skippydiesel

Kyle - you sound a little coy - a bit of this and that and some sugar to wash it all down. I expected more punch!

In LSA class aircraft, I think the cost of any inflight adjustable/CS is indefensible. What I mean is, those that purchase one are not so concerned with the cost effective rational. They want the effect and the cost is just a pain to bear.  Its not rational, so lets put that point to one side.

The additional weight of most CS props is a concern but again manageable. It would be better not to have a significant weight change - hence my interest in minimising this factor AND my interest in the Eprop development in this area

The question for me is - can I find a prop that will equal, my very satisfactory (see my erlier descriptions), existing ground role/climb out AND give me a higher/more economical cruise speed. My existing prop can be adjusted to do both BUT not during flight.

1 hour ago, Kyle Communications said:

A.........................................................

 

"Our range of variable pitch propellers is currently being tested. Deliveries not before mid-2021, and no prices for the moment, because we have not finished the production machines, so we can't calculate the cost prices.
The performance is amazing and the weight... 3,4 kg for the 3-blade, 4 kg complete with spinner all inclusive."

 

..........................................................

 

 

That's great Kyle - would they like an Australian test aircraft/pilot?

Weight is amazing. This is addressing one of the main drawbacks to CS  props - the changes to W&B and reduction in "pay load". Does this weight include all the actuating mechanism/system ??

The Airmaster recommended (for my engine but I dont think the aircraft) prop is 11.2 kg over the nose. This is 7.6 kg more than the existing prop. Given the location, I would suggest that this is a significant change for a 297 kg aircraft. My Airmaster choice is a little lighter at 9.1 kg - a step in the right direction.

With your insights to propeller performance I would have thought you might have been interested in the Airmaster recommendations versus my selection ??????

I have an enquiry in with MT - Propeller. Hope to get some answers in the next day or so.

Hi Blue - I am very happy with the performance of the Fiti  2 blade ground adjust in: 

• Ground Role - sub 100 m on grass
• Climb out - 1500 ft +/min @ 60 knots

The prop is very effective even, at idle (no brake applied) it will move the aircraft quit rapidly on relatively smooth  level ground. If I reduce my idle further the engine will stall.

• Approach to landing. The prop is still delivering  some thrust in the landing phase - not so good but manageable. Combined with a tail wind, the unwanted thrust can make things a bit too interesting at times.

I would like my new prop to deliver at least equal ground role & climb out to the Fiti . Then give me a better cruise speed that I can chose to maximise economy or speed, as the whim takes me. Then in the landing phase, reduced thrust at idle, with the option of a full power go round should it be required.

All good stuff!

I thought I might get some comments on the Airmaster recommendations versus my choice - anyone?

1 hour ago, spacesailor said:

I am told the, scimitar prop will  " bend " giving a little pitch reduction on take-off,

Max revs on take-off and A corser pitch on cruise revs.

spacesailor

Hi Spacesailor - I have read commentary on this sort of propeller befor - seems a little like magic to me - I get the idea but does it  work effectively in application ? If it does do the blades fatigue over time ? If so what is their operational life expectancy ?

Kasper - Thanks for that.

My actual performance figures (speed in indicated knots) pilot (me) & full fuel is:

Static  5200 rpm

Elevation 1100 ft ASL

Ground role sub 100 m on grass

Rotation 40 knots

Climb out 1500 + ft /min @ 60-80 knots - 5200-5500 rpm

Cruise climb  5400, above 2500 ft, 100 knots,500 + ft/min

Cruise 100-110 knots 5000-5200 rpm  - sub 13 - sub 14 L/hr.

Have seen 120 knots, strait & level, at 500 ft (beach run)

Stall  - sorry dont have a no flap figure but in landing configuration sub 30 knots

Final approach 55-45 knots

Planning  - conservative  14 L/hr

Factory claim 125 knots for max cruise. If anything they tend to be a little conservative. There is complexity/differences in the standards as applied to the European compared with Australian operating environment 

So what think you - slippery? or draggy? or somewhere in between??

9 minutes ago, facthunter said:

Depends on where you operate from. ....................................................................................f not over trees just after take off which is bad news anyhow. Nev

 I think you must know where I fly from - got it all;

Almost all TO to the east Landings to the west. In 11 years have TO to west twice and Landed to east once. Personal max tail wind component 10 knots.

A lot of tall trees at eastern end

Trees power lines , stock yards at western end

About 100 m, sort of level area, at western/stock yard end thereafter sloping steeply to east befor crossing ephemeral spring at bottom of slope. Spring can reduce available landing distance by 1/3.

This quote from the last paragraph of the Foxbat article pretty much says it all:

"My conclusion – while a CS/IFA prop may have big advantages on a more slippery, faster cruising aircraft, the benefits for the Foxbat are more debatable. If you want to be able to run on the limit for the complete flight envelope (and your pocket can handle it), maybe a CS/IFA prop is worth it. Me? I like the simplicity of the Foxbat and the take-off performance is more than enough for all but the most extreme conditions. So I’m happy with one of the standard props."

So is my ATEC Zephyr in the "more slippery, faster cruising aircraft" category or is it more akin to the Foxbat ????

8 minutes ago, facthunter said:

Yes the article is quite reasonable. ............................................................ wheras a properly "tailored" fixed pitch for a particular  speed. CAN  IF this is done for your cruise  speed it will out perform any CS at that speed as well as being lighter and cheaper and more reliable..  Nev

Hi Nev - I have no doubt that you are correct however the question is: where to find such an air screw ??? and how will effect my TO/Climb out ???

Seems to me that the CS prop is mans attempt to achieve the best compromise in propeller application for most situations.

If you just want great TO/Climb performance there is a prop for your aircraft.

If you just want best cruise (speed/economy) again there is likely to be a prop out there somewhere.

BUT how do you archive some reasonable semblance of both in the one installation?? without going to a CS

Thanks Thruster - I have been "operating" from my paddock/strip for about 11 years now. Every TO/Landing is "short field" and  just a bit nerve wracking. 

With full fuel & just me (always), TO role is under 100 m, climb out 1500 ft/min, from  a 1100 ft ASL grass strip, with my ground adjustable prop adjusted for what I call advantage TO/Climb (not fully optimised).  This is pretty good by most standards but of course my cruise speed 100-110 knots, 5000-5200 rpm 13-14 L/h is compromised. By how much????  

Well it has been suggested to me that if I was in a position to optimise my ground adjustable prop for cruise I might be able to achieve a max cruise  (5400 rpm) of 125 knots plus, so an economy cruise of 115-120 knots possibly ??????

My existing Fiti prop is no more (accident) so must be replaced. I have a few months to make the decision -

Go with the  2 blade Fiti Eco  ground adjust, I know so well and have a high regard for OR replace with something else of unknown benefit (CS) that may give a more flexible performance???

Decisions Decisions - all help gratefully received.

This attached article on CS prop use on Foxbat is, in my mind, a very balanced article:

https://foxbatpilot.com/tag/constant-speed-propeller/

Comparison of Fixed and CS propellers corrected.pdf

Okay this may get some interest/conversation going:

Its going to be quite a few months befor I must make a decision, but that's a positive, as it gives me time to discuss the matter with you(s) and digest all the feed back (ha!?)

At this early stage I favour Airmaster:

"Airmaster AP420CTF-SNR70E (Sensenich) - 9.1 kg. Almost local (NZ). Not a prop maker as such. Great reputation. Lots of technical information on web page."  About $12 K (delivered)

HOWEVER Airmaster are recommending the "AP332S fitted with blades WWR68W ( or possibly 70w) by Whirlwind". This is their standard/generic Rotax 912 offering. It is a more complicated airscrew and is 2.1 kg heavier than the AP420CTF. Strangely with an extra blade & mechanism it is only slightly more expensive than my choice.

Airmaster have referred me to the attached informal propeller testing/comparison test: 

From this test, using a Tecnam P 92 (sharing the same engine type but otherwise a very different aircraft, in almost every way to the ATEC Zephyr)  you will see that the AP420CT appears to perform as well as the AP332S with the possible exception being noise generation. The noise issue may be  significant in a sheet metal aircraft but is unlikely to be so in a composite one.

I look forward to an avalanche of comments/advise

55 minutes ago, 440032 said:

........................................................Unwarranted and uninformed Jabiru bashing needs to stop.

 

What and spoil al the fun?  --------- what would we argue about ?  Rock on say I

1 hour ago, RFguy said:

OK I will do it.

it probably needs a pulse just long enough to engage and then needs to back off a bit to reduce the peak torque load for a short time. It will be interesting to  measure  how much is required to get a solid engage. It will be pretty obvious to the sensing circuit when the engagement has happened.

 Good -on -yah! Jabs, so fitted, may start to catch up with Rotax 912/914 range that have had soft -start for quite a few years now.

11 hours ago, blackhawk799 said:

Do you know much about the europa monowheel?

On this particular aircraft ,not much more than is in the advert (I have a letter from the owner as well).

Europa Monowheel in general - I almost bought one recently. After months of truly exhaustive research on the mark, several hours static inspection of the aircraft itself, in my mind  was the owner, I went for a fly - came away very sick (CO poisoning) & disappointed.

Europa aircraft have been around for ages. Designed by Ivan Shaw (a Pom) as a trailerable, grass runway, high speed economical cruiser specifically designed for the Rotax 912/914 engines (others have been fitted) and CS propeller, blending glider and light aircraft composite/foam build technology. There was a later larger tricycle factory (certified) development of the airframe using a conventional aircraft engine

All are kit/home built, so scrutiny of build log and research into builder is a must (this one sounds good as won an award and built by LAIM).

A truly ground breaking concept.

Removable wings (needs two competent handlers for safe fast removal/assembly)

Tail dragger with retractable mono wheel & balancing outriggers. Flaps deploy at the same time /action as the wheels. (There are both conventional fixed main gear and nose wheel mods out there)

Specific to type TO/landing management must be learnt. You can down load the very comprehensive POH written by Ivan Shaw

By all accounts can be a handful on the ground (as with many tail wheel aircraft) but once airborne a delight to fly.

The fast cruise comes at the expense of a high stall, only just fitting into RAA specification of 45 knots. 

Fast and economical cruisers (the advertised one cruises at 120+ knots on 80 hp and I believe it)

Those that have them, love them. I know of one pilot who has two (Rotax 912 ULS & 914 powered)

This aircraft is the Classic. The later development is the XS. Main differences are lengthened tail wheel for better ground control (this aircraft has the upgrade) different engine cowling and spinner. The aircraft I nearly purchased was a Classic but had all the XS changes done during the build process.

There are not large numbers in Au but the group is strong & supportive. There is a Europa Club based in the UK that will answear many of your questions.

It seems to me that the CO problem is wide spread. The  problem seems to be when taxying and in most clears as soon as TO achieved. For sensitive types (like me) it may be fixable but most of the pilots I have spoken to, on this topic, just accept them the way they are. 

This particular aircraft is very well priced which may allow the purchaser to do a few upgrades eg fit the recommended Airmaster CS prop and/or a new 912ULS (100 hp) engine

Are you guys serious?

I gave you leads on 4  low wing aircraft (as stipulated) all powered by Rotax 912 (as stipulated) - all under $80 k (as stipulated) all capable of economy cruising above 120 knots for a ULP consumption of 16-19L/h or so AND you start talking about high wing rag & tube that will be lucky to see 105 knots flat out.

Perfectly legitimate however me thinks your just having a fantasy 

Pioneer 300 Kite - above in Plane Sales

Pioneerr 300 Hawk RG - $80k Sport Aircraft Sales

Seem to be quite a few when you actually take a look

Pioneer 300 Kite - $81K

11 minutes ago, RFguy said:

No low wing composite comes to mind.

high wing- J230

 

anyone else got some low wing composite touring ideas for RA ????

 

230 is I think best RA option for touring... Have you defined your mission ????

 

. has by far the best stowage options of anything in its class. i think.....that's because its a 4 seater without the rear seats.

you can buy a J430, remove the rear seats and turn it back into J230 for the RA reg

right price 55-75k there is a  500 hour J430 in victoria in Wangaratta with autopilot and all the stuff for $65k

they come up regularly enough.

 

 

J 230 Good aircraft - you cant use all of its luggage (weight) capacity under RAA 600 kg - do the maths and you will find that its empty weight compromises its lifting potential - other aircraft have empty weight of 300 kg (+- either side) can lift more.

Just checked out Plane Sales Europa/Rotax for $38K - be hard to find a better cruiser

1 hour ago, kasper said:

Never found the torque rods to be a problem.  My issue with the prop - and the reason I changed it out for a fixed pitch - was it really didn’t seem to do much to the performance. There was not enough difference between fine and course and it just didn’t add enough performance.  

This is the sort of feedback I like to see - real life experience & sound logic.

Unfortunately I seem to have posed a question(s) that strangely few are interested in or alternatively have no experience in (doesnt usually stop people from commenting). I say strange because most pilots are looking for that little something that may enhance their aircrafts performance and a CS prop will do that. The cost benefit is questionable in most instances but their is no doubt that a CS prop will give you the best combination of TO/Climb/Cruise.

Recently advertised;

Carbon Sting - ex trainer with high hr motor but if you got it for the right price you may be able to put a new Rotax in and still stay well under the 80k

Pioneer 300's X 3 

The occasional ATEC Zephyr comes up but usually sold by word of mouth. 

There was an ATEC Faeta for sale - based in Gladstone but owned by a bloke in Narrabri

The existing Au Zephys have a 545kg Max TO but the Faeta has the full 600kg. The Faeta is currently configured for towing gliders  - if you want better all round performance you will need to get/ cost in the 2 blade ground adjust Fiti propeller.

1 hour ago, RFguy said:

Why buy a Tecnam Sierra  when you can buy an a high end RV for similar money ? 

 

No comparison in my book...

 

There are plenty of RVs for sale between 70k and 110 k. 

 

In fact - why not buy a Brumby 600 ? there are a few around for sale 60k-80k. Suggest for touring, only consider the later 600kg version due to more useful  CoG position.

 

 

I have always lusted after an RV 8 BUT having now flown RAA class aircraft for about 11-12 years I would not go back to GA (unless I suddenly had an unforeseen need for more pax/higher pay load) WHY ? you may ask:

• Well I like to fly,  up there with the Gods, so the trip time in not so important.
• Over the years the demand for seats on the aircraft I fly has dwindled from having a waiting list (when I flew GA) to a rare passenger. So having  extra capacity is unnecessary.
• The cost of operating a GA aircraft is generally (there are a very few exceptions) much higher than for RAA types
• RAA aircraft are comparatively, to most GA,  quiet (in & out), bettered only by gliders, a feature I have come to like very much.
• RAA aircraft are supposed to have a stall speed max of 45 knots (mine is about 30 knots) this is a very important safety feature that will allow most pilot/pax to survive any controlled forced landing.
• Personally I like the simplicity of a near basic instrument panel - most GA will be far more complex. Sure you can spend the big $$ for a more sophisticated set up but it is in the realms of personal choice.
• Etc

Rather than look to GA, I would suggest broadening your search to composite aircraft - to my mind vastly superior aircraft building/construction material to metal.

1 hour ago, jetboy said:

I cant add any crtique for the 4 CS props you have narrowed choice to,

 

for my VP project the powerplant was set up for Airmaster but I wouldnt need a full CS system just inflight pitch change and with 90 SHP to run I think the lower power version of IVOprop would do fine

 

https://ivoprop.com/

 

They have been around for ages and despite them looking like the blades are about to peel off the 2 attach bolts at any moment i've seen no trouble with them. Probably not as efficient as the other types because of the flat taper, the cost and weight is low.

 

 

Thanks for the suggestion Jetboy - checked out the web site. Veeery interesting. Unique approach - a twisting/warpable blade - first impression: a bit scary! So different from all (most) others who follow the convention of rotating the entire blade rather than changing the aerofoil itself.

Certainly follows the KISS principal but as you say may give up some efficiency in doing so.

I wonder a bit about the adjusting/torsion rods fatigue life. Its one thing to use it as a ground adjust but to use the sam system for inflight (regular/constant) adjustment could be a concern.

1 hour ago, Squidget said:

Im looking at purchasing my first aircraft soon , im looking at a tecnam sierra, its been regularly used in reasonable condition with full books.

..........................................................................................

I cant wait to be able to enjoy it 

Tecnam make excellent aircraft BUT remember they are predominantly metal and metal corrodes /fatigues.

Despite your familiarity with this aircraft, get a third party (ex[pert in Tecnam Sierra maintenance) to do an in depth check befor you purchase AND with his assistance do a pessimistic annual maintenance budget for the future upkeep.  

The Rotax 912, that motivate them, is easy and relativly cheap to maintain and will have the same demands whatever the aircraft it is fitted to, so from a maintenance/operating perspective, the distinguishing aspect is the airframe construction material - metal aircraft will almost always have a higher on going maintenance cost that a similar type of composite aircraft.

The GA advice might be a bit optimistic:

Most GA's will have much higher fuel consumption (old 172's & similar around 32 L/H of AvGas). This makes for higher fuel load requirement and consequently lower cargo/pax availability.

My Rotax 912 ULS Zephyr has the capacity to carry  nearly 300 kg fuel + pax + luggage at 100-110 knots for a ULP burn of 13-14 L/H

GA's in the sort of price range you seem to be hinting at, will likely be slower, use more fuel and have less luggage capacity at full fuel than many RAA types AND require a lot more maintenance/operating costs

"But Id go an old certified GA everytime over a slightly newer but owner maintained RAA as a first purchase." - Please expand on this rather sweeping statement