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Hempel 50% BD5 Build

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Hempel 50% BD5 Build

Old 04-28-2014, 04:57 AM
  #26  
BillJ
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Hey guys...been out for a couple days....To answer question....I like the plane...I like it even better now that I put a 370 GYRO on the elevator....Made things way better.... No video yet .....working on it.. Will have it at Joe Nall

Bill
Old 04-28-2014, 07:00 AM
  #27  
sticks-RCU
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BillJ, if possible I would like to call and talk to you about your BD5. Please send me a PM with your contact info and best time to call.

Thanks,
John
Old 07-13-2014, 06:15 AM
  #28  
Capt D
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Bill, Don Heath here. I have one coming, should get it by the end of this month. Where did the CG end up? Can't find any CG info any where.

Thanks, Don
Old 07-27-2014, 04:49 PM
  #29  
warpsflyer
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I will be ordering one soon, but need more info. Do you have the thrust/trim issues figured out? Any other info you think is a need to know before embarking on this build?
Old 07-28-2014, 04:12 AM
  #30  
Capt D
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I would suggest you open the box at the FEDEX office before you sign for it. Mine had some damage to the canopy & vertical stab. Bill is sending a new canopy. I have the wings done. Check the ail & flaps, they have little holes already drilled for the horns. you can't see them under the film. I have the stabs done. They also have marks where to drill, look for them. Ask Bill for construction pics, he has a bunch. They help a lot. I'm putting a K-140G in mine. As far as the thrust problem goes, it looks like all you can do is keep the pipe & the front of the turbine as low as possible so as to have the thrust angle pointing upwards as it leaves the tail. This will push the tail down & get rid of the nose over problem. Mixing up elev with full power also is an option. I will be glad to answer any questions you may have as you progress. Don Heath
Old 07-30-2014, 05:53 AM
  #31  
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Just got a long E from Bill H about the thrust problems. He said on his next one he would lower the turbine 1 -2". The swiss have a 50% BD-5 also. There picture show the turbine way down as compared to the normal rail position on this one. Think I will make 2 wedges to bring the front of the turbine down about 1 1/2". Painted the front inside of the fus white, looks a lot better. I'm putting all the air tanks & valves & bat. way up front. Bill said he added 2 1/2 # of lead up front on his to get the CG right.
Old 01-15-2015, 02:00 PM
  #32  
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Haven't heard anything lately, how is the plane doing? I have one on the way, are there any other items that need to be addressed that you haven't covered yet? One last question, what servos are you using?
Old 01-15-2015, 04:35 PM
  #33  
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Check your pm, and give me a call.
Old 01-17-2015, 02:25 PM
  #34  
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It's been along time, I thought this thread was dead. A long story short. Don;t screw around with lowering the turbine as I did. It went in 20 sec after lift off. Lowering the turbine caused it to rotate all on it's own & went up at about a 40 degree angle. All the down elevator was not enough to get it flying, The end result was a pan cake impact. Turbine & radio ended up OK. It's being rebuilt, although I've lost interest. The CG is where Bill had his. The stab & wing were at 0 degrees. If I had not listened to Bill I still would have a BD-5. Advice , leave the turbine where it's supped to be, & put up with a little nose down at full power. So far no $ return from Bill for his bad advice, don't think I ever will see any.
Old 01-17-2015, 03:02 PM
  #35  
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Ow forgot to mention. The only thing I needed in the rebuild from him was the CF wing tube. After what happened, I thought he would give me one. No, charged $25 for one.
Old 01-18-2015, 05:55 PM
  #36  
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Thanks for the info, I will build it stock.
Old 01-19-2015, 09:51 PM
  #37  
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Make sure you re-glue the wing rib in the fuse and double check all the glue joints just to be safe. I am running Hitech 7955TG servo's on everything, and I set up two servo's for the flying stab positioned on the back bulk head right behind the turbine. Everything else on mine is pretty much stock. I haven't flown my new one yet, now I have to wait until the snow stops flying and things dry out.
Old 02-08-2015, 03:54 PM
  #38  
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Received my kit last week, but haven't started it yet. Did yall re-iron the covering? There are no wrinkles in mine just wondering.
Old 02-08-2015, 04:35 PM
  #39  
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I test flew one of these for a friend… To trim for level flight at about medium power was around 20% down elevator. It just looks odd to have that much down, so we unwisely re-centered it for the second flight… shot up and had to use a ton of down trim again. If you fly it at one throttle setting, it is ok, but then that pesky part about landing comes up…. Reduce or increase throttle and you have a roller coaster. Good times….not.
Old 02-09-2015, 04:36 PM
  #40  
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How are you balancing this plane. Fuel tank full or empty? I noticed that the tank is behind the CG, if you balance it empty when you take off you would be tail heavy, which might account for some of the trim problems encountered. And if you balance it full you would land nose heavy, which might not be too bad. I will look to see if I can slide the tank further forward above the CG. Input anyone?
Old 03-23-2015, 10:26 PM
  #41  
bignuts181
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Glad to find this thread I'd love if possible to see a blow buy blow build on this one. Having had a couple of Bills big planes I'm quite interested, hell I've even thought about making the pusher prop version till I'm happy to try out Turbine power for the first time, figure I can sort the bugs out in the airframe. Buy the sounds of it the gyro on the elevator is definitely the way to overcome the thrust line issues.Look forward to more information..

cheers Rossco,
Old 04-06-2015, 10:27 AM
  #42  
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What control throws are you using? Bill Hempel's photos the CG being at the bolt holes for the wing. Is this what is being used?
Old 05-11-2015, 06:38 PM
  #43  
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I want one.. Subscribed
Old 07-26-2015, 07:17 PM
  #44  
rick hamel
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Default 55% bd

Modeled after the Byron--I increased the rear opening to allow the exhaust tube to tilt down (about 3.5 inches in diameter)--turbine is low in model--flies just fine maintaining the full scale angle
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Old 10-12-2015, 04:45 PM
  #45  
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I have 4 flights on mine, the first two were kinda shaky. It does fly different, but I am very satisfied with the plane. My CG is a little nose heavy at the bolt hole in the fuse. I also moved my tank forward to where it is centered on the CG. If you build as per instructions the whole tank is aft CG.
Old 10-13-2015, 05:40 AM
  #46  
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Any videos?

thanks; hmarmaizmd717
Old 05-03-2017, 07:52 PM
  #47  
clavin
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Does anyone still have a build manual? Or CG instructions.. I have one and I DO NOT like the way it flys....


Thanks
Old 05-04-2017, 04:54 AM
  #48  
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There was no manual provided. The attached setup info came from Bill.
Attached Thumbnails Hempel BD-5J setup.pdf  
Old 05-04-2017, 06:31 PM
  #49  
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Just a word of caution, a friend had the wing tube snap on him during straight and level flight causing a wing to come off resulting in a total loss. I don't think the plane had a dozen flights on it and was never flown hard.
Old 07-06-2017, 06:28 PM
  #50  
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Hi All,

I have almost completed my BD5 but note with a K140 mounted on the rails the elevator pushrods foul against the motor. What have others done or do you have to relocate the elevator servos, advice and pictures would be appreciated.

Also those that have flown did you balance with the tank full??


thanks

Peter

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