flywise

Hey Lenni,

you should get my small contribution through paypal (reginetran) under my wife's name 

BEAUTIFUL Bird....

Hi guys, I have the 912 UL / 80Hp fitted with the Xtra Kit (other pistons increasing compression to 11:1). The Xtra kit manufacturer claims 95 Hp.....

http://www.craftworks.biz/pistonsite/912sales.htm

Cheeers

Hi guys.....at last I have been able to take-off..it's funny but since I got the prop it has been terrible weather (snow, storm, showers etc..), it was hard to wait.

So here my first flights using the Lugaprop/Koolprop in the 3 bladed and 2 bladed configuration (same diameter/69in). On the day of the flight I have not been able (not enough time) to fine tune the pitch for best performance and hence the actual figures are not comparable. Below are my first impressions for you after one flight with each setup..

In favour of the 3 bladed prop:

More t/o thrust (water t/o in 6 secs),

slightly smoother and for some..sexy look

In favour of the 2 bladed prop:

different nicer noise in flight (lower pitch sound) ..remember I have a pusher configuration with exhaust gasses going through the prop,

easier engine start (and starter motor turns faster),

low idle smoother (less/no chatter of the gears below 1800Rpm),

quicker engine response when going from idle to full power,

much lighter (2.5 vs 4.4 Kg) with less moment of inertia (2800 vs 4500)..

The fixed pitch Lugaprop compared to my IFA warp drive is able to provide as good t/o performance and even better cruise speed. I must say that my 2 bladed Warp drive was not able to absorb all the power as it was designed for 80Hp, not for 95Hp....

Next time I will have the data to compare the props more scientifically.

Cheeeers

Personally I would NOT leave the avid flyer tied down outside in the elements. I'd try and have the avid stored inside (ideally have it in your garage at home=0$). Also, you should do the annual yourself. You'll save lots of money and know your bird inside out...

An annual, done by yourself should not cost more that 200-300$. Insurance @ 2K a year seems too high...have you requested a quote?

I operate my avid @ 700$ fixed cost per year. I fly 50Hrs so per Hr including fuel is about 45$....

Also when you rent you have to consider yearly membership fees and the limited availability. You probably will finish your PPL much quicker with your own aircraft hiring an instructor and that is a money saver.

My 2 cents...happy flying

Hey, is this Oratex cloth?? How do you like it??

I believe that the overall prop diameter on some propeller models is adjusted by having different shape / size prop hubs, the blades remain the same.....I do not have proof of this though, to be taken with a grain of salt.

Love mysteries

Hey Fred...Hurrah

I just found that the 101.6mm makes reference to the rotax 912 propeller flange bolt pattern (the outer bolt pattern with the pressed drive lugs).........

Funny my propeller makes me remove the drive lugs and uses the inner propeller flange bolt pattern (without lugs) at 75mm..

Hope that helps

Hey Fred,

I have been measuring everywhere on the hub to find where this   "with a hub with mounting slots at 101.6 mm" could be. I can't find anything close to that measurement. First I thougt that 'mounting slots' means the slots where the blade shank fits into...but no.

Sorry, can't help on this one......

Hey guys, today I received my propeller from airtrikes....here the pictures for you. The quality is very nice/excellent. I had a small damage on my spinner as it was in the box sitting on it's nose....no big deal to repair. I am saving 6.2 Lbs weight changing from my GSC to the L106 Luga (2 bladed setup / weight is 5.5Lbs)....of course I'll have a KIS fixed pitch instead of my in flight variable...

Next I will setup the 3 blade..

Interestingly on the blade it says 1770, I ordered 1750 and it measures exactly 175 cm / 69in

Next step TESTING......wahoooooo it's really christmas for me

P.s just got the 3 bladed together....weight is 8Lbs (vs 5.5 Lbs 2 bladed) and diameter is confirmed at 175 cm (same as 2 bladed)

I have been using PR1750 sealant on B-737 integral fuel tanks and this stuff is very tacky/sticky when applied. The major downside is the toxicity of the stuff. It is horrible to use. You absolutely have to avoid getting it on your skin or breathing in the strong fumes (which is hard to do). When I had to use this sealant I had a breathing apparatus (pressurized mask with fresh air supply) and even then I could smell the PR 1750......

 Also when you use the PR sealant for structural repair or construction it is IMPOSSIBLE to unglue....this is a crazy strong adhesive. 

My 2cents

P.s there is a lot of write up in french in the post and I don't have time to translate it all (yes I am fluent in french) but the guy using the PR1750 sealant says that in the end he would have rather tried / used RESTOM product ( https://restom.net/traitements-reservoir/157-restomkit-poly-1224489129.html?search_query=reservoir+fibre+&results=1 ) instead because of the high toxicity of the PR1750 even though he used gloves and mask...

I like this picture of an aerodynamic analysis of a full scale propeller blade. Nice to see where the vortex is generated visually...

This guy is a great resource for modifications on our birds. He is an amazing professional aerial photographer/video maker (aircraft & drone). Excellent pilot toooo. I highly suggest you watch his other youtube videos......makes me feel so small, it's humbling (I am still trying to make a shake free video after 2 years of trials).

Enjoy, cheeeers

Hello,

I have found a chap who tested 2 bladed vs 3 bladed carbon fibre props for multicopter RC models.....I know this might sound stupid but remember most aircrafts have been a model before being a full size aircraft (wind tunnel testing etc)..  

The great advantage with this test is that he uses the same engine (electric brushless type) and the same propeller pitch/size for each test. It's also more precise/easy to measure electric current consumption vs thrust to determine efficiency instead of fuel flow vs thrust.

The results are in the beginning, so no need to go through all of the video. ......the winner is....2 bladed for efficiency and 3 bladed for thrust (not by much though +7%)

and here another one , not as scientific just comparing 2 vs 3 blade ..... interesting to see the 3 blade prop not so good in cruise above 70% pwr...

I like the Warp drive prop speed calculator but I find it impossible to choose a prop by just looking at the prop tip speed. Different propeller blade profiles/shapes allow for much higher prop tip speeds without loosing efficiency (scimitar for example).  I also think that a prop fitted to a 2 smoke is going to be different than for a 4 banger (very different torque curves).

I would love to see a "calculator" taking into account... engine type/Hp/aircraft speed range/pusher or tractor/ prop clearance/ weight etc..   You just type in the fields and voila.....your best suited propeller comes out with a link to the best distributor closest to where you live

Hey again,

this propeller choice topic I believe is very complex. I am by no means an expert but I will share what / the way I understand this. Please do chime in if I am on the wrong path looking through thick mug........

You have to throw in one more important variable......reduction ratio of your engine (if you have one)!!, the higher the reduction ratio (2.47 vs 2.27 for example), the slower your prop turns which allows you to run a bigger diameter propeller (prop tip speed stays subsonic). A bigger diameter propeller is more efficient and provides more thrust. This obviously has it's limits as you will need the Hp & torque to do that ( for example if you take a rotax 912 80Hp with a 2.27 reduction, there is no point fitting much higher reduction gear and a big Dia. prop as the power would be lacking... 

Now if you take my engine as an example....I have a rotax 912 fitted with the Xtra kit (95Hp) and the original 2.27 ratio reduction. This obliges me to use a smaller prop at higher pitch setting to get the most out of it. Ideally though it would be better to have a 2.47 reduction fitted and use a larger diameter prop at lower pitch setting for best efficiency.

The Item I am a pretty lost is this damn 2 bladed vs 3 bladed issue (why do I see most using 3 blades???)... Now Imagine the same blades, same manufacturer with one setup in 2 blade and another setup in 3 blades....which is better???????  I do not like to compare different propellers/blades makers as you will add another variable there.

If someone is out there and has good knowledge or experience using both I am really interested in having some feedback. 

Cheeeers...

Hey Fred,

the info I have about the c blades vs sc blade shape is that the c blades are able to absorb more Hp as they have  much more cord and blade surface. Look at the difference on the picture.

Gfri

I believe you did very well not to try switching anything....but instead fly and concentrate on landing. Indeed between an engine out at 1000ft and the landing you only have 45 sec to 1 minute to get things working for you. Any trial at starting the engine or troubleshooting would have precluded a good outcome for sure....my 2 cents and thank you for sharing.

Hey Jared,

I am ordering through the Canadian reseller called Vassili    http://www.airtrikes.net/introduction.shtml       as far as I have been able to find out, he buys lugaprops and re-brands them as Koolprop. I don't care and I find it easier this way rather than learn russian or Ukranian and wait a very long time......

My prop, after payment was shipped next day......should be here in about 5 days (canada post still uses donkey's to move across the country)

Hope this helps

P.s what's the price you were quoted? I got 3 scimitar blades (69in), 2 hubs (2 bladed/3bladed), a spinner assembly and the different accessories including shipping and taxes for 1650 usd

I have decided, after many Hrs reading on it, to change from my IFA 2 bladed to a fixed pitch prop/ground adjustable. This decision came for a couple of reasons....first, the inflight adjustable systems are a bit heavier and need more maintenance, have a shorter life. In my case I had a couple of over speeds because of a badly designed / weak bracket on my mechanically adjustable prop control system (from the cockpit to the engine I need a 12 Ft long control cable system). All those "cheap" inflight adjustable props (this excludes the expensive hydraulic constant speed systems using a prop speed governor) will naturally go to full fine in case of failure which will overspeed your expensive rotax 912 engine in a fraction of a second, usually on take off.

The main advantages of inflight adjustable props are to get the best for take off performance and get best speed when cruising (nothing new there).

For my application on the Catalina, the IFA prop has not much/nothing to gain in the top speed range (all I see is manifold pressure increasing....speed not so much), the Catalina being "barn door" aerodynamic with a high lift high drag wing profile. With my IFA prop the T/O is very short at 5800Rpm/fine pitch (at this setting I have to watch like a hawk to not overspeed) but if I coarsen my pitch to 5600Rpm on T/O it hardly makes a difference for me (1/2 - 1 sec more time to get out the water).........hence my decision to shave some weight (~6 Lbs) and keep it simple when I need to be quick on the throttle

The IFA prop is great if you are doing rough field/extreem short field T/O or competition though

I believe I can set the ground adjustable prop for very good take-off performance and not loose much/anything in cruise. .........I will report and confirm this.

Cheeeers

A little update....

as we are nearing christmas I thought I'll get myself an even bigger present....I've been good. Soooo after much debate with Vassili from Koolprop I bought not only the 2 bladed propeller...but I also bought a 3rd blade and I have him send me a loaner 3 blade hub. The thinking here is that I will first set up a 2 bladed version, fly it and then install the 3 bladed version and see if that really makes a difference. If the 2 bladed prop works well (that's what a I prefer) I will send back the 3 bladed hub and keep the 3rd blade as a spare. If the 3 bladed is better....I'll send back the 2 bladed hub.....

Does this make any sense????

Hello, I just ordered a Koolprop (Lugaprop?) from Vassili @ http://www.airtrikes.net/introduction.shtml 

I am replacing my inflight adjustable Warp drive/GSC gta hub combination.

I ordered the scimitar shaped model, 2 bladed as I find it much more convenient to fold my wings that way (avid Catalina). I did some lengthy investigating/ reading for the 2 vs 3 blade debate especially for the rotax 912. In the end it seems it comes down to the looks of your prop more that anything else (also second by the Sensenich guys I questioned about this). The 3 bladed prop is better for the 2 smokers as it tends to reduce vibrations. The 912 is pretty smooth and does not need it as much...

Also it seems fuel economy can be made with the 2 bladed prop (better efficiency). Last and not least, there is some weight saving in favour of the 2 blades. 

To ad an other info I found about the blade shape (e props,scimitar, sabre, straight etc...) it seems that the scimitar shape is best suited for pusher applications in slower flying aircrafts. (I know there are some fast overpowered turboprops out there with scimitar blades like the saab2000....another subject all together)

As soon as I have flown with my new Koolprop I will give you some feedback

Cheeeers

Thank you everyone for your valuable inputs.

The one of the many I tried was Uship....I will look into roadie.com for a quote. Also worth mentioning is that the wings being very fragile they mut be put in relatively solid crates to be shipped (I have read of many shipping companies who don't care and do damage)  and that makes it fairly big ....hence the high price I guess. I probably will end up building a set of wings as tjay suggested. 

Anyhow if any of you is driving across let me know

Cheeeeers

Hey everyone,

I really am interested in buying a set of Catalina wings but.....they are in Batesville, Indiana. I am on the west coast up in Vancouver. I have inquired about shipping cost and the price is pretty hefty..3400-4200us not including the crates (that is shipping only in usa, not across the border)....Me driving the round trip is a 8-10 days endeavour (1500us fuel+food+ motel etc). Flying in / driving back a rental same price..

Does anyone have a suggestion or idea in regards of shipping/moving aircraft parts across the US??

I really appreciate your suggestions at this point

Cheers, Laurent

Thanks for your input Paul, I checked my trim tab horn after Cowlove had the same happen to him on his Catalina.

Cheeers, Laurent