Bob Cat Copy Falcon 120 Jet
08-01-2008, 12:38 PM
#1451
RE: Bob Cat Copy Falcon 120 Jet
Mine weighs in at 14.2 lbs dry, I carry about 68 oz of fuel. You can fly it straight up out of sight. I have been flying turbines for about 5 years and have a starfire and had a viper both turbine power. I would say my falcon is as fast as the Viper. I friend also has a falcon with a P80 in it and it is also very fast. George
08-01-2008, 01:00 PM
#1452
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RE: Bob Cat Copy Falcon 120 Jet
Hi quick question what would be the ideal airfoil profile for this?
Closest i got was a NACA 1410 modified to 1.5% camber (im new to this airfoil codes but its the closest i found to my bobcat .50 wing on profili)
Thanks
Closest i got was a NACA 1410 modified to 1.5% camber (im new to this airfoil codes but its the closest i found to my bobcat .50 wing on profili)
Thanks
08-01-2008, 01:48 PM
#1453
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RE: Bob Cat Copy Falcon 120 Jet
ORIGINAL: aquaskiman
Mine weighs in at 14.2 lbs dry, I carry about 68 oz of fuel. You can fly it straight up out of sight. I have been flying turbines for about 5 years and have a starfire and had a viper both turbine power. I would say my falcon is as fast as the Viper. I friend also has a falcon with a P80 in it and it is also very fast. George
Mine weighs in at 14.2 lbs dry, I carry about 68 oz of fuel. You can fly it straight up out of sight. I have been flying turbines for about 5 years and have a starfire and had a viper both turbine power. I would say my falcon is as fast as the Viper. I friend also has a falcon with a P80 in it and it is also very fast. George
08-01-2008, 01:55 PM
#1454
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RE: Bob Cat Copy Falcon 120 Jet
I was thinking the same thing. Everywhere I flew my Kangaroo with 18lbs thrust, people thought it was really fast, and were shocked to hear best it ever did was 178mph out of a very steep dive. 180-200 is pretty darn fast and not likely to happen with a Falcon.
Here's 178mph.
http://www.youtube.com/watch?v=y_kDRDtAqNY
Here's 178mph.
http://www.youtube.com/watch?v=y_kDRDtAqNY
ORIGINAL: noahb
I doubt it is doing 180-200. I have dove mine full power and come out straight and level and was clocked at 168 mph after a 100 or 200 feet. However, anything is possible. The falcon has a thick wing and stab. However, it could be that his engine is putting out more then 14lbs of thrust. Who knows.
I too have the super bee and I have exellent vert. Not on take off, but once up to speed, it will climb very good for awhile. Not unlimited, but very good.
I doubt it is doing 180-200. I have dove mine full power and come out straight and level and was clocked at 168 mph after a 100 or 200 feet. However, anything is possible. The falcon has a thick wing and stab. However, it could be that his engine is putting out more then 14lbs of thrust. Who knows.
I too have the super bee and I have exellent vert. Not on take off, but once up to speed, it will climb very good for awhile. Not unlimited, but very good.
08-02-2008, 11:35 AM
#1457
My Feedback: (6)
RE: Bob Cat Copy Falcon 120 Jet
ORIGINAL: aquaskiman
Mine weighs in at 14.2 lbs dry, I carry about 68 oz of fuel. You can fly it straight up out of sight. I have been flying turbines for about 5 years and have a starfire and had a viper both turbine power. I would say my falcon is as fast as the Viper. I friend also has a falcon with a P80 in it and it is also very fast. George
Mine weighs in at 14.2 lbs dry, I carry about 68 oz of fuel. You can fly it straight up out of sight. I have been flying turbines for about 5 years and have a starfire and had a viper both turbine power. I would say my falcon is as fast as the Viper. I friend also has a falcon with a P80 in it and it is also very fast. George
08-03-2008, 04:56 PM
#1459
RE: Bob Cat Copy Falcon 120 Jet
Mine just flew 3 flights.
Fly`s absolutly great
Unfortunatly, my JJ-1400, which was running realy well, threw a turbine blade. [:@]
Fly`s absolutly great
Unfortunatly, my JJ-1400, which was running realy well, threw a turbine blade. [:@]
08-03-2008, 05:26 PM
#1461
RE: Bob Cat Copy Falcon 120 Jet
Yea...I actualy flew the entire third flight with the blade like that.
There was vibration from idle 45.000 until 50.000 rpm, then it ran smoothe to 160.000. Very strange. But even at full RPM, it had noticable reduced power.
So I landed as soon as i felt something was wrong.
There was vibration from idle 45.000 until 50.000 rpm, then it ran smoothe to 160.000. Very strange. But even at full RPM, it had noticable reduced power.
So I landed as soon as i felt something was wrong.
08-04-2008, 07:05 AM
#1463
RE: Bob Cat Copy Falcon 120 Jet
Thanks George.
The plane realy flys well, so it was not realy an event to get it down safely
Ill try and order a new turbine wheel for it, or buy a MW-54 kit or merlin 90.
The plane realy flys well, so it was not realy an event to get it down safely
Ill try and order a new turbine wheel for it, or buy a MW-54 kit or merlin 90.
08-04-2008, 11:23 AM
#1464
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RE: Bob Cat Copy Falcon 120 Jet
ORIGINAL: SJN
Thanks George.
The plane realy flys well, so it was not realy an event to get it down safely
Ill try and order a new turbine wheel for it, or buy a MW-54 kit or merlin 90.
Thanks George.
The plane realy flys well, so it was not realy an event to get it down safely
Ill try and order a new turbine wheel for it, or buy a MW-54 kit or merlin 90.
get a supersport and feel the power !!!!!!!!!!!!!!!!!!
08-04-2008, 11:42 AM
#1465
RE: Bob Cat Copy Falcon 120 Jet
ahhh...I dont know...
The merlin 90 has more thrust, and is cheaper, and it also comes from a company with a good reputation.
I have ordered a new turbine wheel. The parts in the JJ still look nice, and fit well.
The merlin 90 has more thrust, and is cheaper, and it also comes from a company with a good reputation.
I have ordered a new turbine wheel. The parts in the JJ still look nice, and fit well.
08-04-2008, 11:53 AM
#1466
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RE: Bob Cat Copy Falcon 120 Jet
Wow! You took all that apart by yourself ? It does look very clean. Good luck finding a wheel. Do you perform the re-balance yourself ?
... zak
... zak
08-04-2008, 12:01 PM
#1467
RE: Bob Cat Copy Falcon 120 Jet
lol, its not rocket science.
Buying a JJ, makes you wiser
JJ sells the turbine wheel balanced.
I will install it, and see how it runs. Any sign of imbalance, and I know someone who can help me get it re-balanced.
Buying a JJ, makes you wiser
JJ sells the turbine wheel balanced.
I will install it, and see how it runs. Any sign of imbalance, and I know someone who can help me get it re-balanced.
08-04-2008, 01:30 PM
#1468
RE: Bob Cat Copy Falcon 120 Jet
ORIGINAL: SJN
lol, its not rocket science.
Buying a JJ, makes you wiser
JJ sells the turbine wheel balanced.
I will install it, and see how it runs. Any sign of imbalance, and I know someone who can help me get it re-balanced.
lol, its not rocket science.
Buying a JJ, makes you wiser
JJ sells the turbine wheel balanced.
I will install it, and see how it runs. Any sign of imbalance, and I know someone who can help me get it re-balanced.
I would throw this turbine engine to the bin, or use it as paperweight. You're risking your life, it just isn't worth it. [sm=thumbs_down.gif]
08-04-2008, 06:30 PM
#1471
RE: Bob Cat Copy Falcon 120 Jet
hah...I found an old picture that I took about a year ago.......you can actualy see the fault lines in the blade where it has cracked!
08-04-2008, 11:12 PM
#1472
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RE: Bob Cat Copy Falcon 120 Jet
Yes, I can see the fault lines clearly. That's exactly where it broke. The two to the left of it also appear to be nicked.
It is good that you are replacing it.
... zak
It is good that you are replacing it.
... zak
08-05-2008, 12:36 AM
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RE: Bob Cat Copy Falcon 120 Jet
Well that's kinda unsurprising isn't it?
Just some facts for the numerically inclined:
The roots of the blades experience 250,000G's at top RPM. That turns out to anywhere between 400lbs to over 2000lbs of stress depending on the wheel in question.
The metal is Inconel 718 or 713 and is operated at a temperature close to the theoretical maximum (read - no room for error).
Inconel is hard to work with. It must be vacuum melted and vacuum cast or some of the ingredients will evaporate leaving something that looks like Inconel but is not.
The wheels MUST BE X-RAYED for cracks, bubbles or other defects (remember - no room for error).
Making good wheels turns out to be rather difficult and expensive. If a single wheel in a batch is found to be faulty the entire batch is scrapped.
These engines, though simple in overall design, do require good craftsmanship. This is part of the reason that they are so expensive.
I seriously doubt that JJ x-rays his wheels. I also doubt he handles Inconel properly. I don't doubt that he cuts costs wherever he can.
Just my ranting $0.02
Just some facts for the numerically inclined:
The roots of the blades experience 250,000G's at top RPM. That turns out to anywhere between 400lbs to over 2000lbs of stress depending on the wheel in question.
The metal is Inconel 718 or 713 and is operated at a temperature close to the theoretical maximum (read - no room for error).
Inconel is hard to work with. It must be vacuum melted and vacuum cast or some of the ingredients will evaporate leaving something that looks like Inconel but is not.
The wheels MUST BE X-RAYED for cracks, bubbles or other defects (remember - no room for error).
Making good wheels turns out to be rather difficult and expensive. If a single wheel in a batch is found to be faulty the entire batch is scrapped.
These engines, though simple in overall design, do require good craftsmanship. This is part of the reason that they are so expensive.
I seriously doubt that JJ x-rays his wheels. I also doubt he handles Inconel properly. I don't doubt that he cuts costs wherever he can.
Just my ranting $0.02