Black Horse Pitts
05-27-2012, 12:56 PM
#101
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RE: Black Horse Pitts
CG dead on, done based on the info in this thread earlier. Needs only a bigger 2-blade prop. 21x10 Xoar or 20x10 Graupner. Don't know yet which one. Flies like a charm.
05-28-2012, 03:21 AM
#102
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RE: Black Horse Pitts
Nice flight, congrats on a succesful maiden. Glad your cg worked out well, mine was spot on at the LE of the lower wing. The plane flew neutral in normal flight and inverted.
07-05-2012, 08:48 AM
#106
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RE: Black Horse Pitts
Jeb,
I still have my NIB kit waiting in the wings. A brand-new DLE20 is ready to mount up, and I have all servos, etc. Should be up on the boards as soon as I finish my Giant Aeromaster build.
I guess this kit is no longer available, eh? Makes me glad I snagged this one at the $199 sale price at HP, before they ran out. One of the few astute things I have done in my life.
I still have my NIB kit waiting in the wings. A brand-new DLE20 is ready to mount up, and I have all servos, etc. Should be up on the boards as soon as I finish my Giant Aeromaster build.
I guess this kit is no longer available, eh? Makes me glad I snagged this one at the $199 sale price at HP, before they ran out. One of the few astute things I have done in my life.
07-24-2012, 04:44 AM
#108
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RE: Black Horse Pitts
Have flown mine for about one year, still going strong. Had to replace worn out wheels with rubber ones. I found that glue joints need periodical inspection as they tend to get loose in engine mount and wing saddle areas. Maybe too many full throttle tumbling? This ship is not inspiring relaxed sunday afternoon flying. Definitely my favourite plane!
10-12-2012, 05:11 PM
#109
RE: Black Horse Pitts
Well after about a year of on and off building it's finally flight ready. I've been reading this thread the entire time to try and learn from everyone else's first hand experiences so its time to see if I paid close enough attention. I've added a few of my own details like fly wire, rivets and a acrobatic sighting device. I have a DLE30 power plant and its a beast!! Definitely need a throttle curve on it as someone else suggested because it jumps with the slightest throttle input. CG has been my biggest worry but I have it at the leading edge of the bottom wing. Which from JariV's video and post seems to be perfect. So hopefully when the wind dies down and the rain goes away it will be time for the maiden. Heres a few pics...
10-15-2012, 05:41 PM
#111
RE: Black Horse Pitts
Hey thanks! The fly wires are just some 4-40 rod with some Sullivan fly wire brackets that I soldered together in a V pattern and then bent to the proper angle. Then just used longer bolts for some of the struts and attached them. Still need to do the tail fly wires though. The rivets believe it or not are just made from an aluminum colored monokote trim piece that I used a leather belt hole punch to cut out the perfectly round dots. Then just went blind sticking them on one at a time with an exacto knife. A little time and a lot of patience with scrapping and grinding on a piece of 1/4" aluminum rod for the fly wire braces. Im not very good with scale details but when I get bored I try my best with it. It not show quality but all in all I think it looks pretty good. I read on here somewhere that if it's your favorite plane...dont fly it, thats what this plane is becoming!
03-09-2013, 07:29 PM
#112
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RE: Black Horse Pitts
I have this model bh pitts iarf, i am constructing. will power with a dle20. the cowl looks extra large for the fuse.how do you mount it and keep its shape?
03-10-2013, 07:47 PM
#113
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RE: Black Horse Pitts
trs3243,
I also have the BH Pitts, with a DLE20 engine, and the DLE20 fits inside the cowl like it was made for this airplane. All that sticks out is the very end of the exhaust pipe. Perfect fit!
I installed my cowl with four of the DuBro [link]http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXWDH1&P=7[/link] cowl mounting screws, and was able to center the cowl around the fuselage evenly and with no distortion. The DuBro design features plastic standoffs, that can easily be adjusted to slide right up to the inside surface of the cowl and provide good support. This allows you to attach the cowl independently of the firewall periphery, and provides air gaps on each side for good cooling.
Have fun with yours! I just maidened mine yesterday, and it is a superb airplane in every way! And every bit a Pitts, too. I found I needed to carry a bit of throttle over the threshold, to keep the sink rate in check. It is a tame airplane, though, and will not bite you without giving plenty of warning. What a fun, fun plane. So glad I got one!
I also have the BH Pitts, with a DLE20 engine, and the DLE20 fits inside the cowl like it was made for this airplane. All that sticks out is the very end of the exhaust pipe. Perfect fit!
I installed my cowl with four of the DuBro [link]http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXWDH1&P=7[/link] cowl mounting screws, and was able to center the cowl around the fuselage evenly and with no distortion. The DuBro design features plastic standoffs, that can easily be adjusted to slide right up to the inside surface of the cowl and provide good support. This allows you to attach the cowl independently of the firewall periphery, and provides air gaps on each side for good cooling.
Have fun with yours! I just maidened mine yesterday, and it is a superb airplane in every way! And every bit a Pitts, too. I found I needed to carry a bit of throttle over the threshold, to keep the sink rate in check. It is a tame airplane, though, and will not bite you without giving plenty of warning. What a fun, fun plane. So glad I got one!
03-23-2013, 06:51 PM
#118
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RE: Black Horse Pitts
Thanks for the info about mounting the cowl, it looks fine. I mounted my dle20 today with a throttle servo mounted high in fuse and behind gas tank. where did you set the cg? this is a time consuming A R F. it is not for a newbe at all. i have the experence but i am PICKEY.
03-24-2013, 07:27 PM
#119
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RE: Black Horse Pitts
trs3243,
My CG is right at the leading edge of the bottom wing. At that location, the Pitts is rock-solid stable, and yet requires very little down elevator to sustain inverted flight. I have no reason to move it from this location.
Not a build for a newbie? Yeah, I would agree with that. Having a few other ARFs under your belt is a good prerequisite for this one. As for flying it, I recommend this plane for experienced flyers only! You gotta know how to use rudder on take-off, how to control descent rate with throttle on landing, and you gotta be quick on the sticks with the power wound fully up to max. It is a handful. Not a monster, but very nimble. You definitely want to stay awake and not get distracted while flying it.
BTW, the DLE20 is the PERFECT engine for this little bundle of tricks. Long verticals, giant loops, jump-jet take-offs. I fly at half-throttle most of the time, and only use full throttle for the really big maneuvers. I can't imagine strapping a DLE 30 or bigger onto this stumpy little airframe. I flew my Pitts again today, and the engine is behaving really well, breaking in nicely. Almost time to start tweaking the needles a bit.
My CG is right at the leading edge of the bottom wing. At that location, the Pitts is rock-solid stable, and yet requires very little down elevator to sustain inverted flight. I have no reason to move it from this location.
Not a build for a newbie? Yeah, I would agree with that. Having a few other ARFs under your belt is a good prerequisite for this one. As for flying it, I recommend this plane for experienced flyers only! You gotta know how to use rudder on take-off, how to control descent rate with throttle on landing, and you gotta be quick on the sticks with the power wound fully up to max. It is a handful. Not a monster, but very nimble. You definitely want to stay awake and not get distracted while flying it.
BTW, the DLE20 is the PERFECT engine for this little bundle of tricks. Long verticals, giant loops, jump-jet take-offs. I fly at half-throttle most of the time, and only use full throttle for the really big maneuvers. I can't imagine strapping a DLE 30 or bigger onto this stumpy little airframe. I flew my Pitts again today, and the engine is behaving really well, breaking in nicely. Almost time to start tweaking the needles a bit.
03-24-2013, 11:35 PM
#121
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RE: Black Horse Pitts
Yes, same as the manual, 5.51" from firewall to prop hub. I used the Hangar 9 engine mounts, HAN2033, and with the DLE 20 all the way forward, it worked out perfect.
http://www.horizonhobby.com/products...61-2-2-HAN2033
http://www.horizonhobby.com/products...61-2-2-HAN2033
03-25-2013, 08:51 AM
#125
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RE: Black Horse Pitts
My wings also came out at positive 2 degrees, with the stab set at zero. As long as the wings are parallel, I figure I can counter any decalage by using some down trim. I have noticed no tendency to pitch up during throttle-up, so the expressed decalage must not be excessive.
Interestingly, my elevator trims right at zero degrees to the stab for cruise trim. Don't know what is going on there, but I have no complaints about pitch trim with this airplane. It seems to need virtually no trim adjustments for the entire flight profile, which suits me fine. As I mentioned earlier, it doesn't need more than a touch of down elevator for sustained inverted flight, which indicates to me that the CG is set at the aft end of the envelope, and that the effective decalage (as opposed to the geometric decalage) is minimal. It would be interesting to get a read on the angle of airflow at the stab in level flight.
Interestingly, my elevator trims right at zero degrees to the stab for cruise trim. Don't know what is going on there, but I have no complaints about pitch trim with this airplane. It seems to need virtually no trim adjustments for the entire flight profile, which suits me fine. As I mentioned earlier, it doesn't need more than a touch of down elevator for sustained inverted flight, which indicates to me that the CG is set at the aft end of the envelope, and that the effective decalage (as opposed to the geometric decalage) is minimal. It would be interesting to get a read on the angle of airflow at the stab in level flight.