land a jet like a airliner.. nose slightly up using the throttle as the elevator.. drag it in... i dont like just comeing around the corner on final and chopping the throttle. sounds to me you got behind the curve a little... no air over the elevators.. try a lower flap setting until you get more comforable with landings.. if you have a big runway never hurts to come in with a little more safe airspeed...