flywise

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Posts posted by flywise


  1. fantastic, I am excited to see/hear your cat in the air. Also I'd love to see your final W&B with the 582 engine fitted....see the difference with my 912 setup. Let me know if I can help you in any way for your 1st flight;)

    P.s :phase 1 radius 500NM?


  2. Regarding engine choices for the catalina...it's all about weight and W&B. The Catalina is fairly tail heavy and the engine is located back of the aircraft's c of g. From my experience using a 912, I would not install anything heavier because you will have to add weight in the nose to fly solo....that means heavier engine + ballast to fly:(

    Lastly the fuselage upper structure was designed for 65Hp and the most powerfull engine installed with dean wilsons blessing was the 912. I would not trust the structure to be strong enough for more horses....if you do I suggest a structural analysis.

    L.


  3. Brilliant chris, keep at it and you will fly her soon:)

     

    One question I have for you: why is your battery located that far back? The catalina is tail heavy and I found that the battery in the nose helps a lot on my Catalina.

     

    L.


  4. Here some pictures of mine. Pictures are from under the rear pax seat and also under copilot seat.seat...

    You can also see one damaged by harder water landing.

    DSC01065.JPG

    DSC01067.JPG

    DSC01072.JPG

    DSC01076.JPG

    DSC01077.JPG

    DSC01079.JPG


  5. Thanks

    If I understand you right I would need to stack the plywood until it fits snug between the tube and the hull?

    Ron

    No, each piece of plywood is supposed to be "standing up" on it's edge. Tomorrow I'll get you some pictures of my Catalina for you.


  6. Hi I acquired an avid Catalina kit that had three previous owners. Left wing is built and the seat backs and bottoms are cut out and bent. I have installed the control linkages and the hull. In the instructions it says to make plywood trapezoids 4 inches by 2 1/2 inches by 1 inch and place between the fuselage at each weld cluster and aluminum tube in bottom of hull. I cannot understand what they mean because they are too thin lying down to come into contact with the fuselage, and if standing on their sides they are to big to go between tubing and hull. Can any one help me out? Thanks

    Ron

    Hey Ron,

    I have/had those on my Catalina and found that the dimensions given in the plans are to be taken with a grain of salt. When you slide the fibreglass shell over the structure the gaps will differ from the plans because of the flexibility of the lower fibreglass structure and maybe a slight misalignment. I think the most important aspect is that the plywood re-enforcements keep the bottom skin from buckling when landing on water because of the extreme pressure on it. Dimension of the pieces just have to allow them to fit nicely without bulging the skin outwards . I had a hard landing once and a couple of the plywood pieces broke. After inspection I found that the the plywood was partially rotten because it was wrapped in fibreglass and moisture got in / stayed there without it being noticed (all is painted over)

    I actually replaced the broken plywood pieces with hard foam insulation material. That way they will never rot, are lightweight, very strong when under pressure and easy to inspect (no fibreglass over them). 

     

    Hope this helps, L.

    P.s on my Catalina most tubes on their entire length are linked to the bottom hull, not just at the cluster locations..


  7. A question for everyone. I am considering a mint condition Avid Model C that has been in heated storage for 15 years. The original builder has flown it and registered it as an amateur built aircraft. (Here in Canada) - I do not know if this is considered a basic ultralight or advanced, or another category on its own. What would be the benefit or disadvantage of amateur built category?

    Thanks

    Amateur built is the best category, no limitation except the fact you can't use it commercially.

    Look at the copa website explaining in details all the differences (basic/advanced/amateur/certified/OM)

     


  8. Hey Justine,

    great project..

    I also am from switzerland/geneva and fled the country because of the overly burdensome and expensive FOCA and EASA. I now live in Canada (close to vancouver) and love the freedom I have with my avid Catalina. If you decide to visit Canada one day please come and visit me for some local flying and fun

    :)

    https://1drv.ms/f/s!AvMw5i-09AkLmyLHNPdIaLSnwTWe

     

    Salutations, Laurent

     


  9. You may try the ORATEX fabric covering system....much easier to do and no painting required

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  10. you might be able to get a little more legroom by making the seat back cushion thinner. Also you can convert the mechanical gear to an electric gear, eliminating the gear lever (like I have on my Catalina) 

    also note that in flight the ailerons need VERY little side to side movement for a big effect. 


  11. I would not touch down on the ocean/salt water any time. I live on the pacific but ALWAYS land on lakes & rivers. It is impossible to keep out the salty water from the bottom of the hull and/or clean it off properly . Also all your wiring-avionics-electric connections will suffer, just look at boats operating in sea water. All of them without exception have corroded terminals and corrosion problems. The spar on the catalina is thin aluminum, the bracket holding the spar pin is steel...if not perfectly insulated you will get galvanic corrosion at the worst place among other problems....

    Your Cat won't live long when operated on salty waters for sure.

    As a side note, a friend who owns a Icon A5 thought it was safe to be on the salt water just had a HUGE repair for corrosion.....


  12. Obviously do not forget to inspect for corrosion especially in the bottom of the hull...


  13. Hey Alicia,

    I have a Catalina with a 912 engine. I would look at the weight of the aircraft (My cat was initially nearly 800Lbs empty before I restored it...). On the Cat weight is bad. Also have a good look at the empty aircraft C of G : it has a tendency to be tail heavy with a 912 making it mandatory to add weight in front for solo flights...weight is the enemy. I can fly without added weight ( I weigh 130Lbs)

    below you have a few pointers to my 912 cat specs...

    Empty weight 752Lbs
    Rate of climb: 1200Ft/min + at gross weight (1200Lbs)
    Vx : 52Mph  Vy : 60  ( these numbers are approximative ...what I am comfortable with)
    cruise speed: 92 Mph
    Stall speed: 38Mph
    Take off from water @ gross : 7-8 seconds
    Take off asphalt @ gross no wind : +- 650ft
     
    Now regarding the flying part / items I found stand out: the ground handling is not easy in windy conditions (+15Kts) as the wing has a large wingspan, has a high lift profile and the landing gear is narrow. Visibility is EXCELLENT like a heli. Cabin space is cozy / on the narrow side with 2 people up front ( I am quite small, 5ft4 - 130Lbs. Works great for me and have taken some 185 Lb pax no problem). This bird has very good handling characteristics on water. 
    On asphalt It is best NOT to have too strong brakes...being a pusher it can nose over. For example doing a high power run with brakes set it will most likely nose over above 4700Rpm even with elevator full nose up. Also for landing I hardly use any brakes...after touch down it slows very quickly with the bigger tires (already slow on landing)
     
    It climbs very well, easy flying, like a cub. The aerodynamics will not let you go beyond 95-100Mph. In the air it handles wind and gusts well as the wings are quite flexible absorbing turbulence. Elevator and rudder are very effective but flaperons are on the slower roll rate side (big wing). Regarding the 'high' mounted pusher configuration, I have hardly any pitch change when applying/cutting power. Also the Cat is perfectly controllable with engine off/ gliding.
     
    Landing on asphalt is the only time you have to pay attention..fly the thing until it's stopped (narrow gear). Dance with your feet to keep it straight . Also too much crosswind is problematic as the wing sponson on the lee side will easily hit/scrape the ground when using the low wing into the wind technique. Also the gear has no shock absorber and will bend/brake if subjected to a hard landing. The power is plenty and the cat has a tendency to correct any potential runway excursions with engine power application...and quickly, it will straighten and leap back into the air and that's a great feature. Rudder authority at low speed is good.
     
    Stalls are a non event, easy to feel and slow to turn/drop. 
     
    That is in a nutshell what I have experienced. Let me know if you have any other questions.

    C of G positions.jpg


  14. Anyone even remotely interested in a Catalina will want to take a serious look at this plane.

    I know Jo personally. He's the real deal. This plane is the real deal. I've watched the progress. Jo is an incredibly capable builder who pays absolute attention to detail. Everything must be "right" or it doesn't happen on his projects.

    Chris

    Have one already...2 don't fit in my garage

     


  15. Hi Flywise,

    Thanks for the information on the Catalina.  Can you take some measurements for me on the positions of the two fury struts from the root end of the spars? (say from the spar pin on the front and bolt on the rear)  Also, some pictures of yours showing the jury struts would be great.

    Thanks!

    Randy

    Hey Randy,

    here the measurements (roughly) going from the spar pin towards the wingtip:

    Spar pin to first Jury strut is 69,5in

    Spar pin to second jury strut is 89in

    Spar pin to strut attachment bolt on spar is 120 1/4in

    Front and rear attachment is the same distance.

    IMG_8385.JPG


  16. Thanks for all the input so far!

    I went to the plane and ran a couple of tests. My engine serial number is 4425382. It looks like the engines with the fretting problem fall in the 5645xxx serial number range.

    The check for fretting is to measure the torque it takes to turn the engine over with one plug removed from all cylinders. If it takes over 150Nm (110ft-lbs) there is a problem. It takes less that 110 ft-lb to turn my engine over with the plugs installed a long as I move slowly through the compression strokes. 110 ft-lb seems like a lot to me but it's what's in the book and my engine takes a lot less that that to turn over so I think I'm good on the possible fretting issue.

    Then I jumped the battery with a real solid 12V and tried to start it and it did not crank much if any faster, and was still kicking back (wanting to suddenly stop) so it looks like the battery is OK. 

    The Battery is an odyssey PC-680, not PC-612. Senior moment. Anyway it is the same battery model I used to start the 0-320 in my magnum. If it is good it has plenty of power.

    So then I thought what if I just ground the ignitions and crank it? If the problem is the ignition firing before TDC grounding the ignitions will eliminate the kick back. So I cranked it with no ignition spark and it STILL cranked slow and kicked back.

    I am convinced it has to be the starter motor. I am going to remove it and see what the heck is going on. It will take a while to get this done, but I will report back with what I find.

    Chris

     

    Hey Chris,

    the kickback is normal when cranking speed is not high/strong enough as the sprag clutch will let go when reaching compression @ TDC


  17. Thanks again Jim.

    I sounds like I would gain much by stretching it.

     

     

    Hey Laverne, I don't think you got the idea right.

    Originally the model "A" fitted with a lightweight 2 smoke can 'just' take 2 underfed adults - no luggage. If you fit the 912 you will have a one seater for a 185 pound adult + a few ounces of luggage....and if you stretch it (added weight) you certainly will have to be super light human and without luggage. Any modification you do (T3tail gear/big tires/hyd brakes/lots of instruments etc) will decrease useful weight too.

    Hope that shines light in the mud...

    2 people like this

  18. Barkes seem good as well, a little cleaning and they should be good to go! (or should we go full Beringer? :huh::P)

    IMG-20210826-WA0004.jpg

    IMG-20210826-WA0005.jpg

    Hey Laurent, I find that it is safer to have less brakes than too much brakes on the Amphibian/catalina. When you come into landing the amphibian touches down soooo slow (34Mph) you usually don't need the brakes to slow her down. When using the brakes to correct bad runway alignment on landing ( or try and save a bad landing) it's best to have less brakes as the avid will swing hard around its vertical axis because the wheelbase is really narrow. Also consider that a hard breaking or full power run with brakes set will lift the tail up in the air and slam the nose onto the ground with good noise, the elevator is not enough to overcome the pitching moment (high thrust line..)

    Hope that helps :)


  19. Hey Laurent, the fibreglass wrapped over the tube used to be for fixing the tube to the bottom of the hull. Over time this can be a problem causing corrosion. I guess this is under the rear seat?

    Actually it is a little bit behind the rear seat but yes, it is probably designed to bind with the bottom of the hull..!

    If I understand the impact location, the hard landing actually crushed the 'step' ( le redan). That must have been a substantial hard landing


  20. Flywise, there is no information in the manual about thrust line. The engine mount that bolts to the engine appears to put the engine at a slight angle with the nose end of the engine down.

    The main issue that  i have now is where to mount the ignition control boxes.

    I have made changes to the engine mount bolts and rubber discs that at least get the engine mounted. My bolts are 3/8, AN6, as called out in the instructions. At least this will all be out in the open for easy inspection on every flight. As I have said before the manual leaves a lot to be desired.

    I have been taking pictures and will make an effort to post some. I think I should start a new subject if I do that. Joe

     

    I will take close-up pictures of my ignition module install. Most important is that they don't get too hot from engine or radiators..I also mounted them on rubber vibration mounts .

    I am surprised there is no info about the angles the engine has to have. My engine has a 1.5deg to the right as viewed from the rear. My catalina has a tendency to turn left (yaw) proportional with power. It flies perfectly straight without power at the same speeds. I did try a tab on the rudder but that did not help