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TomSw1ft

How to buy a motorglider: help wanted

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TomSw1ft

My airplane partner and I are looking to sell our ELSA airplane and replace it with a motorglider.  Neither of us have experience in motorgliders, both of us have lots of taildragger time, and retractable time and I am currently working on getting a glider add-on (8 flights in past two weekends).  , (Apparently, I will need to do the flight test and self-launch endorsement out of state as we have no FAA examiners for either here in Nebraska).

In my usual OCD way, I have built a spreadsheet with the various options available right now.  Several are Super Ximango S200, two are Distar/Urban Air Lambada, plus a couple of SunDancers and Diamond KHK36TC or Katanas, at least two Pipistrel Sinus Flex, and one appears to be a pretty nice Grob 109B. One of the Ximangos and one of the others had a belly landing and both are reportedly all fixed up now - good as new).  Some of these aircraft don't seem to have been flown much in the past 12 months or more.  

Very few have all the features I think would be good to have:

  • Two-place
  • Folding wings or removable tips for hangaring
  • 110-120 knot TMG cruise
  • Prefer Rotax ULS or S 100 hp, but 80hp OK if cruise 110 knots
  • Ballistic chute
  • ADSB 2020 compliant
  • Budget not much above $120,000
  • minimum 27:1 glide ratio, 31 preferable.

Has anyone written up a report that compares these various ships in terms of

  • how they fly
  • what's it's like to live with one
  • how much they get flown as gliders vs. slow cross country machines
  • how long owners keeping use them
  • is my impression correct that many of them sit in hangars for a long time unloved?
  • relative hardiness among the breed (my CFI partner may want to instruct in it)
  • what to look for before buying
  • the names of trustworthy people one might hire for pre-buy inspections (only EAA friends in our area have a clue about Rotax engines, for instance)
  • Whether I should make up my mind between a glider and a touring airplane because TMG are no better than mediocre at either (except, of course, the Stemme, I am told over and over, as though price were no option).
  • Should I buy a nice self-launching glider like a Taurus or a DG-500M  and haul it places i want to soar via trailer?

I'd appreciate any thoughts.  

 

 

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Russ Hustead

I have over 5000 hrs instructing  in touring motorgliders.  I'd be glad to help.  russ@skykingsoaring.com

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mikeschumann

You should add the Phoenix Motorglider to your list.  It is by far the best option available, even though it might be slightly above your budget.

It's basically a 2nd generation Lambada, solving two of Lambada's biggest problems:

1.  With the wing tips removed (takes 30 seconds; they weigh 15 lbs each), the Phoenix wingspan is 35', so it will fit in any standard T Hangar.  The Lambada and Pipestrel motorgliders have 41' wingspans with the tips removed, so they won't easily fit in any standard US T-Hangar

2.  The Lambada's cockpit is relatively short and the rudder pedals are not adjustable.  If you are 5'11", after an hour or so, you will be very uncomfortable.  The Phoenix has a longer cockpit and is very comfortable for 5+ hour flights.

The only downside on the Phoenix is a 2+ year wait to get a new one delivered.  There are about 25 flying in the US.  Each year, one or two become available on the US market.  Virtually all the Phoenix motorgliders in the US have Dynon Skyview glass cockpits with autopilots and ADS-B IN & Out.  In addition they all have ballistic recovery chuts.  They all have 100HP Rotax engines.  Cruising speed is 110 knots burning 4 gallons / hour with a range of about 700nm.  With full fuel you can carry 2 adults and 100lbs of baggage.

Jim Lee, the US distributor, provides exceptional support.  He is based in Minden and can give you lots of additional info.

Before buying the Phoenix, I almost bought a Ximango.  Two things totally turned me off.  With full fuel you barely have enough gross weight to carry two adults without any baggage.  The official baggage capacity is limited to 20lbs, even if you are only carrying partial fuel.  The absolute deal breaker for me was the folding wing.  It is VERY heavy and awkward, and scary to fold.  On the way down, you are holding the wing just above the hinge, and have very little leverage.  If you don't have the exact right technique, you will loose your grip and the wing will crash down causing major damage.  Before you buy one, make sure you try out folding the wings so you know what you are getting into.

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Todd

Hi Tom,

I only have experience with a Pipistrel Sinus Max that I purchased new Oct 2017 and operate here in South Florida.  It is the Tailwheel version that I would recommend as it has better soaring performance. I use it mostly for recreational soaring but on the occasional cruising flights I can usually average 110kt ground speed over a round trip on about 3gph.  The 80 hp Rotax is the most reliable engine you will find (other than electric) and easy to maintain.  I now have 332 hours on the airframe and just 127 hours on the motor.  I fly from a controller airport so it takes a little extra motor time to taxi and get out of controlled airspace to soar.  I have 48ah lithium batteries so 5+ hours of soaring is not a problem.  The tips go on and off in under 5 minutes for hangaring.  If you take the Light Sport Repairman course you will be able to take care of your own maintenance.  So far I am very happy with my Sinus and I will keep flying it until the Elfin 20.ex is available (Electric Stemme) but at 3x+ the price.  You can contact me if you have any questions at underh2oguy@bellsouth.net.

-Todd

F0B6F0EE-DACD-4CAD-B4BE-86A67B242F7A.png

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chasers03

All of the above inputs are great and should help guide you. I owned a lambada 80 horse for six years. Loved it except for speed, Vulnerable gelcoat and baggage capacity. It fit in my standard hanger.  The phoenix is a great airplane but be aware of the takeoff and landing site picture.

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Barry Stott

Tom:

You don’t provide either your full name or your personal contact info (email? phone?) in your recent “Which Motorglider” query to TMGA, so it is impossible for any of us to reply to you directly!

I think you are making a big mistake in rejecting a used Stemme S10 out-of-hand.  Many used ones go for less than $160,000...and they are so vastly better than any other motorglider that they are well worth their price.  (I bought a new S10 VT back in 2012 and LOVE the bird!!)

The Stemme uses the 115 HP turbocharged Rotax 914, and it is certified to climb to 30,000’ on the engine.  At 15,000’ and about 4700 RPM, I cruise at 129 knots on 2.8 gallons per hour, and with 31.8 gallons in the tanks, I have ten hours of range under power.  Obviously, if I do a “dolphin-flight” with soaring, my range can be extended a lot more.  Even more impressive, the S10 has a 50:1 glide ratio (and the S12 has 54:1) with a redline just under 150 knots. Compare those performance figures to any of the other lesser motorgliders like the Lambada or Sinus/Virus/Taurus!

The Stemme has roomy side-by-side seating, 40 pounds of storage space behind the seats, a convenient cubby for two O2 bottle (good for 22 hours with a Mountain High. M2D2 nasal cannula set-up), and the wings fold easily for T-hangar storage.

The only thing the Stemme lacks from your Wish List is a ballistic parachute, but the canopy is ejectable if you want to wear a parachute.  By the way, Reiner Stemme is currently building a new RS20e-Elfin all-electric 20 meter motorglider that WILL have a ballistic chute.... see it at    www.reinerstemme.aero

You can contact Edgar van Schaik or Wes Chumley at Stemme USA to inquire about used Stemmes that they have taken in trade for new S12’s or otherwise listed for sale:  (305) 922-6574 or (843) 300-9667.

Before you compromise on a lesser motorglider, at least take a demo flight in a Stemme!  With interest rates so low these days, getting into one would be easy.

Contact me directly if you have any further questions: ebstott@aol.com

Barry StottB0B3FAE6-EBF9-4013-8C3E-A94B9B6646DC.thumb.jpeg.e8758725d0130d9944462d2516099bb3.jpegimage.thumb.jpeg.ccdbb09e97a9d44c283f403b1a4997c5.jpeg

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Steve

Tom was surprised to see you are from NE! I live in Lexington and have flown gliders and motorgliders for 20 years. Contact me at sloudon54@ gmail.com

Best Steve 

 

 

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DermotMcD

Hello Tom,

I bought a TMG to go flying with my wife instead of her following our gliding safaris on the ground. The aircraft was bought from two previous owners who had owned it since new and put a lot of hours on the aircraft when new, and once they'd done what they wanted to do, flew it less and less. That being said, both jumped at the change of a 2000 mile delivery flight to say goodbye to it. If I had to toss up between an SLG and a TMG, I'd take the SLG but then I would be flying alone because she doesn't like flying in circles!

TMGs and SLGs are very different beasts and possibly only the Stemme does both sides well… at the expense of prodigious maintenance. I've flown gliding safaris in company with a Stemme and was very impressed. However the maintenance is huge compared with either SLG or TMG and that's normally reflected in the price of used aircraft.

I don't think that even the Stemme does better than 95 knots cruise and if 110+ is really what you are looking for, then nothing much which glides is going to do the job.

A real glider is a joy to fly when gliding. The Ximango and others like it, even the Stemme are OK but much heavier and less sensitive to thermals. Even the Stemme needs two hands from time to time in rowdy air. Typically, SLGs do about a ten minute motor run per flight which might be 2-7 hours. Typically TMGs I've seen have about 25% gliding time… ie the airframe has 25% more hours on the clock than the motor. Most TMGs don't do a lot of gliding and in some regions, LSA aircraft like the Pipistrelle are not allowed to turn off the engine… so owners have a lot of engine faults when in company with certified TMGs.

Most TMGs will go downhill pretty fast if you put the nose down when gliding. While they might do 32:1, it's only at slow speeds and they'd never keep up with most modern sailplanes which can retain a good LD at speeds over 90 knots.

SLGs, pretty much all of them, are really noisy vibrate and 95% don't cruise with power on. Perhaps only the Schleicher rotary cruises with power on but then at low speeds and big fuel consumption. Almost all SLGs have two strokes and/or short motor lives… 400 hours TBO and few motors actually make those hours.

In your suggested types, there are two classes of TMG. The old-school certified types like the Ximango and Grob and the newer LSA types. Without looking up the numbers, a Ximango has got an MTOW of 850 kgs while the LSA types are about 450 kgs less. Quite a lot of the extra weight of say a Ximango compared with a Lambada seems to go into the structure. I doubt whether if you had a tantrum in a Ximango that you'd do much damage, where most of us could wreck an LSA with a good kicking. In rowdy air, even on low finals, the Ximango is very stable and controllable. I doubt you could say the same with something 400 kg lighter.

I'm staggered at what a Ximango will absorb. An owner I know said the "Ximango is like a jeep, it'll go anywhere.' I'm not sure about the LSA ratings but Ximangos etc are certified to utility category - 5.4 G +.

There was a lot of talk about ballistic chutes in sailplanes 10-15 years ago. You don't hear about this these days. A proper sailplane is so slippery that if something breaks, it's accelerates really fast so the opening shock on a parachute is high and you need a lot of altitude to make it work. Then the glider tends to descend in a nose down attitude which isn't great. The weight of the chute and attachments are close to that of an engine so the result appears to be that people or manufacturers have chosen the engine over the chute. Another issue is the fact that most modern gliders are built light and strong to give a light wing loading which can be increased enormously with water ballast. Add a ballistic parachute and you lose this advantage.

Before I bought a Ximango, I spoke to a lot of owners, all of whom sung the praises of the 80 HP Rotax over the 100 hp… when fitted to the Ximango. With a wing section intended for gliding at slow speeds, most of TMGs don't benefit a lot from a big engine. 

The wing weight on a Ximango is an issue but it's easy enough with two people. The MTWO and fuel depends entirely on pilot weight. Back in the days when an average man weighed 75 kg, things were different. My wife and I are about 125 kgs total so we can go anywhere with full tanks. I think there's a way that older TMGs like the Ximango can be rectified to take another 5% .  However you'd have to add this as baggage because with two heavy pilots and max fuel load, the CofG is getting well towards the front.

HTH

D

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TomSw1ft

My contact info:

Bud Shaw

Omaha, NE

402-455-1581 land line

bud.shaw@gmail.com



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TomSw1ft

#DermotMcD Thanks for the long reply.  Very helpful.  Why is the 80 hp better than the 100 hp?  The 80 hp weighs 122.0 lbs, the 100 124.2 lb, and the mount, exhaust, alternator, cooling system are the same.  

#BarryStott The Stemme has been my dream aircraft since the first review I saw of the SV 10 shortly after it was available in the US.  Others have been quite vocal about it being a maintenance nightmare.  I have a repairman maintenance certificate for the RV-12 with Rotax 912ULS, and it is very low maintenance.  I have been concerned that in addition to a high entry fee to get into a Stemme, I'd be saddled with high maintenance costs.

#Chasers03 I have had conversations with a Phoenix owner in S Carolina and I am very impressed with his report.  It is the only one I have found for sale in the US.  Jim Lee told me the wait is now "3 years, or longer."  I may yet increase our budget to acquire the one for sale.

#Todd I started this journey convinced I wanted a Pispstrel MX or Sinus Flex.  I'm 6'4" +/- and I recently flew out to rural NE to sit in an older 13.5m Sinus.  My head fits between the upper bars, but I'd worry about serious knocks in turbulence. The seat and position felt very comfortable, though.

I have been looking at places to train in the different aircraft, figuring it should be specific to the model.  Please send any positive or negative reviews to me at bud.shaw@gmail.com

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mikeschumann

The 100hp Rotax in my Phoenix has been a great engine.  I’m not a Rotax expert, but mechanically I think the 80hp and 100hp engines are very similar. The biggest difference is that the 100hp engine requires 91+ octane fuel, while the 80hp can use 87 octane.

Rotax recommends using unleaded fuel instead of 100LL.  You can use 100LL, but you need to double your oil change frequency.  In some parts of the country (particularly FL) ethanol free 91 octane MOGAS is getting hard to find.  Except for the few airports selling UL94 fuel, the maximum octane ethanol free fuel you can find anywhere in FL (airports or gas stations) is 90 octane.

Rotax engines can use fuel with 10% ethanol.  However some aircraft have wet wing tanks where the ethanol can attack to carbon fiber resins in the wings.  If your aircraft has fuel tanks and a fuel system that is designed for MOGAS with ethanol, none of this is an issue.

To get around this problem in my Phoenix (which has wet wing tanks), while in FL, I burn a mix of 90% REC 90 fuel with 10% 100LL.

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TomSw1ft

I have full confidence in the Rotax 4-cycle engines.  I took the Rainbow Aviation course the year we acquired our RV-12 and have done all of the required inspections and permitted maintenance procedures and Service Bulletin work.  We have good access to lead-free, alcohol-free MOGAS at 91 and 87 octane, but ,most of the ETOH-free is 91 octane.  On one fly-out with our EAA chapter, I had to refuel and filled it with 100LL.  I then decreased the oil change interval to 25 hours for that cycle, which I reached about 5 hours later.   For some reason, ETOH-free MOGAS has become more available here in the past two years with Shell and BP selling it everywhere, and a few lesser vendors as well.

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Todd

Here are a few numbers that might be helpful with my 2017 Sinus Max. I never purchased the short tips and never found any reason to want them. With the tips off the span is just a bit over 39 feet. I am 6’ 2” and am comfortable with many flights over 5 hours.  My Empty Weight is 784# with useful load 538#.  I have the Ballistic Chute, 48ah of Batteries and ADS-B.  With full fuel of 24.5g that leaves 391#.  I think the most fuel I’ve had onboard was 22 gallons.  With 23 gallons you can have 50# luggage and 350# for pilot and passenger.  For local soaring flights I rarely have more than 10g fuel onboard. 
I’ve made 4 Round trips recently from KPMP to KSGJ of 462nm.  The fuel burns were between 14.1 and 15.6g (average 14.9g) for a bit over 31 nmpg.  These flights averaged 2.67gph and include weather deviations and gliding at the end of each flight. 
I use 100% Rec 90 fuel (Ethanol free unleaded) that I get from my local Shell station with current price $2.37/g.  
 

CB905C66-F40F-4D71-92F2-93A340980AB6.png

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Ximango97

I own Ximango S/N 97 since early 1999. 80 hp Rotax. My Ximango logbook shows almost 2000 hrs total with 1500 hours engine time. I 'drove' it four times from my home base near Philadelphia, PA out West to Nevada, Arizona or California. Several trips to Oshkosh and Florida and other multi day adventures. I never had to delay a trip for a unplanned maintenance issue. I cruise at 105 kts indicated near sea level. At 8000 to 10000 ft indicated airspeed is still around 95 - 100 kts with full throttle. This is better than 110kts TAS. I occasionally did short (`100 sm)  soaring cross country flights. You need a really good day. In my Kestrel (18m, flaps, L/D 43) I could have made 300 sm or more.  The glide ratio number does not the the whole performance story. at speeds > 70 kts. sink rate increases more than in a glider of similar L/D. The Ximango handles reasonable well in thermals. I most of the time could keep up with my club's Blanik or Grob-103 two seaters. I own winglets but hardly use them.  The seats are very comfortable. Never had problems even on days with 10+ hours fight time. The ailerons get very stiff at cruise speeds. My arm gets really tired after 10 hours. The Ximango is my favorite aircraft with an engine. Still prefer the one's without. I would not use it as primary trainer. Recommend to have at least 20 hours in a modern glass glider or extensive tail wheel experience. The most challenging operation is cross wind take-off. Cross wind landings are more manageble if you know how to work the very effective spoilers.

I have some exposure to other motorgliders in your list. Keep in mind my bias towards Ximango when I compare them.

Ximango S (100 hp): I did ferry one from Puerto Allegre, Brasil to Florida. 4 days with 3 legs each. What an exiting trip. A little faster than my 80hp. It had the new ailerons which improve handling at cruise speed significantly. Need to watch engine temperatures and cowl flap setting. Not as forgiving as mine. Otherwise identical.

Turbo Ximango (115 hp turbocharged, constant speed prop): Did some flight instruction for new owners who bought it used. Performance near sea level seemed to be sluggish compared to my aspirated 80 hp. Could have been a maintenance issue? Otherwise same characteristics as mine.

Grob 109B: Flew it in Germany in the years 1975 -1998. Easy to fly. Robust. Was used in a glider club for short cross county flights navigation training, not so much as a primary trainer. I never turned off the engine. Probably only a few in the club tied soaring in it. Be aware the engine is base on the old VW. Spare parts might be no longer available. Wings fold back to a dolly mounted on the tail. Wings are heavy. Folding can be done by a single strong person. Do not try to unfold it by yourself. That takes at least 2, better 3 people.One with strength. One with brains.

Diamond HK36: Kown a 'Dimona' in Germany. 15 m wing span. Turbo Rotax with constant speed prop. I liked its handling. Very responsive in rolls. Again much more a light power plane than a glider. I do not remember ever trying to soar it. Wing does not fold. Needs a 50 ft wide hangar door

You are probably right that too many motorgliders are underused. I personally would stay away from any aircraft that was sitting unused for 2 years or more. Of coarse unless you are interested in tinkering more than in flying.

I do not know anybody able to handle both the Rotax engine and a fiberglass air frame. If you find one, let me know.

Have the aircraft inspected very thoroughly. Do a new weight and balance. If there are changes from the previous one, suspect undocumented repairs. Check all logbooks and the previous owner(s).

If you have more questions, lets use the phone.

Good luck

 

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Lert

Hi--

I have (or hope I still have--it's in a hangar in Healdsburg, California, currently threatened by wildfires) a 1985 Valentin Taifun 17E which was originally imported to the US by Carroll Shelby (of Ford Cobra / Mustang fame) after he had a heart transplant and lost his medical.

At the time (just prior to the introduction of the Stemme) it was the most sophisticated TMG available--retractable gear, camber-changing flaps (including reflex for better, or at least less worse, performance at higher speeds), etc.  It originally came with an 80hp Limbach (VW derivative) and Hoffman three-position prop (takeoff, cruise, feather). Shelby put a 93-hp Sauer (also VW derivative) in this one; I have, but have not yet installed, an MT constant-speed featherable electric one I bought from a pranged Taifun in Germany. I fell in love with the type when my best friend from high school (in Switzerland) and I flew his from Germany to Nepal in 1985 for a meteorological research expedition in the Himalayas. (Unfortunately, the hoped-for giant wave didn't materialize, and our research flights required at least an idling engine to provide electric power for all the scientific equipment). We averaged a bit over 100 knots on the nine-day approximately 6000-nm flight from Germany to Nepal, via Italy, Greece, Egypt, Saudi Arabia, Oman, Pakistan, and India.

For what it's worth, I don't fly mine nearly as often as I'd like to. It shares a hangar, with wings folded to eight-foot width, with a single-engine airplane, and its vaunted one-person wing rigging system worked a lot better when both it and I (I'm in my 70s) were new. The sliding tubes for the wing root (on which those for the Stemme's outer wing panels are based) have sagged over the years, so rigging now requires either a motivated helper or--in the future--a sophisticated rigging aid, which I'm in the process of designing. I might add that while almost all of the 20 or so Taifuns in the US are type certificated, mine happens to be experimental (because of the different engine), and I fully intend to keep it that way, since I can work on it myself and get its annual "condition inspection" signed off by an A&P.

It's a nice low-cost cross-country transport, with a roomy and comfortable cockpit, adequate baggage compartment, and nice handling, if a bit heavy above 100 knots.  It handles much more nicely at soaring speeds, but with a claimed 28:1 glide ratio (when new, with nice, smooth wings...which mine aren't anymore), and a gross weight of 1875 lbs--275 lbs more than a Cessna 150, with 100 hp!--its climb, whether thermalling or powered on a warm day, can be underwhelming.

Despite my friend Barry's enthusiasm for his Stemme--in which I happen to be checked out--I don't know that I'd buy one, even if I had the means. I might add that I'm very familiar with the type--as I'm a German speaker, I was hired by the factory to provide the English-language flight and maintenance manuals for it and its successor, the S12.  They're magnificent pieces of engineering, but very complex mechanically, and to work on the engine, you'd ideally want an arm about five feet long, with a wrist every foot or so, and the final wrist should be able to rotate 360 degrees...and ratchet. A point Barry didn't mention is that the Stemme's folding propeller, while an engineering tour de force, requires overhaul every 200 hours of power-on operation  (or based on calendar time), at a cost on the order of $10000; there are various other "unique to the S10" bits (driveshaft, prop gearbox) that also have mandatory inspection and/or overhaul requirements, and since this isn't an LSA, they have to be done by a certificated mechanic.  AFAIK, there's exactly one factory-authorized shop in the USA that can do the props, with commensurately long lead times.

In terms of performance, it compares well with something like a Duo Discus (which I happen to love, based on several fabulous weeks flying one in the South Island of New Zealand). Compared to the Duo, however--which you can fly like a helicopter, resting your wrist on your thigh and just flying with your fingertips--I'd have to describe the Stemme's handling  as "truckulent," particularly in roll.

I also have some experience in the Ximango--basically a Rene Fournier design, the RF-10. Fournier pioneered the idea of "motorgliders" altogether with his single-place RF-3, which, among other things, has crossed the Atlantic both ways.  It's nice enough--rather similar to a taildragger Taifun, with less baggage room. Its wings fold about halfway out, which is handy for narrow taxiways, since it can be taxied with them folded (same goes for the Stemme). I've had no trouble spreading the wings of either type, alone. Hooking up the ailerons on the Stemme can be a bit fiddly (and the consequences of doing it wrong dire); on the Ximango, it's automatic. I'd be careful spreading the wings of either type if it's windy, particularly those of the Ximango.  (FWIW, the Taifun's flaps, ailerons, and dive brakes all connect automatically during its wing-spreading procedure).

Although I've only flown one a couple of times, I think if I were to be shopping for a touring motorglider now, I'd strongly consider the Phoenix--decent soaring performance, very pleasant flying qualities, reasonably roomy cockpit, ballistic parachute, removable wingtips (for both hangaring and to be able to fly faster as an airplane if you want to go somewhere, rather than soar), and as an S-LSA a lot more amenable to owner maintenance. I haven't flown the Taurus, either electric or two-stroke...although as a former owner of ultralights and a veteran of engine failures in the BD-5 (long story), I tend to shy away from the latter. I believe the Czech designer of the Phoenix is flying an electric one with retractable landing gear; I don't know if, or when, that might ever come to the USA.  Dr. Reiner Stemme is developing a 20-meter electric follow-on to the S10/12 called the "Elfin," with approximate Duo Discus performance, but at the moment I don't know whether (a) the prototype has flown yet, or (b) whether financing for production has been secured. It's based on a very interesting concept: sufficient battery capacity for takeoff and climb, with maybe an hour of "get to an airport rather than land out" reserve power at best L/D speed. For longer and faster ferry flights, it'll ship a detachable "power pod" under one wing, with a little rotary engine, generator, and fuel tank, that should provide about 600nm range at 100 knots, while simultaneously recharging the big bite of battery power one would have taken for takeoff and climb.  It looks like an ideal solution, but it won't be cheap if and when it gets into production.

Drop me a line (peter.s.lert@gmail.com) if I can be of further help, and good luck--

 

psl

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Eric Greenwell

There is some serious misinformation in DermotMcD's posting that I'd like to respond to (my remarks are in blue😞

I don't think that even the Stemme does better than 95 knots cruise and if 110+ is really what you are looking for, then nothing much which glides is going to do the job." The Stemme cruises at 130 knots! My Phoenix cruises at 110kts.

SLGs, pretty much all of them, are really noisy vibrate and 95% don't cruise with power on. Perhaps only the Schleicher rotary cruises with power on but then at low speeds and big fuel consumption. Almost all SLGs have two strokes and/or short motor lives… 400 hours TBO and few motors actually make those hours. You don't buy an SLG for a touring motorglider (Stemme excepted)! SLG's don't cruise in normal operation, but only rarely when a "self-retrieve" is needed, so the propeller is optimized for climbing. For that reason, a 400 hour TBO is a LLLOOOONNNNGGGG time for an SLG motor; for example, my SLG has 200 engine hours and 4000 flight hours. That's a 20:1 ratio of engine time to flight time, typical of a SLG, and it took me 25 years to get those hours.

The old-school certified types like the Ximango and Grob and the newer LSA types. Without looking up the numbers, a Ximango has got an MTOW of 850 kgs while the LSA types are about 450 kgs less. Quite a lot of the extra weight of say a Ximango compared with a Lambada seems to go into the structure. Yes, plenty of it does go into the structure, because it's a fiberglass instead of the lighter, stronger, carbon fiber of the modern LSAs. It also goes into things like the retractable gear and large wings needed to support fiberglass and gear weight. The LSA MTOW is 600kg, or 250kg less. My Phoenix has a 420 lb passenger+baggage payload, compared to a Ximango's 386lbs, both at full fuel (24 gallon).

In rowdy air, even on low finals, the Ximango is very stable and controllable. I doubt you could say the same with something 400 kg lighter. As I said they are 250kg lighter, but because of the smaller wings, the wing loadings are similar, so they are just as controllable - perhaps more so, as the shorter wings give them quicker handling.

I'm staggered at what a Ximango will absorb. An owner I know said the "Ximango is like a jeep, it'll go anywhere.' I'm not sure about the LSA ratings but Ximangos etc are certified to utility category - 5.4 G +. "Like a Jeep"? It's not a back country, land in a pasture kind of plane, especially with it's 550 extra pounds but the same 80-100 hp as an LSA. The LSA load factors are +4/-2 G, which has proven sufficient for 15+ years. These are are operating limits; the "fail" limit is much higher for both aircraft.

There was a lot of talk about ballistic chutes in sailplanes 10-15 years ago. You don't hear about this these days. That's because most sailplanes are motorgliders, and the motor, mast, propeller, etc occupy the space the ballistic chute would use; even so, more sailplanes (including motorgliders) are offered with ballistic chutes now than 10 years ago.

A proper sailplane is so slippery that if something breaks, it's accelerates really fast so the opening shock on a parachute is high and you need a lot of altitude to make it work. The opening shock is easy to mitigate, and less that 500' is needed. The pilot can pull the deployment handle and have the parachuted deployed in a few seconds; it takes much longer for a pilot to jettison the canopy, release his belts, get out (if the g forces even allow it), and finally open his parachute - at least a 1000' is a common number given for a successful bailout.

Then the glider tends to descend in a nose down attitude which isn't great. Actually, it's fine, because the cockpit (and landing gear in fixed gear aircraft) is designed to protect the pilot during the impact.

 Another issue is the fact that most modern gliders are built light and strong to give a light wing loading which can be increased enormously with water ballast. Add a ballistic parachute and you lose this advantage. The ballistic parachute has no effect on the use of water ballast, which is carried in the wings. The net weight of a ballistic system (subtracting the weight of the personal parachute the pilot no longer needs) is about  10-15 lbs, an insignificant difference.

Before I bought a Ximango, I spoke to a lot of owners, all of whom sung the praises of the 80 HP Rotax over the 100 hp… when fitted to the Ximango. Folks, DON'T buy a Ximango with the 80 HP engine! You will find it very limiting, in performance and with lower payload than the 100hp version. Your takeoff performance suffers, you'd be very limited in the payload you could carry, and the density altitudes you could handle. Think about it: An LSA like the Phoenix or Pipistriel Sinus at a 1320lb MTOW is a great performer with a 100hp 912, but what would an 1775lb (the MTOW for the 80hp) Ximange be with at 20% less HP and 35% more weight? Ouch!

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TomSw1ft

I appreciate your clarifications.  I become skeptical when someone has strong biases with little apparent underlying supporting information.  If I had unlimited resources (or a lot more than I do) it would be fun to fly a Stemme  and pay the best ever mechanics to care for it while I return to my yacht.  

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Tim Blofeld

Hi Bud,

I've been doing the same exercise for about four years! Came down to a used S-10 or Phoenix. Both great but neither perfect. Perfection for me, as mentioned above, is Reiner Stemme's new design, the Elfin. It is the only one that checks every box, and the design keeps getting better (lighter wing folding system with reduced span to 33', increased battery range, unlockable steerable tailwheel to act a dolly on the ground, folding step on the undercarriage for easier access). 50:1 with smooth, quiet, reliable electric power. The downside is, none have been built yet! I finally pulled the trigger in October 2018 when the plan was to get it to Oshkosh last year. Delivery now promised "in the spring" (I'm assuming 2021)! Yes, it's expensive, but in the ballpark for the category and maintenance will be negligible. Put solar on the hangar roof and fuel cost will be zero. Rent a range-extender if/when you need one. Get a third partner, refi at 2.8%, discount the maintenance and fuel (two hours of electric power costs less than a dollar) and remember, you only live once! The website is out of date but you get the idea. http://www.reinerstemme.aero  Happy to discuss further if you want more detail. timblofeld@gmail.com.

All the best

Tim

 

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Todd

Hi Tim,

l’ve been following the Elfin 20.ex very closely and an looking at a Sept 2022 delivery date for myself.  I’ve helped a bit with the financing and have been emailing back and forth with Reiner quite a bit earlier this year.  I’ve let Reiner know that easy ground maneuvering and set up with just one (older) person is important but I was thinking about lifting the tail to install a dolly and tow bar (which would need to be carried onboard).  I hadn’t heard anything about the tailwheel being able to swivel fully and all diagrams I’ve seen for the retractable tailwheel don’t seen to show that.  Please tell me more!  Also the folding step is a great addition that I hadn’t heard of.  Last I heard the prototype would fly by the end of this year but I don’t know how much COVID-19 has set them back.  Maybe you can rent me your Range Extender as I don’t expect anyone will have one for rent at my local airport!  I believe that is a $50000+ option.

-Todd

8058CBFE-AF50-4736-B763-C4052B18A326.png

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Tim Blofeld

Hi Todd,

Great to hear from a fellow Elfin believer! Yes, first flight planned 4th quarter 2020 and financing seems to be lined up. One advantage of delayed production is additional design improvements. Recently heard about the new tweaks via email from Reiner. I didn't order a range extender either but the idea is to have one or two available in the US to ship as required to wherever they need to be. Rent by the week plus hourly run time. I'm investigating the feasibility of flying from Berlin to Oshkosh next year on the assumption the company would lend me one to cross the North Atlantic and Greenland for marketing purposes! 

Cheers

Tim

 

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DermotMcD

HA,

Quote

 I become skeptical when someone has strong biases with little apparent underlying supporting information.

Well, I don't think the comments I wrote were that biased or even that strong, and as per usual, space and time limits supplying support info. You asked for thoughts, and that's what I gave you. I felt that though your shopping list had most of the right points, some were self-exclusive and I tried (in brief) to point out those which were. If you can get a Phoenix for under $120,000, then maybe that's your aircraft but it appears that may not be possible. 

You asked about TMG and SLGs. My reply about SLGs not being useful for cruising stands. SLGs are far better sailplanes and far worse motor planes than a TMG. It may well be that you would have the most fun with a DG 500M but maybe you do want to motor more often than glide.

I said the Stemme appeared to be a great performer. In the time I have spent flying alongside one, it performed as well as a well enough flown ASH 25 and ASH 26. If you're handy with a spanner and have a ticket, go for it!  I have never owned one but I have flown extensively with people who have owned them… and even they report high maintenance time and expenses, difficulty getting service and in reselling the glider. Others have supported this in the postings above.

I own a Ximango and an SLG. My comments on the Ximango were my own experience and the experience of other owners who I spoke to pre-purchase. The "Jeep" comment is the opinion of one owner, not mine. The fact that the 80 HP Rotax is a jewel of an engine is an opinion shared by a lot of Rotax owners. To me, the idea of adding another 20 HP to an airframe and wing section like the Ximango is a bit silly. All that extra power for what? 5 knots? Fine if a 100 HP version is available but I don't lose any sleep over the 80 HP in mine.

The Ximango has carbon spars though the rest is FRP.  I made no mention of a Phoenix because I have never seen one.

I've flown with a Sinus and seen a crashed Lambada closely to know which I think is the strongest and best in rowdy air. The Sinus locally has a MTOW of 450 kg and the Ximango, like most traditional 2 place certified gliders, 850 kg. "The LSA load factors are +4/-2 G, which has proven sufficient for 15+ years. " It may well be so, but it's not the same as the certified utility rating of +5.3 and - 2.65 is it?  I know which I prefer in a second hand glider.

Unless something changed while I was not looking, the MTOW of your standard 2 place German glider is still 850 kg. Probably this is an agreed thing rather than legal. If you add a 75 kg parachute as well as a 75 kg motor to the fuselage, you reduce the available amount of water ballast by 150 litres… and you reduce the available range of wing loadings. Since many German gliders are made and sold by factories centred on competition, the water ballast equation is important and buyers chose the motor.

Ballistic parachute systems are a great idea but find me a German manufacturer of sailplanes who has fitted one? I wasn't talking about parachutes in LSA aircraft since I have no experience of those but my comments were prefaced with "sailplane' througout.

Tests on sailplanes were done extensively a decade or more ago and the only development has been DG's NOAH system which anyone who wants to bail out of a sailplane should have fitted. All the tests done at the time showed a nose down descent angle under parachute with a rate of descent which it was claimed, would have resulted in some injury. Since I was talking about sailplanes, there's no landing gear to absorb the shock and in any case, the angle (about 60º) was extreme enough that no modern landing gear would touch the ground until the nose cone (including the pilot's legs) had collapsed.

So-called safety cockpits in sailplanes are a great idea (my glider has one) but they're not a Formula 1 car cockpit which can survive a crash of well over 10G (see Lewis Hamilton's escape from a 30G crash) and these safety cockpits have had very limited testing… and that mostly by users rather than the factories. Pay the right amount of money and you can have a proper safety cockpit… apparently Aston Martin's exceed F1 specs, but in your average glider? It's just a bit better than the eggshell which was fitted in earlier years. As and article says on the DG  website, safety doesn't sell gliders.

With any parachute system, it's irrelevant how long it takes to open the chute in seconds. What counts is distance. To mitigate the opening shock of a parachute attached to an 850 kg glider accelerating towards and beyond VMG, you stage the opening and/or use a smaller parachute all of which increases the opening distance. My recollection of the figures I saw was that the opening distance was a lot longer than if the pilot was able to bail out… perhaps 3 times.

So while I would like a ballistic chute, if it's a choice between that and an engine, I'll take the engine because I can use it every day and a NOAH system which I hope I won't need to use.

Somewhere around, I do have the original OSTIV articles for the ballistic parachute stuff above, but I don't have all my records with me, so treat that as opinion if you will.

I'm sure there are better motor gliders than the Ximango but either I have not seen one or cannot afford one. Perhaps at $120,000 you can't either. If you have that much to spend, you could do worse than a Ximango. Or a DG 500. It's always going to be a compromise. They're my thoughts!

D

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TomSw1ft

I'm very sorry @DermotMcD that my comment offended you.  I did not intend to do so.  I was actually trying to respond to the post by Lert, not Eric Green (although Eric's was full of additional information).  Your post was very informative, and you have inspired me to reconsider my options, expanding them for me.  

This is not an excuse; I was wrong to have responded in such a nonspecific way. But, these days I find my antennae for statements of apparent fact that seem to go against my prior understanding.  I yearn for evidence.  I am a former physician and medical journal founder and editor who took pride in sending manuscripts back to authors with a demand for substantiating data.  In this time of COVID-19, I've been surprised by just how many doctors, who ought to have learned scientific method, advocating utter bullshit, like treatments that have not only been shown by numerous well-controlled trials to be of no benefit, but also dangerous.   

My dream ship has always been a Stemme.  That emotional response has never been based on any actual experience — just good marketing.  Not until the accumulation of reports about their maintenance headaches did the real world experience of some others become part of my understanding.  Is the 200-hour maintenance actually a $10,000 hit? I don't know, but I did not pursue the validity of Lert's claim because the Stemme just isn't on my list right now.

I am really enjoying the information that everyone is providing.  Opinions are, to say the least, spirited. Data runs through out the postings, but so does personal bias.  I appreciate both.  I just don't take everything as necessarily relevant or strictly factual.  

The last thing I wanted to do by admitting to some skepticism of some of the postings was turn any one off.  

 

 

 

 

Edited by TomSw1ft

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Eric Greenwell

I see I need to "clarify" my own posting 🙂

The Ximango is a decent airplane and a decent glider. The choice of engine, however, should not hinge on any perceived "jewelness" of the 80 hp 912, which is mechanically identical to the 100 hp engine, but with a smaller bore. Both versions have excellent reputations, both have sold 10,000+, and both have the same 2000 hr TBO (current versions - older versions may differ). I would base the engine choice on the density altitudes I expected to fly, and how often I flew pilot-only/partial fuel and no baggage, or pilot w/passenger/full fuel and baggage. Putting it another way:

  • A Florida pilot that will do mostly soaring alone - either engine would be great
  • A Denver pilot that often travels with a passenger, baggage, and full fuel - the 100 hp engine would be much appreciated

While not pertinent to the Ximango, as an airframe rescue parachute is uncommon outside the LSA category, I think there is an underappreciated value to it: my wife is willing to fly in our Phoenix for two reasons:

  1. She knows it can easily glide to an airport or other safe landing place if the engine quits
  2. She knows it can parachute down safely if things go really bad - that makes her feel much more secure (I also like it for that reason, and also because it's easier to get in and more comfortable to sit without a parachute).

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