joeflyer

My Feedback: (48)

If the linkage is set up as you suggested in post 3964 then it doesn't matter.

We can agree to disagree on this one, Mike. My approach is to use digital servos on flight control surfaces and analogs on everything else. The easy way to check current draw is with an ammeter during set up. However, that can change with a bump or hard landing. I see no advantage to go through the extra expense and risk of digital servos on flaps, speed brakes, steering, or retract & brake switches.

Joe

BaldEagel

I would not use them on anything other that flying surface's, the real problem is blow back, this used to be a big problem on some of the larger petrol airfames until the advent of Digital servo's it used to be quite often that aileron and elevator responce would decrease with speed with Analog servo's, this all but dissapered with Digitals.

Mike

Mitchell-RCU

My Feedback: (49)

I have pro-link in mine, but not the ones for the falcon 120. I'm using a turbine for power so i did not need the ground clearance. I have the 5.5 inch on the mains, and a 4 inch on the nose. I have a about 2 degrees positive incidence when sitting on level ground.

Mitchell

Xairflyer

My Feedback: (1)

As stated before the geometry is important to maximise the torque of your servo and prevent as mike mentioned blow back.
Use all the travel of your servo not only 80% and make sure the distance from your servo shaft to your linkage is shorter than the length at the horn.

Kelly OConnor

I know this is probably a long shot due to mostly turbine builds of this plane, but I'm building a OS 1.60FX Nitro powered Falcon and am wondering if anyone out there has also built a nitro, three bladed falcon and knows the best size to use. I really like the looks of  a 3 blade and they are shorter.  It sure would save me having to order a bunch of props and do bench and flight testing.  I'm using the Dreamworks,  Nitro Planes Falcon 120 Strut Set and want to make sure I have plenty of clearance for the prop.

rusty55125

My Feedback: (6)

Here is a picture of mine with the Dream Works Prolink gear. They are unmodified and work great. Hope this help!

On a different note, did anyone hear what happened to the Falcon 120 that failed at the Desert Jet Storm Meet over the 2-12 weekend? They didn't get into it too much other than mention that a Jet came apart in the air and showed some blurry video of parts falling. Nothing else was mentioned about what caused it. Anyone know more? The link to the video is below, and if you fast forward to 6min20sec you can see the limited video of the part falling.


http://www.youtube.com/watch?v=uiWfB...layer_embedded

Launch Pad McQuack

I heard from one of the guys who was there...in fact he happens to be in the video clip. He simply stated to me that they were flying the airplane to hard. Warned me upon his return home since I fly an Falcon and didn't want to see the same thing happen to mine. Would be interesting to hear from the pilot/ owner or someone as to what he was doing to over stress it and what mods had been done to the aircraft.

Mitchell-RCU

My Feedback: (49)

What are you using for the balance point? Is it 13 inches measured back from the leading edge of the wing at the point where the wing meets the fuselage. If so mine is coming out nose heavy with two 2150 duralites in the nose.

Mitchell

BaldEagel

Not the first time one has failed in mid air, I know its a long thread, but if you go back you will find reports of bent wing tube's eventually reinforced with a dowel inside, and booms pulling away from the wings, the booms need some kind of reinforcing to take the G loads that a jet can put on this joint.

Mike

tim777jet

hi Mike, the plane was designed as a pusher prop design. We fit a jet and fly energetically, but you have to be realistic. I have seen some guys on youtube pulling G, i would never do, the plane stays together. How much strengthening they do I dont know. I saw recently some footage I think from China or the Philipines, where they fly from roads. I think it was '2 falcons racing' , they fly flat out pretty much, dont know what engine they use, but climb after takeoff is impressive, theirs stay together.
I read the JET International magazine. I an Amazed by the reviews of new built kits which cost a fortune. During the build they find leaking rams, useless pipes, they always seem to modify something, then they fly them and a fair few crash, due to structural failure. As I recall, one had a tailplane half (of an all moving tailplane) which wasnt attached inside correctly, Crash, Undercarriage mounting plates seem to too weak. There seems to be so many failings with these exspensive kits which not not exist.
I can build a Falcon in week, I have done it in my hotel room, with minimal tools, these expensive models with high degree of completion also seem to take a long time to build. So all in all, ÂŁ185 well spent for a model, in my book. Just fly sensibly cheers tim

BaldEagel

Hi Tim

As you know, but possibly by the above post don't remember, I have built a number of Falcons myself and know of their origins, the weakest point on the one's I built was the glue, the formers fell out and the UC bearers also just pulled out, I still have the one I modified, but its now in the loft and not flown anymore as I have some more interesting jets to fly.

Mike

jetster81

I generally find my experience with far eastern ARF's a bitter sweet affair but I have to agree with Tim, I think the Falcon (goldcat 54 in my case) is great value for money especially as there are excellent threads like this to point out the pitfalls of design/construction. I have recently bought mine for conversion to an EDF testbed and have given the kit a good inspection before the build and have come up with the usual mods such as beefing up/removal of some formers,boom attachments and retract mounts. I have taken the precaution of getting an aftermarket canopy just in case and think that it is a small price to pay for such a large model with a good flight pedigree.
I thought I was the only one who builds planes in hotel rooms, it beats watching footy in the bar any day!

tim777jet

hey jetster, I live in maidenhead, where do you live, cant pm you, e mail me [email protected]. maybe tie up, cheers tim

rorrock

We've managed to source a supplier for the Falcon-120 in china.. They are not light so shipping via EMS is a killer...
However we have also sources a retract set and some struts as well...
We can also do a package with Trim aircraft Retracts bodies, brakes and wheels..

I've attached pics and prices are going up on the site for anyone who wants one..

Rob

BaldEagel

Rob

As you are sourcing these from China, can you send them direct to the UK? I am sure a few on here would like to know, especially if it can be done without a hefty carridge charge, I asked recently for carridge from the US to the UK and it was more than the kit cost. LOL

Mike

jetster81

Hi Rob, what price are they shipped from China?, they can be had from Colchester A1models in the UK for 205 quid and is exactly the same except for the name?!.

angel18

Quote:

Originally posted by jetster81

Hi Rob, what price Are They shipped from China?, They Can Be Had from Colchester A1models in the UK for 205 quid and is exactly the Same except for the name?!.

I agree with you, and I also want to know what price they are sent from the china

rorrock

They are up on the site now under Turbine Jets->Trainers..
The shipping calculator when you add them to the cart is accurate.

Rob

CrocEnd

Rob got my Falcon120 to lift of today one word FAST with the Rabbit with a full roll at take off going straight up almost turned 180 and bang canopy blew apart, at that time I had not retracted gear up door still open,hit kill switch,MAGIC dead stick landing after that cheer's all round.
Now that retract set you show pic of that's what I am using the best part is the nose gear you turn the trunion around to vertical remount the the nose gear vertical the nose wheel totally hiden when up.

Any boddy got a canopy in ossie please if not will get a couple from Noray if still available.

Cheer's all
Croc....

Mitchell-RCU

My Feedback: (49)

Ok i have no book on this 120. Can anyone tell me me if the balance point is right. I have it marked 13 inches from the leading edge of the wing at the root where the wing meets the fuselage. I'm using a RAM 500 for power and with that cg i am nose heavy by about 4 oz.

Mitchell

gawlevi

My Feedback: (19)

13" is a good starting point and you will have to go from there. I too was approx 3-4 oz. nose heavy and I'm using a PST j600 (14 lb thrust). I added the weight in the booms along the rudders. I have since adjusted my CG to 13 1/8" and I'm getting better results.

rusty55125

My Feedback: (6)

Well I couldn’t take it anymore! I really like the way this jet flew last year and want to keep it flying for a long time. So I decided to just do it and opened up the wings over the weekend. Actually, it wasn’t too bad other than the insufficient glue in some of the joints. I think if you just remove the covering on the bottom wing and re glue some of the joints you should be fine for most flying. The problem is, I know I will be flying it very hard!
I am including some pictures of the process of removing some sheeting and adding some carbon to the spars. These modifications will defiantly improve the strength and allow me to fly it anyway I want. If anyone wants some pictures of certain areas, let me know. I have one wing to do yet, but I can say at this point, the wing I have done is a lot stronger!!

Scott

joeflyer

My Feedback: (48)

That should help a lot. While you're in there I suggest that you also beef up the retract mounts. Lengthening them so that they span 4 ribs with a good piece of hardwood would do the trick.

Joe

BaldEagel

I think the weakest part of the Falcon is the boom attachement, its the boom itself, it relies on the tensile strength of the bolt (plastic supplied) and the glue joint of the plate and T nut into the boom, everyone needs to have a good look at these areas if converting to turbine use.

Mike

EDIT: yep and the retracts, forgot that Joe, been a long time, although loosing the retract bearer does not generally mean a lost airframe, but loosing a boom, Oh dear, or words to that effect.

rusty55125

My Feedback: (6)

Well, after modifying the two wings, I only gained about 5oz total.
Here is what I did!
1) Removed about 1in of sheeting and replaced with 3” bottom, 2”top
2) I put in 1/2"x.007carbon fiber between the spar and sheeting, full length, top/bottom
3) End grain to join the tube to the new spruce tube spar, top and bottom
4) Same carbon on the spruce tube spar, top/bottom
5) Some additional balsa block around the gear mounts.
6) And shear webing from the root to the tip
7) Re glue all joints in the spar.

She is sitting around 15lbs 10oz's with a Jetcat P-70. Definitely worth the effort!!!

Scott