Hempel KA-6 "cockpit"

[LRFitch]

Jim, Rick,
Today I will remove the Smart Fly boards and receiver and see what I can find. With the two boards in the nose, getting them out will not be simple. I can't imagine corrosion of copper being at the heart of the problem. Our average relative humidity runs around 12%, and Tucson's is about the same. We will see.

[ARUP]

Humidity isn't the problem... it's the drooling over the new bird! lol

[LRFitch]

ARUP, No drooling on my part, at least not yet. At first I was a bit terrified that the glider was intact and not banged up from the shipment, and damaged crate. That has gone to "hangover" like state because I can't get it to function properly.
NEW QUESTION--- The info sheet that comes with the new Futaba S-9156 servos states "Ni-Cd use only" but the specs for the speed and torque are rated at 6.0V. I can't recall ever seeing something like this on any servo. Ofcourse, I'm not using NiCds, but instead two 7.4V 5200mah Fromeco LiIon batteries, regulated by a Smart Fly Turbo regulator. Anyone know what Futaba is concerned about?

[LRFitch]

Well, my wife and I have been relaxing on the Oregon coast for the last several days. Mr Hempel has sent a new set of aileron servo extensions for the KA-6, and I should have them Monday when the mail is delivered (very nice man!). I'll replace the aileron extensions, as well as try the servos plugged directly into the Power Board, and see if they work then. Guys, thanks for the continued help and support.

Larry

[Mark9]

As mentioned earlier some servos (even though they give 6 V specs) are not happy above 6. Do you have a 4 cell Ni-Cd pack of any capacity? If so I would suggest you run a test by plugging the battery directly into the receiver and the suspect servos directly in it as well. By doing that you will eliminate any other possibility, except TX and RX. Do the right side servos work OK? If so an other option is to plug the suspect servos into the other wing's outputs.

Also, looking at the Smart Fly web site they have a download of the PDF instruction manual. It states that as delivered the Turbo Regulator is set to approximately 6.6 V output. The instructions to reset it are somewhat involved and it's best that one reads it and look at the drawing of where/how to perform the procedure. I've attached the link to the page where the PDF file is located below. Just click on the "Downloads" tab and then the "Download" text under the "Link" column to download the file.

I tried to actually attached the PDF file to this, but I could not determine how to do it. It would not accept the link as valid. Maybe one of the guys here can help, but I'm not sure if this site will allow PDF's as attachments. If you would like to PM me I could e-mail you the PDF file.

[LRFitch]

Well, some good news, finally. Bill Hempel sent me new 20ga servo extensions for the ailerons, and I've installed them. In addition, I replaced the Futaba aileron servos with a couple Savox 1230 TGs I had in the parts drawer, and now all works fine. I still need to do a little programming to the Smart Fly EQ10 unit to get the ailerons to operate in appropriate directions. I'm sure Smart Fly's website will lead me to success.

[LRFitch]

Guys, I finally have all the KA-6's control surfaces working correctly. Now I need to check the balance point on the glider. I seem to recall that fully assembled, the CoG should be about 5" behind the leading edge at the wing root. Can anyone share if that is correct, or not??? Our first aerotow event is this coming weekend, and would like to get this thing in the air safely if possible.

Thanks,
Larry Fitch

[Tom]

Guys, I finally have all the KA-6's control surfaces working correctly. Now I need to check the balance point on the glider. I seem to recall that fully assembled, the CoG should be about 5" behind the leading edge at the wing root. Can anyone share if that is correct, or not??? Our first aerotow event is this coming weekend, and would like to get this thing in the air safely if possible.

Thanks,
Larry Fitch

make a rope with a loop on each end and slide it over the main wing joiner tube as you assemble the aircraft......pick it up once the wings are on......the plane should hang slightly nose down with this setup for the first flights.......once you get fanmilar with the plane you can move the CG back slightly if you want......mine is still flying 4 years later set up this way.

[LRFitch]

Tom, Thank you very much!! That is exactly what I was looking for.

Larry

[LRFitch]

Owners of the Hempel 50% KA-6,
Bill Hempel told me that the correct balance for the glider is 6.98" behind the leading edge of the wing at the wing root. My measuring says that 6.98" is right at the front of the large wing tube joiner. He stated to achive this balance, he put 11 pounds of lead shot in the nose. I believe Tom's approach (above) will produce a slightly rearward balance point, which is likely why he is still happy with the glider's performance after four years of flying. Thought I'd share the designer's recommendations.

[ARUP]

Tom is a 'cowboy' and likes to live on the edge! lol

[LRFitch]

ARUP, I have to disagree. I don't think Tom is a "cowboy". I think he has developed a much easier way to safely check the balance on the big glider. The wing tube is 2.0" in diameter. So he is balancing the glider 1" aft of the 6.98" balance point, with the nose pointing down a bit. Sounds like he is very close to achieving the same balance point with little chance of dropping the 48 pound glider. Makes sense to me.

Larry

[ARUP]

I'm just 'goofing' with Tom! Somebody's gotta do it... might as well be me!

[lenb]

Having seen and flown these planes many time, even maidened a couple, the CG that typically is or was called out for was wrong- or the guys balanced it wrong. In both cases the planes I maidened, the planes were tail heavy. Both by almost 5 pounds. Maybe the recommendation had been corrected by Bill, now 5 years later, however I would listen closely to Tom and Erik. They have the most time on these planes out of anyone flying one that I'm aware of.
After the CG gets tamed, its a cool airplane and quite a sight coming in for a landing. Its easy to land it short.