Black Horse Pitts
06-07-2011, 03:59 AM
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Black Horse Pitts
I thought this airplane would generate a lot of interest, but I have not seen much. I have a build thread going on over on RG Groups.
06-07-2011, 06:29 AM
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RE: Black Horse Pitts
Have you flown your pitts yet?
I'm waiting to find out more about her.
I'm very dissapointed at the new pitts and GP discountinuing thiers.
So when I seen yours I started getting excited again
I'm waiting to find out more about her.
I'm very dissapointed at the new pitts and GP discountinuing thiers.
So when I seen yours I started getting excited again
06-07-2011, 06:51 AM
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RE: Black Horse Pitts
No I have not flown yet, still in the assembly stages but getting closer. I still need a receiver battery and receiver to coplete things. Here is a link to the assembly thread.
http://www.rcgroups.com/forums/showthread.php?t=1378167
http://www.rcgroups.com/forums/showthread.php?t=1378167
06-15-2011, 02:38 AM
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RE: Black Horse Pitts
I have not flown the Pitts yet, still in the process of finishing up details. About all that is left to do is add a receiver and balance the plane. Here is where my delimma starts. The plans state the CG is located 70-77mm (2.75591-3.0135 inches) behind the leading edge of the top wing. I just can not believe that this is correct. Took the Pitts to my club meeting Monday and talked to a few of the top pilots in the club. Actually found one with a 1/4 scale Pitts from some ARF company I have never heard of before. Point being here we talked CG. This planes CG is located 6" behind the leading edge of the top wing, or about at the leading edge of the lower wing! Pilot states it flys very well, not to sensitive and slows down to a very comfortable landing speed.
I decided to visit some full scale CG calculations and found the Pitts S1 CG is located somewhere around the leading edge of the lower wing, plus 1" to minus 4.5".
Visited the 1/4 scale Great Planes Christian Eagle information page CG 6 1/8" behind leading edge of top wing. Also spoke with many others about finding the correct CG for this plane and stumbled upon a very simple method of calculating the CG. Tried it first on my friends Pitts that is flying. Worked out to be the exact location he is using. So with all of the information I have accumulated the CG for my Pitts will be just in front of the leading edge of the lower wing. Moving this forward would result in the addition of lead to the nose but more importantly a needlessly (I think) nose heavy model. Based on my research my plane is just a touch nose heavy and if I am correct then a few of these converted to electric that have flown are very nose heavy. I am going to send a e-mail off to Global Hobbies about this before I fly. More to come!
I decided to visit some full scale CG calculations and found the Pitts S1 CG is located somewhere around the leading edge of the lower wing, plus 1" to minus 4.5".
Visited the 1/4 scale Great Planes Christian Eagle information page CG 6 1/8" behind leading edge of top wing. Also spoke with many others about finding the correct CG for this plane and stumbled upon a very simple method of calculating the CG. Tried it first on my friends Pitts that is flying. Worked out to be the exact location he is using. So with all of the information I have accumulated the CG for my Pitts will be just in front of the leading edge of the lower wing. Moving this forward would result in the addition of lead to the nose but more importantly a needlessly (I think) nose heavy model. Based on my research my plane is just a touch nose heavy and if I am correct then a few of these converted to electric that have flown are very nose heavy. I am going to send a e-mail off to Global Hobbies about this before I fly. More to come!
06-15-2011, 03:34 AM
#7
RE: Black Horse Pitts
On my quarter scale Pitts S2B, the one Cermark had at one
time the CG was 1/4" in front of the rear center cabine attachment
point, flew extremely well. Looking forward to a flight review,
great looking plane, might just have to put one on the list to join
my hanger.
Bill D.
time the CG was 1/4" in front of the rear center cabine attachment
point, flew extremely well. Looking forward to a flight review,
great looking plane, might just have to put one on the list to join
my hanger.
Bill D.
06-15-2011, 07:38 AM
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RE: Black Horse Pitts
ORIGINAL: kerwin50
Have you asked those guys that are flying the electric version how it feels.
Have you asked those guys that are flying the electric version how it feels.
The impression I get is that moving the CG rearward is an improvement. They say it flys fast and lands fast and weights are about 13 pounds. I am going to try mine at 5 inches (127mm) and that is about 1" farther forward than I think it should be. My plane tips the scales at 12 pounds without fuel.
06-15-2011, 06:18 PM
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RE: Black Horse Pitts
I put a DLE 20in mine with smoke and it flys great, takeoffs and landings are fun and an adventure but it's a pretty good plane for the money.Oh one other thing the firewall is like crepe paper,it needs some work.
06-16-2011, 03:24 AM
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RE: Black Horse Pitts
ORIGINAL: telejojo
I put a DLE 20in mine with smoke and it flys great, takeoffs and landings are fun and an adventure but it's a pretty good plane for the money.Oh one other thing the firewall is like crepe paper,it needs some work.
I put a DLE 20in mine with smoke and it flys great, takeoffs and landings are fun and an adventure but it's a pretty good plane for the money.Oh one other thing the firewall is like crepe paper,it needs some work.
Can I ask just where your CG is located?
Thanks
07-04-2011, 03:15 AM
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RE: Black Horse Pitts
ORIGINAL: JimmyZep
I just got a new Model Airplane News Sep 11.
It has the BH Pitts on the cover and a review inside and there
website has a video.
Jimmy
I just got a new Model Airplane News Sep 11.
It has the BH Pitts on the cover and a review inside and there
website has a video.
Jimmy
Thanks
07-04-2011, 05:02 AM
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07-06-2011, 12:19 PM
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RE: Black Horse Pitts
Hi everybody,
maidened mine last sunday. Set up as per instruction manual, found control throws to be too short especially on elevator. I'mplanning on moving CG aft up to the limit of lower wing t.e.. I scratch built an 1/4 Pitts S1-Syears ago. I had no idea where the CG was supposed to be. By trial and error (at least one BIG error) I found that balancing on lower wing t.e was good enough for me and flew it quite a long time (currently under repair due to radio failure). BH Pitts is actually 28% scale, mine has a CRRC GP26R up front and has unlimited vertical, normal fligth at 1/3 throttle. Used the included motor mount and that helps to reduce vibrations transmitted to airframe. Had to reinforce the firewall anyway because of poor glue joints.
With a gasser and both battery packs moved as far forward as possible, had to add about 240g of lead to get close (but not match) CG called by manual. I would recommend reinforcing wheel pants: I broke one in my shop and the other at the second flight from a rough grass field.
Ground handling looks very good to me, just a hint of rigth rudder on take off.
Hope above informations can be useful to somebody.
Have good flights!
maidened mine last sunday. Set up as per instruction manual, found control throws to be too short especially on elevator. I'mplanning on moving CG aft up to the limit of lower wing t.e.. I scratch built an 1/4 Pitts S1-Syears ago. I had no idea where the CG was supposed to be. By trial and error (at least one BIG error) I found that balancing on lower wing t.e was good enough for me and flew it quite a long time (currently under repair due to radio failure). BH Pitts is actually 28% scale, mine has a CRRC GP26R up front and has unlimited vertical, normal fligth at 1/3 throttle. Used the included motor mount and that helps to reduce vibrations transmitted to airframe. Had to reinforce the firewall anyway because of poor glue joints.
With a gasser and both battery packs moved as far forward as possible, had to add about 240g of lead to get close (but not match) CG called by manual. I would recommend reinforcing wheel pants: I broke one in my shop and the other at the second flight from a rough grass field.
Ground handling looks very good to me, just a hint of rigth rudder on take off.
Hope above informations can be useful to somebody.
Have good flights!
07-06-2011, 01:09 PM
#20
RE: Black Horse Pitts
ORIGINAL: ado9518
Hi everybody,
maidened mine last sunday. Set up as per instruction manual, found control throws to be too short especially on elevator. I'mplanning on moving CG aft up to the limit of lower wing t.e.. I scratch built an 1/4 Pitts S1-Syears ago. I had no idea where the CG was supposed to be. By trial and error (at least one BIG error) I found that balancing on lower wing t.e was good enough for me and flew it quite a long time (currently under repair due to radio failure). BH Pitts is actually 28% scale, mine has a CRRC GP26R up front and has unlimited vertical, normal fligth at 1/3 throttle. Used the included motor mount and that helps to reduce vibrations transmitted to airframe. Had to reinforce the firewall anyway because of poor glue joints.
With a gasser and both battery packs moved as far forward as possible, had to add about 240g of lead to get close (but not match) CG called by manual. I would recommend reinforcing wheel pants: I broke one in my shop and the other at the second flight from a rough grass field.
Ground handling looks very good to me, just a hint of rigth rudder on take off.
Hope above informations can be useful to somebody.
Have good flights!
Hi everybody,
maidened mine last sunday. Set up as per instruction manual, found control throws to be too short especially on elevator. I'mplanning on moving CG aft up to the limit of lower wing t.e.. I scratch built an 1/4 Pitts S1-Syears ago. I had no idea where the CG was supposed to be. By trial and error (at least one BIG error) I found that balancing on lower wing t.e was good enough for me and flew it quite a long time (currently under repair due to radio failure). BH Pitts is actually 28% scale, mine has a CRRC GP26R up front and has unlimited vertical, normal fligth at 1/3 throttle. Used the included motor mount and that helps to reduce vibrations transmitted to airframe. Had to reinforce the firewall anyway because of poor glue joints.
With a gasser and both battery packs moved as far forward as possible, had to add about 240g of lead to get close (but not match) CG called by manual. I would recommend reinforcing wheel pants: I broke one in my shop and the other at the second flight from a rough grass field.
Ground handling looks very good to me, just a hint of rigth rudder on take off.
Hope above informations can be useful to somebody.
Have good flights!
07-07-2011, 03:16 AM
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RE: Black Horse Pitts
ORIGINAL: ado9518
Hi everybody,
maidened mine last sunday. Set up as per instruction manual, found control throws to be too short especially on elevator. I'mplanning on moving CG aft up to the limit of lower wing t.e.. I scratch built an 1/4 Pitts S1-Syears ago. I had no idea where the CG was supposed to be. By trial and error (at least one BIG error) I found that balancing on lower wing t.e was good enough for me and flew it quite a long time (currently under repair due to radio failure). BH Pitts is actually 28% scale, mine has a CRRC GP26R up front and has unlimited vertical, normal fligth at 1/3 throttle. Used the included motor mount and that helps to reduce vibrations transmitted to airframe. Had to reinforce the firewall anyway because of poor glue joints.
With a gasser and both battery packs moved as far forward as possible, had to add about 240g of lead to get close (but not match) CG called by manual. I would recommend reinforcing wheel pants: I broke one in my shop and the other at the second flight from a rough grass field.
Ground handling looks very good to me, just a hint of rigth rudder on take off.
Hope above informations can be useful to somebody.
Have good flights!
Hi everybody,
maidened mine last sunday. Set up as per instruction manual, found control throws to be too short especially on elevator. I'mplanning on moving CG aft up to the limit of lower wing t.e.. I scratch built an 1/4 Pitts S1-Syears ago. I had no idea where the CG was supposed to be. By trial and error (at least one BIG error) I found that balancing on lower wing t.e was good enough for me and flew it quite a long time (currently under repair due to radio failure). BH Pitts is actually 28% scale, mine has a CRRC GP26R up front and has unlimited vertical, normal fligth at 1/3 throttle. Used the included motor mount and that helps to reduce vibrations transmitted to airframe. Had to reinforce the firewall anyway because of poor glue joints.
With a gasser and both battery packs moved as far forward as possible, had to add about 240g of lead to get close (but not match) CG called by manual. I would recommend reinforcing wheel pants: I broke one in my shop and the other at the second flight from a rough grass field.
Ground handling looks very good to me, just a hint of rigth rudder on take off.
Hope above informations can be useful to somebody.
Have good flights!
Thanks for the report, keep us updated please!
07-07-2011, 06:43 AM
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RE: Black Horse Pitts
Yes, you are rigth, I meant Leading Edge and NOT t.e. of the lower wing. I you want to be secure balace somewere between lower l.e. and what is recommended by manual and see how it feels. Mine balances about 8mm aft of the point recommended and the plane is very stable, Iwould say too much stable for this kind of plane. Also inverted fligth requires lots of down stick.
To kerwin50
motor is CRRC GP26R, just another inexpensive chinese motor with rear carburetor. I don't know how good it will be on the long run, but for now it has lots of power and never lost a beat. I soldered an aluminum home made muffler to fit inside the cowl without cutting anything. At the moment (knock on wood) I am very satisfied with it.
To kerwin50
motor is CRRC GP26R, just another inexpensive chinese motor with rear carburetor. I don't know how good it will be on the long run, but for now it has lots of power and never lost a beat. I soldered an aluminum home made muffler to fit inside the cowl without cutting anything. At the moment (knock on wood) I am very satisfied with it.
07-07-2011, 04:00 PM
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RE: Black Horse Pitts
The impression I get is that moving the CG rearward is an improvement. They say it flys fast and lands fast and weights are about 13 pounds. I am going to try mine at 5 inches (127mm) and that is about 1'' farther forward than I think it should be. My plane tips the scales at 12 pounds without fuel.
[/quote]
What is your concern over the manufactures CG? On every biplane I have ever had, except for the Beechcraft Staggerwing, the CG was always around the leading edge of the lower wing. Moving the CG one inch forward will make for a nose heavy airplane that may run out of elevator authority on landing that could result in landing gear damage.
PS: On the Beechcraft Staggerwing the CG was at the leading edge of the top wing since this airplane had the lower wing in front of the upper wing, (negative stagger).