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-   -   Bob Cat Copy Falcon 120 Jet (http://www.rcuniverse.com/forum/rc-jets-120/5913492-bob-cat-copy-falcon-120-jet.html)

Grumman 07-15-2007 05:38 PM

RE: Bob Cat Copy Falcon 120 Jet
 

Quote:

ORIGINAL: Kevin Greene

Flipping the prop just yields less thrust---Prop still works the same way just less efficiently...You need a reversed pitch prop...

Kevin
Right without changing the rotation...
Thanks,
Mojo

knowcrash 07-15-2007 08:39 PM

RE: Bob Cat Copy Falcon 120 Jet
 
any flight reports yet?

Todd Jackson 07-17-2007 11:11 AM

RE: Bob Cat Copy Falcon 120 Jet
 
Johnny,

Did we fly this weekend????
Todd

BuschBarber 07-18-2007 10:28 PM

RE: Bob Cat Copy Falcon 120 Jet
 
What about a Jetcat P80? That is all I have!!!

Todd Jackson 07-19-2007 03:55 PM

RE: Bob Cat Copy Falcon 120 Jet
 
Thats what I am doing.Todd

MattyC-130 07-21-2007 08:51 AM

RE: Bob Cat Copy Falcon 120 Jet
 
I got one. I already have 2 50 bobcats with Tower 75s and they fly great. I am putting a new JetJoe JJ1400 full auto start on mine.
Other components:
- Robart 712 retracts
- Euro oleo struts
- Trim wheels and brakes
- 2 2200 Lipos one for receiver and one for ecu/pump/starter
- 8 Tower digital high torque MG servos in elv rdrs airls and flaps
- FMA copilot 8 ch fail safe receiver( I use a Polk radio system so need fail safe for turbine cut off)
- Fail safe switch with 6v regulator
some mods so far:
- Nose gear will retract forward (filled hole behind mounting plate
- new blind nuts in tail booms for steel cap bolts trash nylon bolts
- Aluminum turbine mount made out of L brackets
- will use glassed 2 Liter coke bottle for fuel and 4 oz UAT
Will update on build and first fly
Matty

i3dm 07-21-2007 09:41 AM

RE: Bob Cat Copy Falcon 120 Jet
 
Where can i see those trim wheels and brakes online ?

highhorse 07-21-2007 11:40 AM

RE: Bob Cat Copy Falcon 120 Jet
 

Quote:

ORIGINAL: DAVID WILDE

I have built and flown the smaller 46 bobcat with wren 44 gold and i have 5 degrees of down thrust which i will be doing the same to the falcon 120. I believe the bobcat has about 7 degrees of down thrust.The reason for this amount of down thrust is two fold ,one so you don't burn your lovely covering but i suggest you ali tape it and secondly the increased thrust velocity under the flat bottom tailplane if was dead straight increases pressure under the taiplane giving a tail up tendency hence the reason for the down thrust to decrease this pressure and reduce pitching down tendencies.
David Wilde COLCHESTER A1 MODELS UK SELLER OF THESE MODELS
Nope, sorry. Plz no offense but you've got it exactly backwards.

Increased velocity across a surface decreases the pressure, pruducing "lift" on that side of the surface. That's Bernoulli's principle. It's how carburetors work. And sprayguns. And wings.

[link]http://hyperphysics.phy-astr.gsu.edu/hbase/pber.html[/link]

So the high velocity airflow under the stab DECREASES pressure, causing a nose-up pitching moment. The Reaction 54 jet has same issues, fixwd same way.

SinCityJets 07-21-2007 03:08 PM

RE: Bob Cat Copy Falcon 120 Jet
 
Johnny,

You get that thing in the air yet??

swat1 07-21-2007 06:46 PM

RE: Bob Cat Copy Falcon 120 Jet
 
Anyone do an electric one yet?

avicom 07-21-2007 07:41 PM

RE: Bob Cat Copy Falcon 120 Jet
 

Quote:

ORIGINAL: i3dm

Where can i see those trim wheels and brakes online ?
Rigth here: http://s43500.sites99.storefront-hos...m/default.aspx Click on weels and brakes in the left side menu.

Rgs

MattyC-130 07-21-2007 07:43 PM

RE: Bob Cat Copy Falcon 120 Jet
 
Trim wheels and brakes at Great Northern Models
Here is the link:

http://s43500.sites99.storefront-hos...m/default.aspx

Eric Banner 07-22-2007 12:47 PM

RE: Bob Cat Copy Falcon 120 Jet
 
1 Attachment(s)
Hi Guys,

Steve Hart maidened his Falcon today at RAF Honington. All went well. thought you'ed like a few photos...

Eric

Eric Banner 07-22-2007 12:58 PM

RE: Bob Cat Copy Falcon 120 Jet
 
1 Attachment(s)

Second flight of Steve's Falcon was by Keith Whiddett.

Keith will shortly be reviewing a Falcon 120 in RCJI. Get your copy on order!

Pictures from the second flight...

Eric

i3dm 07-22-2007 02:03 PM

RE: Bob Cat Copy Falcon 120 Jet
 
Which engie was Steve using ?

Can you provide more info like:
- which fuel tank flight times ?
- which retracts ?
- which mods has he done ? how is the elevator servo mounted ?

etc etc..any info would be great !

Eric Banner 07-22-2007 02:37 PM

RE: Bob Cat Copy Falcon 120 Jet
 
1 Attachment(s)
Don't have too much info...

Engine is the trusty MW54 Mk3 mounted with 5 deg down-thrust. No burning of the stabiliser occurred. Indeed the stabiliser was completely unmarked. Steve had taken the precaution of covering the lower surface with aluminium tape.

Control movements were as the instructions and were O.K.

Retracts were the supplied Graupner units.

3mm control rods and clevises were used throughout. Kavan pinned hinges were used.

The two elevator servos are mounted as the book but with a standard Y lead - opposite side servo arms are used.

The stall when it eventually came was a very gentle nose drop. The Falcon almost came to a halt before stalling in the 5 to 8 mph headwind.

Very little down was needed for inverted flight.

Both pilots reported that it’s a “*****cat” to fly.

HTH
Eric

Quote:

ORIGINAL: i3dm

Which engie was Steve using ?

Can you provide more info like:
- which fuel tank flight times ?
- which retracts ?
- which mods has he done ? how is the elevator servo mounted ?

etc etc..any info would be great !

Grumman 07-22-2007 02:54 PM

RE: Bob Cat Copy Falcon 120 Jet
 

Thank You for the pictures guys really good shooting, always good to see some great shots. Great photographer like to see some of your video work. I can't wait to get a Falcon 120 I also have the Wren MW54 MKlll... Sound like it handled the job just fine... Looking forward to any new material on the flight...
Thanks Again Guys!!!
Happy Flying!!!
Mojo

MattyC-130 07-22-2007 08:20 PM

RE: Bob Cat Copy Falcon 120 Jet
 
I am building one with a JJ1400.
Eric, what servos did you use?

E.Banner 07-23-2007 02:47 AM

RE: Bob Cat Copy Falcon 120 Jet
 
Hi MattyC-130,

Steve used HS225's on elevators and JR811's on ailerons and flaps.

Eric

Quote:

ORIGINAL: MattyC-130

I am building one with a JJ1400.
Eric, what servos did you use?

jonkoppisch 07-23-2007 09:51 AM

RE: Bob Cat Copy Falcon 120 Jet
 
A good plane to make would be a similar design to the baby boomer. Have one slighty smaller for the ram 500/jj 1200 series, one the same size as the baby boomer, monokote and also a composite version. If nitro could do the composite for $350 then!!!!!!!!!!!!!!!

Grumman 07-23-2007 05:39 PM

RE: Bob Cat Copy Falcon 120 Jet
 
Hello Guys!!! Can you provide the AUW of the ready to fly model please???
Thank You,
Mojo

i3dm 07-23-2007 07:22 PM

RE: Bob Cat Copy Falcon 120 Jet
 
jonkoppisch , dont forget these guys dont make jets, this is after all - a prop plane. :D

So guys, is this the ultimate turbine trainer at about 300$ for an ARF ?

wingart 07-24-2007 01:42 AM

RE: Bob Cat Copy Falcon 120 Jet
 
Hi Guys

Iam Steve Hart, The all up wieght of my falcon was 13 pounds dry.
The fuel tank is 1500cc durobo turned on its side,with a 6oz hopper tank for a air trap.
Flight time with the Wren 54 MK3 is a good 7minuets with go round fuel too spare.
And for the money its fantastic value.Iam very pleased with mine so far.
Will try yoo post some video in the next few days.

Grumman 07-24-2007 03:57 AM

RE: Bob Cat Copy Falcon 120 Jet
 

Quote:

ORIGINAL: wingart

Hi Guys

Iam Steve Hart, The all up wieght of my falcon was 13 pounds dry.
The fuel tank is 1500cc durobo turned on its side,with a 6oz hopper tank for a air trap.
Flight time with the Wren 54 MK3 is a good 7minuets with go round fuel too spare.
And for the money its fantastic value.Iam very pleased with mine so far.
Will try yoo post some video in the next few days.
Thank You Steve for the information sounds great... As far as the landing gear goes I guess I can figure for an up to 18 lbs. model, should be fine...
Thanks Again and Happy Flying... Can't wait to see the video...

wingart 07-24-2007 05:02 PM

RE: Bob Cat Copy Falcon 120 Jet
 
Here is a short video of the Falcon 120 in action on her second flight......................... Hope you enjoy


http://media.putfile.com/Falcon-120-Wren-54

PS Had 7 flights in total now and just gets better all the time !

Regards

Steve Hart


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