Hi Rob Thanks for your prompt responses and support! Have you a source for the time limited parts for the H-36, specifically the rod end bearings, fuel shut off valve and the landing gear bow brackets? A search for these part numbers on the net does not get any results for me. (Please excuse the poor sentence structure but you get the idea,,,) Has anyone done a YouTube of the 3000 hour inspection? Thanks again Kurt
On Wed, Nov 1, 2023 at 5:32 PM Rob Thompson <[email protected]> wrote: > Attached is the 3000hour inspection schedule. Check that everything is > still current. > > In Australia our Gliding Federation (GFA) manages registrations so to do a > 3000 hourly you need to be a GFA authorised maintainer with a Survey Rating > from them. A GA maintainer can only do the inspection if the aircraft is > registered as a GA aircraft....which very few are. > regards > Rob > > Rob Thompson > 0429 493 828 > > > > On Thu, Nov 2, 2023 at 9:55 AM Kurt Redinbaugh <[email protected]> > wrote: > >> I fly #3660 in Nevada and am coming up on the 3000 hour inspection. I >> have not noticed the aileron issues noted but am concerned because this >> ship is tied down on the ramp with full covers during the summer months >> when we get temperatures over 100 degrees f. Your pictures of the bearing >> issues would be very helpful in determining the condition of the bearings >> in #3660. >> Who can I find that is qualified to perform the 3000 hour inspection? My >> A& P with IA is an instructor at Abaris Training here in Reno and consults >> with all the leading airframe manufacturers worldwide so I am comfortable >> that he understands composites. >> The nearest Limbach service center is in the UK. Who can I use to tear >> down and inspect my engine stateside? >> I did send the prop to Hoffmann for IRAN with satisfaction (expensive!) >> Thank you for your posts-they are always informative. >> Kurt >> >> On Mon, Oct 30, 2023 at 9:49 PM Ian WIlliams <[email protected]> wrote: >> >>> Hi All, >>> >>> I thought you all may be interested in the following >>> >>> >>> >>> 1. We have finally got our replacement prop from Hoffmann (10 mths) >>> and was rather expensive so when I was told a forklift fork had gone thru >>> the box in transit my reaction was rather predictable. Fortunately it was >>> not damaged >>> 2. Before this happened, I had contact with Airmaster props here in >>> New Zealand. They could produce a really nice little constant speed prop >>> (electrically operated) which would be a real plus for the L2000 >>> Dimona”s. >>> However I got a call from the head honcho of NZ CAA airworthiness who >>> totally rejected the idea. (being a type certified aircraft) Hence the >>> Hoffmann prop. However now the Limbach engines no longer have EASA >>> approval, that may change the H36 type certificate to enable “special >>> Category” or even “experimental” so if there is anybody interested in >>> installing an Electric Airmaster prop that will fit on an L2000 Limbach >>> (correct rotation) let me know as I have organised 2 blades (Made by >>> Sensnich). >>> 3. I think the cracked ferrells of the props has been caused by >>> excessive temperature and humidity levels in our uninsulated, shingle >>> floor >>> and wet hangar over a long period of time. So I am thinking of a >>> controlled >>> heated insulated blanket over the prop and engine. Raychem Autotrace >>> heating cable seems a good suggestion or a slightly modified electric >>> blanket. >>> 4. Currently I have almost finished an annual inspection on H36 S/No >>> 3667 ZK-GPH It has been a real mission. I found a turnbuckle fork end >>> of one of the thrust cables under the engine was broken .. and had been >>> so >>> for a long time so was held only by lock wire. Quite strong lock wire I >>> reckon >>> 5. I have ferried it around NZ for subsequent owners and the aileron >>> control was unacceptably stiff, to a point of “sticking” when operated. >>> Making it a really unpleasant little rocket to fly. >>> >>> This H36 was not a Thai one, but was imported to NZ from Italy (tho >>> German registered D-KEBA) in 2010. However it does have the early >>> “aileron push rod in compression when both ailerons are forced upwards. >>> This was a design problem which was corrected with later serial No’s which >>> had the rods in a tension mode. The aileron bell crank for the older >>> Dimona’s is fabricated from tube while the later (tension) bellcranks are >>> made up of flat plate and there is only 3 bearing sets in the wings as >>> opposed to 5. >>> >>> >>> >>> Now for the jucy bit .. >>> >>> We made a detailed inspection of each of the 10 bearing sets (5 per >>> wing) with a small camera and found some of the bearing sets (3 ball >>> bearings pointing inwards on a 3 piece metal “holder”) mounted on wooden >>> mounts ie the control rod passed thru the bearing sets and through a hole >>> in the mount. We found that some bearing sets were not installed dead >>> centre of the mounting bracket hole The over all clearance being about 1 >>> to 2 mm. >>> >>> The upward load on the ailerons of the H36 when doing say 90 Kts is >>> REALLY high. And I think is underestimated. Hence the compressive load >>> into the pushrods is also VERY high forcing the rod to bend like a snake. >>> Putting a high lateral load to each bearing set. >>> >>> So with misaligned bearing sets some of the bearings were not touching >>> the rod hence “rubbing” on the wooden bearing set mounts. So that is why >>> the ailerons were really stiff in flight but seemed OK on the ground >>> >>> >>> >>> To repair was a mission. We didn’t want to put holes in the wing so >>> designed a cutter system which we made from a short length of brass >>> turned it down to 18mm, put an 8mm thread in one end, rounded off the other >>> end and drilled a hole thru the thing used a 6mm drill cut off and a >>> cutting edge ground so it protruded from the brass”slug” about 3 -4 mm. >>> we then used an old push rod with the “slug” on one end and a battery drill >>> at the other and with great care, removed the mounting bracket material as >>> close as possible to the metal bearing fittings. >>> >>> >>> >>> So it still needs a test flight but problem solved. I think Hoffmann >>> has issues because prior to changing the push rod configuration, there were >>> about 5 different variations of bearing sets in the wings. >>> >>> >>> >>> If any of you want to see some pictures of the procedure let me know. >>> >>> >>> >>> Our Dimona (ex Thai) bearing sets had a solid nylon outer including the >>> outer ball race, so we had no choice than to make big holes and replace >>> them. As they all were seized Another Ex Thai (currently being restored) >>> didn’t have ball type bearings, just Teflon (or nylon rings) S/no 3667 >>> fortunately had proper bearings (ie with a metal outside ball race) and a >>> nylon “tyre” against the push rod. >>> >>> >>> >>> So I thought you all may be interested. I am astounded that the >>> aircraft has been flying for over 40 years like this and would be >>> interested in your comments >>> >>> >>> >>> Best regards >>> >>> >>> >>> Ian Williams >>> >>> Drury >>> >>> Auckland >>> >>> New Zealand >>> >> > --------------------------------------------------------------------- > You are subscribed to the Dimona Owners Group mailing list. > This list is archived in public. http://waikeriegliding.com/dog/ > To unsubscribe, send email to: [email protected]
