jetsmell

Is there a big difference in performance between the two given the same plane? Even with a folding prop?

soarrich

My Feedback: (98)

The biggest difference is you'll fly the electric more.

JWHITACRE

Hmmmm....this one could get ugly. It's like the glow vs electric debate in a way but I'll put in my $.02.
Given the same airframe is used the major difference would be the wing loading. Obviously the one carrying the electric setup will be heavier but sometimes that isn't necessarily a bad thing(think built in ballast). The nice thing about an electric rig is the ability to go back up without having to land. Now on a day with very light lift I prefer a pure sailplane simply due to the lighter wing loading so I can work what lift is out there to the fullest.
Basically I think it comes down to preference AND where you fly. If you don't have access to a field big enough for a winch or hi start then electric would be the only option.
No matter what have as much fun with whatever you are flying, that's what the hobby is all about

BMatthews

There's no doubt that even with a folding prop that there's more drag on the nose of the plane than with a clean pure glider. But really it only becomes a big issue if you're planning on flying at higher speeds much or all of the time. At thermaling speeds or during "best L/D" cruising speeds the added drag of a folded prop isn't a big handicap. And such planes can still boogie along at need when pushed with a couple of clicks of down trim. Maybe not as efficiently as a pure glider but pretty darn well.

aeajr

My Feedback: (2)

Istarted flying with small electric airplanes. Now Ido 90% of my flying on pure gliders.

The penalty associated with electric gliders is weight and drag.

However,major advances in battery and motor technology have reduced the weight portion by a lot. If carefully designed and installed the weight penalty of an electric glider can be less than 20% and in some cases the pure and electric gliders can be very close in weight.

The extra drag imposed by the prop has not gone away but at the speeds flown by the typical TD glider this drag should not be so great as to be a major issue for most sport pilots. And if you are flying in competition, everyone else has the same drag.

I have 3 electric gliders. Of those my Radian gets the most air time.

However 80% of my soaring time is on pure gliders flow off winches. I love the challenge of pure gliders. They are sleeker and frankly I love the thrill of the launch. I also launch them with a hi-start and now a Onewinch human powered winch.

I compete in TD using winch or discus launched gliders. Idon't compete inelectric gliders.

For slope soaring, again, I often recommend a first time slope pilot start off with an electric glider. The motor serves as a safety feature so that, if the new slope pilot gets in trouble he can get back to the landing area. A newbie on a pure glider is more likely to land out which can be a real ugly issue when slope soaring.

I am a member of a glider club and I start all new pilots, that Iteach, on e-gliders. They make learning easier as you spend less time launcing and more time flying. But I encourage them to try pure gliders as well. In my mind pure gliders are the more challengin and therefore a next step from electric gliders for these new pilots. Most eventually add pure gliders to their fleet.

The new, light weight electric gliders have brought a lot of people into soaring who would not or can not enjoy the fun of pure gliders due to flying space or physical limitations. For them e-gliders may be their only way of enjoying the thrill and beauty of soaring.

tobuy3003

The difference is so small youll never notice it. If you dont know about lift and sink cycles then both types will sink. I really doubt youll learn to soar with an electric. This is whatI have seen personally by watching others who sink like a rock from using electrics when competing against others who learned with nons. Ihave tried electric with all types of ways to rig the motor and it never feels like a pure glider. Iended up selling the elec ones due to the lack of total desire, but then I know how to soar quite well.

The weight wont matter unless its just after winter, mild and humid. Thats what long skinny wings are good for- handling weight.

aeajr

My Feedback: (2)

I have to say I prefer the pure gliders too.  

da Rock

This is a somewhat unclear comparison.

Are you interested in comparing electric gliders with fuel engined or with pure gliders or both? I would guess you don't want fuel engined since there really aren't any.

As for electric versus pure................

Some people don't have a choice. In the last 5 years of looking, I haven't found a single site within an hours drive where a high start or winch could be setup. Got no idea if there are any sites beyond that might, but every potential one I've heard about got looked at by satellite and was covered in trees. So electric is the winner by default. There actually is one site but it belongs to an R/C club that's active all week long. When the 'chute takes the cord downwind and fouls the runway or drapes over the cars in the parking lot, it's time to roll up the high start. When it's landing on or across the runway, time to roll it up. Hand launch just doesn't get it. So electric does. Electric gliders fly at all the R/C clubs around with no conflicts of any kind.

Better believe I'd prefer pure gliders, but unfortunately the geography often controls the choice.

aeajr

My Feedback: (2)

Thanks heaven for e-gliders.  The soaring pilot's friend. 

tobuy3003

Ihave recently found many places to fly using Google earth and also many folks use parks since its motorless or community college fields.

The long line for a high start is the old way. With most any glider and especially a molded one, you simply lay out 50 ft of doubled rubber or strong exercise tubing with 80 foot of mono line and no chute. You get a zoomie at the top. This works even for a Bird of Time. You dont need a super high launch. You only need careful timing. When there is lift there is lift.

There is another way to launch using only 10 foot of line for fast gliders.

Many power rc club sites are not used in the hot summer at noon. You and your buddies will be the only one there...

Using the short start here works just fine. Its a small about of tubing and a short line without a chute. Long highstarts are a thing that was needed 30 years ago. - Thats my guess. Ihavent seen the need for one around here and how else do DLGs work? They dont need a 250 yard highstart.

Louis9624

Here's a way to look at electric, the decision to fly your electric glider starts wherever you are - in your home, in your car, anywhere. The decision to fly your slope glider starts at the hill or the slope, because it depends on the weather.

aeajr

My Feedback: (2)

Not quite sure Iagree with this.

The decison to fly your pure or electricglider begins in your home or your car or anywhere you are. No wind required but Ithink you would agree that too much wind will hault you from luanching your electric or your pure glider.

The decision tofly your slope glider begins in your home or your car oranywhere you can hear a weather report. If youhave the right wind direction an enough speed,it is timeto go slope soaring.

Louis9624

aeajr, you're right, it is a better explaination of what I was trying to say.

OzMo

My Feedback: (3)

HI,
The electrics such as the Radian sure give more oportunity to find thermals. Their performance for the buck is exceptional.
This season flying Radians (I think our club is up to 15) more people have developed skills finding lift and gaining overall glider skill than ever before.
Still the satifaction of finding lift and staying up with a pure glider is unbeatable IMHO.

Cloudy Dave

This is my first post ever, anywhere, so: "Hi there from New Zealand". I'm hoping to completea vintage Dumas 101" Hi-Pro soarer I started over 25 years ago and I'm planning to modify it to optionally take a small inboard electric ducted fan, the idea being: low power, low weight, low drag.Folding props give me the creeps and they weigh in about the same as a fan but with more drag and not very good looks. Any comments on this welcomed. Incidentally, has anyone access to the Hi-Pro plans and instructions - mine have gone AWOL?[Sales at Dumashave never heard of theirown sailplane kit and said flatly: "not one of our kits"!!!Hmmm!

papermache

My Feedback: (35)

It comes down to this:
There are advantages and disadvantages to both setups. You have to figure out which suits you the best. In the end it's your money and your time, so enjoy yourself whichever you choose. You're certainly not going to change anybody's mind by writing in a forum.

papermache

Cloudy Dave

aeajr

My Feedback: (2)

Ducted fans are notoriously noisy, not especially efficient and typically don't do well at low flight speeds, so they are not commonly used on sailplanes, inboard, outboard or on pylon.

If you put it down the center like a fighter get you expand the fuselage and create drag down the tunnel when the motor is off.

Other than the oddity factor, I can't really think of why I would want a ducted fan on a sailplane. Propellers are far more efficient, much quieter, and the drag induced by having them on the nose is not that much at the speeds we fly while thermal soaring.

Cloudy Dave

Thanks for that. I had thought that for low-power boosting the noise would be far less than in the usual applications of high wing loading and sustained flight and being only in sporadic use the noise would not be an issue?? The nose would remain smooth and closed except for a possible ultra-small camera port. Intakes would be faired into either side of the fuse andservo shuttered when motor off to clean up when gliding.More comments please . . .