tecnamman

Sam Firstly, I recommend you check the pins for rust/corrosion pitting/metal dags etc. Since your machine is much older than mine, I suspect your pins will be rusted/pitted and not in pristine condition. If rusty, corrosion pitted etc I would remove and dress with a fine sandpaper strip (don’t worry about removing the zinc plating with the sandpaper, it will have long gone by mechanical action of the disc on the pin)…..my pins were ok because the aircraft was virtually new when I went searching for the problem, which as I said previously, occurred shortly after taking delivery. If you do need to remove the pins, deflate the tyre and apply heat to the pins with a paint stripper gun (the pins are Locktited ) before removing. I assume you have fabricated a wheel bearing nut removal tool?? Next, check the disc for flatness. You will need a perfectly flat surface. I have a piece of thick glass stored under the bench I use for such purposes. Use feeler gauges to measure twist/distortion of the disc….if they’re twisted like an old 45 vinyl record that been left out in the sun forget it…no amount of grease will help!! Some distortion is permissible but my guess they’ll be buckled....mine were but only about 5-10 thou. By the way, I’m no engineer but I reckon Tecnam have gone overboard with the lightening cutouts and the result is a disc with very little strength to resist heat distortion….but as I say Sam, I defer to the experts out there for a second opinion. I also have a theory that when the disc heats up due to ‘riding the brakes’ when taxiing on concrete or bitumen ( I don’t know about yours, but mine will just about reach Vr with the engine rpm set at 2000, which is what Rotax recommend to relieve load on the reduction gear box/clutch…. so you are constantly applying the brakes to slow down when taxiing downwind to the start of the runway), the disc ‘grows’, and because of the close tolerance between the disc locator holes and pins, there is a potential for the disc to seize. So as to the lube to use…..I use STA-LUBE by CRC. Its high temperature grease specifically for lubricating the slide pins and any other moving parts subjected to high temperatures on brake systems. It contains moly disulphide, graphite and Teflon. Part No. SL 3301 available at Burson Auto Parts and Repco. I treated mine about May and have not had a reoccurrence of the violent shudder since. From time to time I get a slight shudder when turning with the brakes on… but only very slight. Applications in a straight line are still essentially shudder free. I know one Tecnam owner who has applied the STA-LUBE (from new) and last time we spoke he said no shuddering had occurred. Sam, when you apply the grease make sure you work the disc back and forth on each pin to spread it evenly and then carefully wipe of any excess at the edges…you don’t want any excess grease flicking onto the disc and contaminating the pads. I have not enquired as to the cost of a new pair of discs, but would be interested to know how much it would cost to fit the certified brakes to the non certified models. My opinion is the Tecnam factory needs to ‘come clean’….admit the problem, issue an AD or SB and assist owners. They are letting their agents down badly… they ‘cop the flack’ when it’s not their fault. There seems to be little opportunity for feedback by customers to the factory. Tecnam need all the feedback they can get both positive and negative to continue to develop their products. A page on their website devoted to genuine owner feedback (log in by serial no.) would enhance their standing dramatically. Hope this has helped but if unsuccessful you might have to buy new discs. I heard somewhere that the solid discs off earlier models are better but can’t confirm this….check with Bruce?? Let me know the outcome Sam. Safe landings 24-4575

Hello Sam Glad I could be of some assistance in solving your brake shudder. You know Sam, it absolutely astounds me that no one at Tecnam (Italy) had come up with this simple solution to what is a very widespread and extremely serious problem. At first I thought it was just a problem with my airplane but have since confirmed what I first suspected…other people must be experiencing the same problem because it’s a design engineering problem and not a one off fault…this has been well and truly confirmed from the comments posted by other Tecnam owners and my conversations with other Tecnam devotees at fly ins and aero clubs. I suspect that they (Tecnam) know about the problem because the certified model of the Sierra, for which you pay an extra $40k has a different wheel brake assembly similar to a Cessna [floating caliper on pins with fixed disc]….my background is in auto fleet maintenance but the problem should be obvious to anyone who comes from a mechanical background…I’m no genius!! Tecnam need to rework the design of the brakes to make them work properly…it’s an issue the factory need to own up to and offer a solution for all owners….it’s not good enough to offer facile excuses and ignore the problem and hope it will go away…Tecnam market themselves as being top of the range in the UL market so they need a re engineer on the design and fix the problem…if you bought a new car and every time you put your foot on the brakes the steering wheel shuddered violently…you’d be back like a shot! What disappointed me the most was the response I received from the Tecnam agent in New Zealand…his answer was totally unsatisfactory and left me wondering….but I won’t go there, the Tecnam community is small and we all have to live together, and the local people are great. Hope somebody in the Tecnam hierarchy (outside Australia!) monitors this site!!!!! Cheers Sam Let’s hear from you Tecnam owners out there about your experiences. That way we all learn. Merry xmas, a happy new year and safe landings 24-4575 tecnamman

Hi Sam Try a call to Shepparton Aero Club, Mid Murray Flying School or Horsham Aero Club….they’re all operating P92’s and may be able to give you a few ideas and steer you in the direction of the most appropriate insurer for your needs. David O

The EASA issued an AD for Tecnam Sierra 2002 - JF and P92-J and P92 JS ‘certified in any category’ regarding seat rail stops on 9<SUP>th</SUP> August 2006 (EASA AD NO: 2006-0234)….you’re probably all aware of it by now but in case some have missed it…this was addressed by Tecnam as SB001-CS dated 24 March 2006 (not listed under non uncertified types on Tecnams website)) The RAA have issued AN 230806-1 dated 23/8/06 for the ultra light non-certified fraternity. This problem was pointed out to me before I took delivery and was fixed by installing clevis pins through the rails at the front. I understand that you can now buy a spanner from Tecnam to undo the wheel bearing nut at around $130……I can’t see for the life of me why they just didn’t use a normal hex head ‘half height’ nyloc or similar that you could undo with standard tools…..am I missing the point or could someone enlighten me why??...originally was not available so made up my own ….lot’s a filing practice whilst cursing Tecnam for such an idea! Any comments welcome Safe flying David O

Hi Louise I own a Sierra 2002 but presume your machine has the same battery as mine….should be a Fiamm 6H4P according to the manual. I cannot locate any dealers for Fiamm batteries in Australia on the web. I haven’t measured the battery dimensions myself, but from web research they are listed as: Length 186mm Width 82mm Height 173mm You will need to check these are accurate. The Odyssey PC 680 is almost dimensionally the same (within a few millimeters) and rated at 17 ah @20 hour rate. You will need to check and see if the terminal connectors are compatible. Go to odysseyfactory.com and click on specifications and check it out for yourself……..then click on dealer locator and select Asia/Australia, then Queensland for your nearest dealer. Sorry I can’t help you more…..my machine is less than 12 months old so haven’t had the need! Please keep us informed… and when you find the correct battery let us know!! Thanks Tecnamman

Hello Linda I’m the Tecnam owner who posted a reply to a request from Paul Willets for other Tecnam owners to respond with observations, tips on maintenance etc about their pride and joys. I have a Sierra 2002 and have clocked up about 50 hours in 5 months of ownership…. so I’m not able to give any long term ‘prognoses’ about the Sierras longevity, but I expect many years of trouble free flying after reading about your positive experiences so far over 500 hours! The Sierra is an absolute joy to fly….light and responsive on the stick with an amazing roll rate more akin to an aerobatic aircraft…. and a breeze to trim with the electric trim on the horizontal stabilizer. I used to do aerobatics (many long years ago), and I get the distinct feeling this little lady (mines of the fairer sex) could handle gentle aerobatics quite effortlessly. Of course, I must emphasize that’s only a sense, as we all know that aeros are strictly forboten in RAA a/c. and I have no intention of proving or disproving my intuition. Regarding the brake shudder Linda; this is how I fixed the problem in mine….and it was quite severe even after a couple of hours of operation. Firstly, I have no idea how handy you are with tools (can’t show any genetically inherited male bias here) so I will assume you can do this yourself. Firstly, remove the main wheel spats. Secondly, observe that the discs are of the ‘floating’ type and designed to slide back and forth minutely on the supporting pins of which there are four. The discs needs slide on the pins so they can self align. I found the discs were jammed solid and unable to slide freely, hence causing a strong pulse at very slow speed and a distinct shudder at anything above a fast walking pace. Initially I was thinking the best way to fix this was to remove the wheel (rather difficult if you don’t have the four point pin socket/spanner to undo the wheel bearing I discovered.) Plan B and ‘work’ the discs back and forth on the pins to push the disc pads away. Now sparingly apply high temperature synthetic brake grease like Starlube or equivalent to the pins, working it all the way around. Oh, by the way, it’s much easier if you jack the aircraft and turn the wheel….I have made (turned) up a lifting attachment from green nylon (a mate had it lying around his workshop so very cheap) that fits in the neck of my workshop jack and lifts the a/c off the deck via the correct lifting point. I used a small screwdriver blade and after application of the grease worked the discs back and forth to spread the grease evenly. Now remove any excess with the small blade (important not to leave any excess that could possibly contaminate the discs or the brake pads…..you only need minimal grease to do the job). Refit the spats and lower to floor……..pull the brake handle 3 or 4 times to seat the pads before you taxi off and check for normal feel when you start moving. It worked on mine and should on yours (the late models all have the same brakes irrespective of high/low wing configuration). I have passed this info on to several other Tecnam owners and advised Bruce and the Vic agents of my solution………all I can say is it worked for me and even though you won’t read about it in the Maintenance manual no one I have spoken to has any real problems with what I’ve done from a safety aspect…….and the brakes on the Tecnam, when you get them to work smoothly, are fantastic. Hope this advise is of some help Keep the posts coming you Tecnam owners out there! Cheers David

Hi Paul That a long haul from Redcliffe to Cairns – approx 800 nm up the coast according to Google Earth! I have not been on such an adventure in the Sierra yet but planning to do so after X-mas. One of the Tecnam owners down here is trying to get a social group together for weekend fly aways etc….. In regards to the brakes……if you’re having trouble with shudder try applying STA or similar high temperature synthetic brake grease to the pins that the brake discs are supposed to slide on. Be very sparing in application and ensure disc moves freely on the pins. Carefully remove any excess grease so as not to contaminate the discs or pads. I had a terrible problem with brake shudder almost from day 1. It was so bad that the whole aircraft shuddered quite violently at the slightest application of brake. I rang the Tecnam distributor in New Zealand and his response was to wait until the pads ‘bed in’. I believe other Tecnam owners have experienced this problem, but I can only confirm 1 other instance to date and another on the grape vine. Hopefully when the word spreads about this site other owners will come on board and share their thoughts and insights. Paul, if you are having trouble with shudder could you let me know……..you didn’t say you were but I’m guessing you probably do since you have asked for my fix. I have done approx 30 hours (TT50) since with no more problems. If you have any other issues/problems/fixes would be pleased to hear. Cheers for now Dave O’Dea

Hello Paul I have just discovered this great site – I was saying to the Tecnam agents in Victoria what a great idea it would be if some IT savvy owner could host a discussion site so fellow owners could share their experiences, information, interesting flights, maintenance issues and possible improvements to our pride and joys I took delivery of my new Sierra 2002 on the 29th March 2006 and have accumulated 35 hours to date, most of it around Tyabb Victoria where she’s hangared. Most passengers (including the local CFI) are very impressed with the new ‘toys’ credentials. Comments like” I can’t believe how smooth it is – hardly any vibration or wind noise. Can’t believe it gets off the runway so fast, lands in such a short distance etc”. I get a few probing questions occasionally like:-“How do think it would stand up to the bump and grind of ab initio training and hire – the 152’s are 30 years old and still going strong – this thing looks too light and fragile to stand up to that sort of treatment My answer is I simply don’t know as no airframe life is specified by Tecnam and no one in Aus has had one long enough yet to find out Basair out of Bankstown has 6 certified versions of the Sierra and I guess they will be the first to find out some years down the track Whilst I’m very satisfied overall, there are a few things that need to be addressed by the Tecnam factory. 1) No floor plates behind the seats in the Sierra – if pens, small tems fall out of your flight bag they end up floating around in the fuselage and risk causing interference with the controls. I fixed that one in very short time by fabricating 2 floor plates out of .020" Alclad. Prime with Tempo Zinc Chromate underneath and finish the top with black satin enamel to match the plates under the seats. It’s a fiddly job and be careful not to put any weight on the baggage floor with the sheet metal screws out – it will collapse under the weight of a battery drill…almost. And don’t drill, screw or even scratch the carry through cast spar…not ever. Forming the rear of the plate to the round cross brace means no alteration to the interior side trims - they reaffix over the top of the plate with original securing screw. Record your mod in the log book and if you hire the crown jewel for dollars it must be signed off by a level 2 or LAME. 2) Shuddering brakes…….I’d really like to hear from you Tecnam owners out there if you have experienced this annoying idiosyncrasy and have you fixed the problem??? Good news if you haven’t……..I think I have, and it seems to work o.k.Enough for now or I run out of material for another session. Some photos of the plates if anyone is keen to make the mod……. Dave O tecnamman