Bob Cat Copy Falcon 120 Jet
#2728
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RE: Bob Cat Copy Falcon 120 Jet
Had 2 more flights on the Falcon today (retract air pump went flat!! Plan was to have 4 flights) Great grass jet, but is anyone getting board with their Falcon?
Mav
Mav
#2730
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RE: Bob Cat Copy Falcon 120 Jet
They rotate fine.
I have 64 once juice bottle for fuel. I have found that using about 15 degrees of flap on take off makes for a much nicer looking take off. Without flaps, it tends to pop off the ground. if you use flaps it gives it a smoother lift off the ground.
No, I am not board with mine. Its a fun plane and I have been flying it for 2 years now.
Joe L.
I have 64 once juice bottle for fuel. I have found that using about 15 degrees of flap on take off makes for a much nicer looking take off. Without flaps, it tends to pop off the ground. if you use flaps it gives it a smoother lift off the ground.
No, I am not board with mine. Its a fun plane and I have been flying it for 2 years now.
Joe L.
#2731
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RE: Bob Cat Copy Falcon 120 Jet
If you don't have a slight nose up attitude the plane will tend to leap off the pavement. When building one of these make sure that your retract location and strut length are such that the center of the wing leading edge sits slightly higher off the ground than the center of the wing trailing edge. If you put in too much nose up attitude it will tend to bounce on landing.
My wing is about 3/4" higher in front with the model sitting on the ground. This gives a nice smooth take off. There are a couple others in my club that sit slightly lower in the front and they leap off the runway. If your model is already built you could put a spacer under the nose retract, or the easy fix is to use take off flaps as Joe L. suggests.
Joe
My wing is about 3/4" higher in front with the model sitting on the ground. This gives a nice smooth take off. There are a couple others in my club that sit slightly lower in the front and they leap off the runway. If your model is already built you could put a spacer under the nose retract, or the easy fix is to use take off flaps as Joe L. suggests.
Joe
#2737
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RE: Bob Cat Copy Falcon 120 Jet
Center Tank is about 85oz.
New price for set is $130 .........NO FITTINGS.
Center Tank........$70
Wing Tank........$30/each
I will post these in the buy/for sale section in this site !!!
Derrick
New price for set is $130 .........NO FITTINGS.
Center Tank........$70
Wing Tank........$30/each
I will post these in the buy/for sale section in this site !!!
Derrick
#2741
My Feedback: (41)
RE: Bob Cat Copy Falcon 120 Jet
you are a very sharp guy!!the front tube is for rotation of the wing only..not a spar.i put 3/8 ply inside of fuse just around the hole.then i cut and glue the front tube in the wing only.make it just long enough to go through the ply ring dubler.ther is about 1/2 inch clearance at the bottom ,lower corners ,of the tank. you can run fuel lines and wires in this area.. tank weight is 2.3 oz..
#2742
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RE: Bob Cat Copy Falcon 120 Jet
Hey Rapptor!
That sounds like a good idea! but i wouldnt put my money on that being to successfull...bigger tank more "G,s" in the frame...but please i would love to be wrong on this one...so let us know how the flights go...We have seen bent spars right here on this forum so the wing loading must go some where,and with the fuel bowzer you just cramed in there its gonna really load up the frame around the holes....keep us informed of your succes or lack of either way it will be very interseting!
Cheers
Haydn
That sounds like a good idea! but i wouldnt put my money on that being to successfull...bigger tank more "G,s" in the frame...but please i would love to be wrong on this one...so let us know how the flights go...We have seen bent spars right here on this forum so the wing loading must go some where,and with the fuel bowzer you just cramed in there its gonna really load up the frame around the holes....keep us informed of your succes or lack of either way it will be very interseting!
Cheers
Haydn
#2743
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RE: Bob Cat Copy Falcon 120 Jet
Hi guys, Im with jet junkie on this one, I think the front spar is doing its job and adding to the overall strength of the wing, obviously we all have a choice, and I have the front spar passing right through to both wings. Also, just a reminder, some wing spars are too short and do not reach fully into the end ribs of the wing, check both spars before you fly, as this is a serious weak spot. cheers Tim
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RE: Bob Cat Copy Falcon 120 Jet
Just to clarify, with my old kit and the newer one, the kit is suppilied with an Ally front spar and Ally rear spar.
Inside the wing, there is a lightweight paper/fiber guide tube, that guides the spars into the wing only, it has virtally no strength. It is a guide
The newer kit, has the same two spars but has an additional bolt, towards the front of the wing, which clamps the front of the wing to the fuse. The Older kit, only has the one bolt, which you access through the bottom of the fuselarge.
The newer wing is built lighter, and the wing ribs are spaced slightly further out. This means that the front and rear spares, are approx 1 inch too short to reach the outer most wing ribs, they were supposed to meet up with. This is what i found on mine and as I was abroad at the time, with no access to model equipment, I extended both my spars by 1 inch, by using a piece of fiberglass fishing rod inserted inside the ally tube and joined a 1 inch extension at one end. This is extreamly strong.
I have always used a replacement carbon rear spar, I think its around 20 or 22 mm diameter.
With the addition front bolt on the newer wing acting as an anti rotation device, I am sure the manufacturer, would have left the front spar out of the kit, to save money, if they didnt think it was neccessary.
As I said before, if the spars do not reach their end ribs in the wing, there is a serious lack of of strength and also I would never fly without both spars fitted. cheers Tim
Inside the wing, there is a lightweight paper/fiber guide tube, that guides the spars into the wing only, it has virtally no strength. It is a guide
The newer kit, has the same two spars but has an additional bolt, towards the front of the wing, which clamps the front of the wing to the fuse. The Older kit, only has the one bolt, which you access through the bottom of the fuselarge.
The newer wing is built lighter, and the wing ribs are spaced slightly further out. This means that the front and rear spares, are approx 1 inch too short to reach the outer most wing ribs, they were supposed to meet up with. This is what i found on mine and as I was abroad at the time, with no access to model equipment, I extended both my spars by 1 inch, by using a piece of fiberglass fishing rod inserted inside the ally tube and joined a 1 inch extension at one end. This is extreamly strong.
I have always used a replacement carbon rear spar, I think its around 20 or 22 mm diameter.
With the addition front bolt on the newer wing acting as an anti rotation device, I am sure the manufacturer, would have left the front spar out of the kit, to save money, if they didnt think it was neccessary.
As I said before, if the spars do not reach their end ribs in the wing, there is a serious lack of of strength and also I would never fly without both spars fitted. cheers Tim
#2746
My Feedback: (41)
RE: Bob Cat Copy Falcon 120 Jet
the main spar does not fail at the ends.. it fails in the center..mine was also to short..you are missing the point.. when fliyng,the wing loading is more or less spread over the entire wing..its not lifted just at the wing tip.anyway, after taxie, and 2 minutes of flight,its {the fuel tank}the same as the guy who has 3 tanks!!! now you can fly like a ."SPAZ"... so much for extra g"s the front ,so called spar does not even go all the way through the rib it ends at.. its capt off.. spar?????????
#2747
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RE: Bob Cat Copy Falcon 120 Jet
Rapptor, I also cut the front tube so that I could fit a kevlar tank in mine from turbine connections, the same tank that goes in the old kangaroo's. I got over 30 flights on mine and never had a single issue with the spar. If you look back I believe I have pictures of this. Like you stated the front spar is for anti rotation only.
#2748
RE: Bob Cat Copy Falcon 120 Jet
ORIGINAL: RAPPTOR
the main spar does not fail at the ends.. it fails in the center..mine was also to short..you are missing the point.. when fliyng,the wing loading is more or less spread over the entire wing..its not lifted just at the wing tip.anyway, after taxie, and 2 minutes of flight,its {the fuel tank}the same as the guy who has 3 tanks!!! now you can fly like a .''SPAZ''... so much for extra g''s the front ,so called spar does not even go all the way through the rib it ends at.. its capt off.. spar?????????
the main spar does not fail at the ends.. it fails in the center..mine was also to short..you are missing the point.. when fliyng,the wing loading is more or less spread over the entire wing..its not lifted just at the wing tip.anyway, after taxie, and 2 minutes of flight,its {the fuel tank}the same as the guy who has 3 tanks!!! now you can fly like a .''SPAZ''... so much for extra g''s the front ,so called spar does not even go all the way through the rib it ends at.. its capt off.. spar?????????
Taking into account the stories of folded wings admittedly not total failiers and bent main spars, I would suggest that the main spar is reinforced in some manner to help with the increased load that would be placed on this by removal of the continuity of the front spar.
Just a suggestion.
Mike
#2749
My Feedback: (41)
RE: Bob Cat Copy Falcon 120 Jet
[&o]working on this theory,, i would sure think a prop would aso need a spar???cetrafugal forces aside.did you take note ,that most ,if not all ,wing spars do not go to the tip of the wing?? also they get smaller.. even in a non taper wing..remember the term, main arodynamic center??
#2750
RE: Bob Cat Copy Falcon 120 Jet
ORIGINAL: RAPPTOR
[&o]working on this theory,, i would sure think a prop would aso need a spar???cetrafugal forces aside.did you take note ,that most ,if not all ,wing spars do not go to the tip of the wing?? also they get smaller.. even in a non taper wing..remember the term, main arodynamic center??
[&o]working on this theory,, i would sure think a prop would aso need a spar???cetrafugal forces aside.did you take note ,that most ,if not all ,wing spars do not go to the tip of the wing?? also they get smaller.. even in a non taper wing..remember the term, main arodynamic center??
If a wing spar does not go to the tip of the wing, what supports the ribs?
Main areodynamic center Explain what that is please?
Mike