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Fastest LSA?


Guest Howard Hughes

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I believe the rules allow a descent of X many feet over y distance in the speed record. Don't know the actual numbers

Yes and no. If its FAI (and the Risen is an FAI record claim) you can have minimal decent between the two runs BUT the exit heights for each run has to be at least as high as the entry height and have to be you have to reverse the run in the opposite direction and the claim is on the average...FAI Sporting Code - Section 10 – 2015 page 7

3.14 Special rules for speed over a straight course.

 

3.14.1 The course shall be straight with a minimum length of 15 kilometres.

 

3.14.2 Before crossing the start line the aircraft shall fly level for the last 1,000 metres within a tolerance of 100

 

metres.

 

3.14.3 The altitude of the aircraft at the finish line shall not be less than its altitude at the start line.

 

3.14.4 The speed adopted shall be the average of the two speeds from two consecutive runs over the same course

 

in opposite directions. The two runs must be completed within a maximum elapsed time of 1 hour with no

 

landing between runs.

 

3.14.5 The altitude at which the aircraft crosses the start line on the second run must be within 100m of the altitude

 

at which it crossed the start line on the first run.

 

 

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kasper - Now you are talking! There are a lot of fast/sexy looking aircraft out there with truly wild/unverified performance claims. A truly informed observer/purchaser looks for the independent assessments on which to base their opinion - all else is wishful thinking .

 

Check out the CAFE Foundation that hosts NASA's PAV Centennial Challenge for small aircraft, - wikipedia.org/wiki/CAFE_Foundation

 

DGLFox/ Sting, might like to check out the Pipistral Virus SW (also on the RA Register) two time winner of the CAFE - may not look as fast/sexy as the Sting - it doesn't have to as its independently verified performance makes the Stings unverified performance look positively anaemic.

 

 

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Yep - FAI make you measure speed over distance by GPS, each run has to end at least as high as the start height, average it over 2 runs, make sure the runs are not time distant (avoids wind shifts) and not significantly altitude different (avoids differing winds) AND makes you fly straight and level for 1km before the entry gate to avoid diving in for added speed. And to kcik it all you have to have it independently observed and verified by FAI review of docs.

 

CAFE is different but still solid on performance.

 

Manufacturers tell advertising fibs ... eg the EclipseR 912 in my avatar used to be advertised at 70mph cruise ... reality was that yes you could do 70mph cruise but that was at 4400rpm and 13LPH fuel burn ... but mostly you cruised at 4200rpm and burned 11.5LPH but got an honest 68mph over 2-3 hours of flight ... those last 2mph to get a nice round 'advertising' number cost you 1.5LPH!

 

 

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kasper - Now you are talking! There are a lot of fast/sexy looking aircraft out there with truly wild/unverified performance claims. A truly informed observer/purchaser looks for the independent assessments on which to base their opinion - all else is wishful thinking .Check out the CAFE Foundation that hosts NASA's PAV Centennial Challenge for small aircraft, - wikipedia.org/wiki/CAFE_Foundation

 

DGLFox/ Sting, might like to check out the Pipistral Virus SW (also on the RA Register) two time winner of the CAFE - may not look as fast/sexy as the Sting - it doesn't have to as its independently verified performance makes the Stings unverified performance look positively anaemic.

Skippydiesel..Yes I should have said one of the fastest LSA's..

 

David

 

 

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My apologies to all - I made a classic mistake, I got myself fixated on aircraft fitted with Rotax 912's (just a little bias showing).

 

Of course there are faster aircraft, they tend to have larger capacity direct drive engines and stubby wings. For the most part are only RAA legal with one person on board, need very long runways & fly with partial fuel, but they are legal, JUST! These aircraft wont win a CAFE Challenge - they burn to much fuel and don't carry two people - in other words they are not very efficient but some are very fast.

 

Still VH SGS / Sonerai built by Robin Austin could be registered RAA, carry two people and with only a Rotax 912 (100 hp) is able to take on aircraft commonly using engines of 150 + hp and do it all on nearly half the fuel (unleaded) burn - that's truly fast and efficient.

 

 

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Check out a plane called the Millennium Master,.

Yes it would be fast because it is tandem seating, if you can make the aircraft very slim in profile so it should go fast, although they are saying it has a cruise of 140kts which isn't that fast when you consider the seating arrangements and the general size of the plane and it's weight.

I think if we are comparing speeds we should stay with the conventional side by side seating configuration like the majority of LSA aircraft are here in Australia. I think they have gone bust anyway as I can't seem to find a website anyway.

 

David

 

 

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KP 5 or sabre ,120 kts at 5200revs 34 map it will do 130kts at 5400 36 map but gets thirsty at the higher speed nearly run out of forward trim ,staggered seating which narrows it up a bit, retracts help also

 

 

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They're not LSA but the fastest RAAus registered aircraft, probably the RV's (not rv12) but the ones that can squeeze in under the limits. RV3, RV4?

My RV-9 (RAAus rego) was showing 163-165SMPH TAS last week, at 9,500 during testing. That's without any fairings installed and those should bring it up to 180MPH+ depending how much fuel I want to use...I haven't verified the ASI & static ports as yet but it does compare favourably to Vans published numbers.

 

 

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My RV-9 (RAAus rego) was showing 163-165SMPH TAS last week, at 9,500 during testing. That's without any fairings installed and those should bring it up to 180MPH+ depending how much fuel I want to use...I haven't verified the ASI & static ports as yet but it does compare favourably to Vans published numbers.

What engine you running in that KR? not sure how they would get in under the 600kg for RAAus...I see it has the required stall speed...not sure about the MTOW though...

 

David

 

 

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A de-rated O-340. Still puts out 165HP, but can run mogas no worries. I'll be the first to admit I am payload limited, I need to lose 10lbs to be able to fill the tanks solo, but 1/2 fuel still gives me the ability to take one of my kids for a 2 hour local junket and stay under 600KgMTOW. Still, it meets my requirements perfectly for now.

 

 

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KR - RV 9 nice aircraft! Always liked the look of the RV line - BUT! the use of SMPH (165 smph = 143.4 Kn) is giving you a false sense of performance when compared with Virus SW, Soneri & a host of other Rotax (100 hp) powered aircraft that can equal or better your cruise speed, lower stalls about half the fuel consumption and longer cheaper service intervals which all equates to much lower running costs. True your RV may be able to out climb most of the Rotax powered aircraft but countering this is the length of runway you require to TO & land.

 

 

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True, but have you priced some of those LSA's lately? The QB kit for the Virus is well north of 100K AUD, and that's before you add $20,000 worth of avionics, shipping and GST, realistically, you would probably be approaching $150K as a completed cost, more than 50% higher than what I have in the RV, for what I see as less performance.

 

The Virus SW also achieves its performance with an extremely high aspect ratio wing, so you need a bigger hangar for it. It's published cruise speed (100HP version) is only 147Kts at 75% power, and it can only lift 400Lbs payload (for the 1042Lb TOW version) or 650Lbs for the 1322Lb version. You can get 3 or 4 RV's into a hangar that you could probably only fit one or maaaaybe two Virus's (Virii?!?) in, and those RV's will go faster than a Virus, climb (much) better, carry 250-300lbs more than a Virus and do it while only burning 1GPH more.

 

That being said, the Virus will lift that 600-odd Lbs while remaining within the constraints of CAO95.55. I only have 370Lbs of payload before I run into the 1320Lb limit, so a definite plus there!

 

I have electronic ignition on mine, and I will be running mogas when I finish Phase I. I have automotive plugs in the O-340, so other than possibly oil changes (if you subscribe to a 50hour oil change in the 912) and a $6/hour fuel difference, the costs are pretty similar. I suspect insurance would also be a lot less for the RV series than a Pipestral, but that is my suspicion only, I have nothing to base that on, other than "they look pretty expensive to fix if you break it"!

 

Notwithstanding the above - and that I have an RV so am naturally biased - the Virus SW is both an attractive looking airplane and functional, if you can afford it. But outright speed is not what I was after when I built the -9, and I definitely couldn't afford something from Pipestral, much as I tried to make the numbers work.

 

If you are building an airplane to go far and fast, I've always felt a 914-powered LongEz or VariEz would be the perfect combination. But I can't afford one of them now either..... :-p

 

 

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I need to add a two feet extension to each wingtip of my Lightning Bug to bring the stall into the LSA range! I wonder if a single seat, Rotax 912 powered LSA that cruises at 160ktas+ would interest anyone...

 

It currently TAS's at 170+ktas (GPS verified) in its current configuration at maximum continuous cruise power and we expect more from it with the IFA prop that is about to be fitted to it. Detachable wingtip extensions to make it LSA legal have and will continue to be considered if we feel that there may be a market for it.

 

 

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A de-rated O-340. Still puts out 165HP, but can run mogas no worries. I'll be the first to admit I am payload limited, I need to lose 10lbs to be able to fill the tanks solo, but 1/2 fuel still gives me the ability to take one of my kids for a 2 hour local junket and stay under 600KgMTOW. Still, it meets my requirements perfectly for now.

KR I don't understand why you would want to register your RV under RAAus rego, surely you would be better under VH reg being you have all the restrictions you described above, maybe if RAAus do lift the MTOW to 750kg at some stage you could bring it over then, I don't know how you could fly anywhere and be not worried about getting ramp checked and being found to be over weight and therefore illegal, as it stands right now you have a single seat aircraft.

 

David

 

 

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I need to add a two feet extension to each wingtip of my Lightning Bug to bring the stall into the LSA range! I wonder if a single seat, Rotax 912 powered LSA that cruises at 160ktas+ would interest anyone... It currently TAS's at 170+ktas (GPS verified) in its current configuration at maximum continuous cruise power and we expect more from it with the IFA prop that is about to be fitted to it. Detachable wingtip extensions to make it LSA legal have and will continue to be considered if we feel that there may be a market for it.

I'll consider taking just the airframe kit and be happy single seat ... I still have (inhibited from manufacturer in original packing crate) the 100hp mechanical fuel injected 2SI engine for one ...

 

 

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KR - did you really put an RV9 in the air for just $75k AU?? if so it must have been a squilian years ago (or you are a close relative of Dick V's).

 

I recently witnessed the deceased estate auction of a Seawind (near rebuild completion after an accident) with its 300+hp engine (supposedly 0 timed by Hawker Pacific), CS prop, etc, sell for $27k AU, so great deals do happen.

 

I fly RAA to keep costs as low as possible, so + $6/hr sounds a bit rich to me (around here it would be more like $7) In truth, I suspect you might be closer t0 an extra 4 gallons/hr = 15 litres or $22.50 ULP/hr). I fly 80-100hrs/annum - go do the maths.

 

Virus SW is not cheap by LSA standards, but assuming day VFR only, I don't think fitting it out with $20k of instruments is either necessary or cost effective - $5-10k should do the job very nicely.

 

True the SW wingspan is somewhat wider/longer than many small aircraft but then you can always park your RV( tail dragger)'s under the wings.

 

I change my 912's oil every 50 hrs (only 3 litres) but as I run only ULP, I am told I could go to 100hrs. (I also service my cars under the "extreme conditions" intervals just because it satisfies my inner obsession.)

 

The Rutan type aircraft are very attractive (as are RV's) but few of us are just after speed, things like TO/landing role, stall speed, noise levels, rough filed capability & comfort become a significant part of the consideration.

 

 

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Speed has it's disadvantages. It costs in fuel ,you often get a rough ride depending on wing loading etc and the design has to be a lot more sophisticated, and stronger (flutter, fairings, landing speed etc) Low levels get a lot of turbulence during hot conditions, unless you get above say FL 120 plus especially in the afternoon. Nev

 

 

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KR I don't understand why you would want to register your RV under RAAus rego, surely you would be better under VH reg being you have all the restrictions you described above, maybe if RAAus do lift the MTOW to 750kg at some stage you could bring it over then, I don't know how you could fly anywhere and be not worried about getting ramp checked and being found to be over weight and therefore illegal, as it stands right now you have a single seat aircraft.David

This is perhaps the most common comment I hear about having only the second RAAus RV-9, but for my requirements, it is still perfectly adequate. If CAsA want to ramp me, I'll even offer to provide the scales...My BEW is 445Kg, so I have 155Kg payload. Fuel fuel weighs 100Kg, so if I can lose a few more pounds myself, I can (nearly) fill the tanks. My young bloke weighs 20kg in his carseat + my approx. 75-80kg and I have 55Kg fuel, or 70Lts, still enough to go to Brisbane or Melbourne with reserves, or a 2 hour local junket.

 

KR - did you really put an RV9 in the air for just $75k AU?? if so it must have been a squilian years ago (or you are a close relative of Dick V's).

No, I'll have around $100K in it now, but I've only just installed ADS-B and bought the autopilot servos...QB fuse & wings, brand new engine, polished with vinyl stripes and an interior I sewed myself. 150% of my cost of 100K = $150K for the Pipestral. You can easily put an RV in the air for under $60K if you are willing to compromise on what you fit and accept the standard kit build times.

 

I fly RAA to keep costs as low as possible, so + $6/hr sounds a bit rich to me (around here it would be more like $7) In truth, I suspect you might be closer t0 an extra 4 gallons/hr = 15 litres or $22.50 ULP/hr). I fly 80-100hrs/annum - go do the maths.

I certainly wouldn't be burning an additional 4GPH on top of the published figures for the Rotax, I'd be lucky do be 1.5GPH over those figures, but even so, that's a cost I was willing to bear. As Vans say in their advertising, $50,000 difference in purchase price buys a lot of fuel!

 

Virus SW is not cheap by LSA standards, but assuming day VFR only, I don't think fitting it out with $20k of instruments is either necessary or cost effective - $5-10k should do the job very nicely.

$6,000 for a 10" dynon screen, 1900 for the ADAHRS module, 900 for the engine module, $750 for the GPS, and $3,000 for the transponder, it is easy to run up the costs. I don't need an EFIS or Autopilot or Mode-S in the RV, but it is lighter, and provides a lot more capability. If you are going to use the speed of an aircraft, short of going to Reno, then you're going somewhere, and an autopilot and EFIS makes a lot of sense, even taking into account the costs.
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KR - Your RV sounds like a real beut. I am sure you would detect just a little envy in me should I ever have the privilege of seeing it - I wont argue with your RV in the air for under $60K costs, but remain sceptical, sorry!

 

A year or so ago I had the privilege of a " joy flight" in a plans built RV4 from Wedderburn NSW - the fit/finish, down to the smallest detail, was pure art, way better than any factory build. After a barrel & aileron role or two I was ready to go out and buy my own - a truly wonderful aircraft and pilot/builder.

 

A long time ago I used to fly Cessna 172's (up to constant speed/retractable level) 150 -180 hp engines, if a remember correctly (always a concern) I planned for fuel burns of about 32 - 38 lph. In my Zephyr/Rotax I plan trips at 14 lph and actually use less than 13 lph, one up and 13.5 lph, two up, at 100-105 knots indicated. I can cruise faster, up to 120 + knots (but why?) with commensurate fuel burns up to about 18 lph (bit hazy as I don't often go here). For local flights I usually see consumption rates of 8- 10 lph or less for the "mission". I know of no aircraft petrol engines of similar hp (other than Rotax 912is) that can come close to these "real world" sort of fuel flows. For even better independently verified figures check out VH SGS / Sonerai built by Robin Austin.

 

Oh I know the "sky's the limit" with avionics and if what you have fitted suits you (& your pocket) more power to you. I like to keep things simple (& cheap) - small round dials for the most part. I have splashed out on a KT74 (ADS-B) transponder (not required but I like the enhanced safety), an iPad mini/OzRunways, a Garmin GPSMap back up (both on RAM mounts) and for fun (& some added awareness) an AVMap Ultra EFIS. Once in a while I contemplate an autopilot but so far have resisted. I fly out of a very "dodgy" home strip, so have my ground adjustable prop pitched/optimised for climb - would be nice to have an in-flight adjust or CS prop for cruise (enhanced speed/economy??) but at $9-12K (including governor & engine mods to suit) for a reputable unit, I don't know if this will ever happen.

 

You can put an all new ATEC Zephyr (very quick build) in the air for about $90 - 95K, an all new Faeta (all carbon,factory build) will cost somewhere in the region of $120+K depending on engine/avionics choices etc.

 

 

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I like the Piper Sportscruiser also. I recently had the opportunity to have a good look over one...024_cool.gif.7a88a3168ebd868f5549631161e2b369.gif

 

The BRM Bristell and Arion Lightning are similar types 080_plane.gif.36548049f8f1bc4c332462aa4f981ffb.gif

 

Interestingly, I've started another Thread enquiring about the RV aircraft going onto the Rec Aus Registry.

 

I was particularly interested in an RV 4 - removing rear seat, harnesses etc to bring it down from MTOW of 680 kg approximately to sub 600 kg.

 

As above comments note, I think the opportunity of Rec Aus being moved to 700 or 750 kg will provide some great opportunities for both RV and other designs.

 

I sometimes wonder if reducing weight with composite or other light weight materials is really ideal in trying to stay sub 600 kg. Also the fine balance between fuel levels is also a bit if a worry if fuel needs to be left out - ullage - to meet MTOW.

 

Again the Piper Sportscruiser seems a really nice little all metal aircraft 080_plane.gif.36548049f8f1bc4c332462aa4f981ffb.gif

 

 

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