RES vs. Full House - Which is better for Thermal Duration Soaring?

[Ed Anderson]

This is all about opinion, so opinions are welcome.  None are wrong and none are completely right.  They are, after all, opinions.

 

Since we are talking R/E as art of RES, and we have gotten into e-gliders, is the Parkzone Radian popular in the UK?   It seems to be running wild in the US.  New pilots are flying them, Instructors are using them to teach an many experienced pilots are buying them as "toss in the car" models.

 

Are they seeing much interest in the UK?

 

 

[Tom Satinet]

no not really, more the mpx easy glider. well that i have seen anyway. 

[Erfolg]

Ed

 

In the UK market there are many similar ARTF models by other manufacturers, probably Multiplex leading the market. I have seen a number of the type in electric only clubs, mainly used as trainers, something like a latter day "Gentle Lady", with better performance. The best foamies i see on a regular basis is the MXL Cularis, truly surprising as a model.

 

A trend I have noted within the club I am a member of, is that lower wind speeds being much preferred. The reason being we now longer bungee, but essentially 95% electric. Where calm days were cursed, and ballast often being used. now we see a +15mph wind and most climb back into their cars, me included.

 

Another trend which I have observed, as a returnee after  +20 years, is that my club no longer runs or participates in competitions as a club group. When I was the CD I could count on 60-80 competitors at each event, which I seem to remember there being a minimum of 2 per year (BARCS league). Within the club we held the summer evening competitions each Friday, plus a number of other competitive events. Times seem to have changed, me with them.

 

I suspect that some clubs are still relatively strong, though I suspect with no real evidence, that the numbers are well down.

 

Yet I am very much encouraged that the 200m motor cut of may bring some back, may be some new people?. Though looking at a 2m mouldie today, by some Czech manufacturer, whose glide performance was outstanding, that the shear cost could well put odf many older retired modelers. We Have three 3.5m Czech type "Bubble Dancer" type models in the club, this 2m model has the potential beating of them in a 6mph wind, it even has room for ballast if needed (I am not sure where). They all have the full accompaniment of bells whistles, and switches to flick for all situations pre-programmed. What is a little surprising is how big a BD type looks at 200m high and how small a 2m looks at cut of. I cannot guesshow high they were getting in 30 seconds, but suspect it was much, much, higher. It really is a thermal gliding competition now.

 

Erfolg

 

Erfolg

[Tom Satinet]

it surprises me this thing about wind. if you read the forums it seems that a lot of power fliers pack up at about 10 - 15mph. but it seems to me as a slope soarer that the wind is over 10mph quite a lot of the times. Okay it tends to be windier up the face of the hill, but even so.......?  People must not be able to fly half the time. It's a fairly windy country and nothing is going to change that.

[Tom Foreman]

Your right Tom, I was down the club recently and it was blowing about 25mph, people turned up but didn't bother unloading there cars, I had brought a MPX Blizzard and amazed them all when I got it out to go and fly it. It zipped round the sky quite nicely and slowed up well for landing with all that headwind, a lot easier than when its up the slope and trying to land when its in lift

 

Tom

[Tom Satinet]

yeah Tom exactly. I don't understand why guys like that don't have model like a blizzard for when it's windy. okay if your passion is 3d or WW1 scale planes or something it won't be what you really enjoy, but it has got to be better than not flying at all.  Unless I am missing something. 

 

Even now as I type it's 10mph on the flat and it's quite a nice and calm day. 

[Ed Anderson]

HOW WE FEEL ABOUT WIND SPEEDS DEPENDS ON THE KIND OF FLYING

 

Clearly there is a HUGE difference between 15 mph winds at a slope site and 15 mph winds on a flat field and we need to be specific as to which we are discussing.

 

Flat Field - At our club field, which is a flat field of 800X1600.  We have an additional 2000 feet of woods we cand fly owver on 3 sides.   At that field, when the wind gets over 10 mph many of my club's pilots won't fly.  VERY few will fly over 15 mph unless it is a major contest.  We had a regional contest once where the winds were over 20 mph, gusting to 30, but we flew! 

 

Slope Soaring - Most of my slope sites are not really flyable under about 6 mph and then only with very light planes.   At the slope 15 mph is great and 20 is outstanding!

 

I have only once had winds over 20 mph at one of my slope sites on a day when the wind was in the right direction AND I was available to fly.   The lift was amazing!   The site was a beach and the sand was blowing up into our faces making it hard to see.   I had to pull out goggles.    I would LOVE to do that again!

[Tom Satinet]

20 is not strong for sloping.

 

if you tea comes out of your mug you know it's a good blow!  

 

 

I'm not saying it's the same. I'm just if it were me I would have at least one model that could handle a blow. I'm talking non glider flying here. 

[Myron Beaumont]

Ed

I think that Timbo will shudder at the thought of 20 odd mph being a bit iffy . It's normally a calmish day in the UK  Your "6 mph " on a slope rarely exists over here . I should know 'cos I did hang gliding a few years back in a place we call Cornwall .I don't have a model ready for a (& I quote ) good blow job -but am thinking about the "Red Ned" plan in this months mag . It's not the prettiest of  models & needs a few more curves here & there, ie wing tips / fin BUT I have loads of wood I want to use up . It's a very big span for mostly good old balsa at 110 inches

Edited By Myron Beaumont on 12/04/2010 16:28:40

[Tim Mackey]

Indeeed....20 MPH is very mild stuff on the lovely smooth coastal site at the Great Orme - several of us hardly even bother if anything less that 25MPH is likely, and the fun starts when it starts hitting 60 MPH. If you have the right toys, even 80MPH is flyable, and our Andy E has a great picture somewhere of him flying with the anemometer showing 100MPH. Not 100MPH on this particular day, but here's his son trying to fly off the edge.

 

Edited By Timbo - Administrator on 12/04/2010 18:18:11

[Tom Satinet]

in fairness it's not that windy further inland, but even so it's over 10mph quite a lot of the time. 

 

25mph up the orme as a minimum! no wonder you guys think wildthings are a good! 

[Ed Anderson]

The impression is that the glider pilots on this forum are mostly slope pilots rather than flat land termal pilots.

[Tom Satinet]

Ed,

I don't know of a UK forum that has a decent number of posts where this isn't the case. There is a forum called flyquiet, but the activity is pretty low.  

 

slopers love posting on forums it seems.........

 

 

 

Tom

[Erfolg]

With respect to forums specifically for the gliding fraternity, Barcs have their own forum. I have no idea how many members they have today or in the past, but suspect it is lower than lets say 15 years ago.

 

Addressing the issue of wind speed and the flying of electric/gliders. I believe that in distant past flat field glider modellers, often flew in wind speeds which although not as high as is typical for slope modellers, yet could often be in the 30mph range. Heavily ballasted yes. Requiring skill both to quickly use thermals and the judgement of how far down wind you could go.Models as strong as "brick buily  out houses"

 

In my opinion flat field fliers have in the recent past packed up their electric jobbies when the wind got up.Why, as a consequence of most earlier electric models being low on power (brushed motors), highish on weight (Nicads). Many of the models were essentially paper bags, useless in anything but a calm weather situation.  But things have been slowly changing recently, I sense that the rule changes could change electric gliders decisively for the better, or at least see us flying in a broader range of wind conditions.

 

With the higher powered drive trains and the 200m limit I strongly suspect models will again return to the concept of dealing with both light air and strong winds. All those models consigned to the junk heap, The USA Sagittas, Shaun Bannister Algebras will again by viable for fun flying. I suspect that many flat field models at the cutting edge of competitive capability will owe  more than a little to the super slick, strong mouldies used on the slope, with electric power, in the  +100" SPAN.

 

Yes, I once again long to hear the scream or howl of open class model, descending from a thermal flight, heading for the landing circle as the slot ends. No more rustle of film as yet another lightweight clone of a bubbledancer flutters down in  the zephyr like conditions. I sense that revolution  is to occur not evolution, the 200m concept could be moving electric gliders forward to 15 or so years ago Ehhhh????

 

Perhaps in another 2 years we will not all climb back into our cars if the wind is above 10mph.

 

Erfolg

[Former Member]

[This posting has been removed]

[John Muir]

My first thought was 'full house', obviously. When did you last see a full size glider without ailerons? But the full size has the advantage of a pilot with a turn and slip indicator and is turned using both rudder and ailerons. Roll into the turn with ailerons and kick in rudder to counter the adverse yaw. If you only use one or the other, then either way, you'll get a skidding or slipping turn which is very inefficient, and you'll lose height. Now how many model glider pilots use co-ordinated rudder and aileron to make a turn? And even if they do, how do they know they've got the balance right? So I reckon, from an aerodynamic point of view, it probably makes very little difference. Models probably don't make very efficient turns either way.

For a polyhedralled floater, rudder will do nicely as it will roll itself into a turn adequately.

For a high speed slick model, ailerons will be best because on rudder only the thing will probably skid sideways for a while before rolling into the turn. Better to 'bank and yank'.

I only fly a rudder/elevator electric glider with lots of tip dihedral and you can see that if you apply gentle control inputs it turns quite flat. If there was a pilot on board he'd be grabbing for the stick and trying to roll it into the turn to put the ball in the centre. But for my model it works fine.

 

[Erfolg]

John

 

I suspect we have not tied down, what we are all trying to do.

 

My own thoughts are related to primarily open electric type modelling, using the 200m cut out. Or even the multitasking type winched models. In other words competition.

 

In this case full house is required, for such things as.

 

a) Crow braking for precision landing.

b) multi setting elevator

               i) For penetration mode.

               ii) For loitering

               iii) For the climb out

c) Multi setting trailing edge

               i) as b)

d) Aileron for more effective turning

 

It is apparent that a suitable computer radio is required to realise all these requirements.

 

There will be situations where rudder/elevator are all that is required.

 

I also agree that in the past the rudder/elevator/airbrake model was the result, of servo size, servo weight, cost of servos and the lack of computer radios, this was 20 years back.

 

Edited By Erfolg on 20/04/2010 18:29:29

[John Muir]

Erfolg

 

You're probably right. The OP was about thermal duration soaring but there are, apparently, numerous different versions of this. Electric powered or winched. Floater or 'penetrator'. And so on.

I think the crux of the original question was do ailerons make for a more efficient glider?

My point was really that we can't tell. Using only rudder or only aileron (leaving elevator input aside) can't be very efficient either way. Rudder only yaws the plane into a boat turn, then the inside wing drops into a bank. Very draggy. Aileron only rolls the plane, then it slips into a turn. Also draggy. With ailerons on a high aspect ratio wing, you also get rather a lot of adverse yaw, which points the nose out of the turn, even more drag. So yes, you can get more efficient turns using ailerons, but only if they're used with the correct amount of coordinated rudder. And that's very difficult to estimate if you're standing on the ground with no instruments.

Very interesting question actually. It is relevant to all models to some extent. Most of my power flying pals, if asked this question, would probably say 'what's a rudder?'.

[Ed Anderson]

I am thrilled that this has been such a lively discussion.  I have certainly enjoyed it.

 

As to the original poster, let me restate the topic of the thread.  I wanted to know the preference of the pilots on this thread when it comes to RES vs. full house gliders for themal soaring. 

 

I have both and fly both in competition.   I sometimes choose my RES glider to fly against the full house birds when the lift and the wind is light. 

 

While I am a competition pilot, this topic is not specifically about competition flying, but I did have thermal soaring in mind.   Seems most of the pilots responding are slope pilots so that skews the answers.

 

 

As I see it:

 

R/E/A/F - For thermal soaring, full house gliders give you more control, but that comes at the expense of more complexity in the radio and more workload on the pilot to take advantage of the controls.  They typically weigh more than the RES gliders, though not always.  And they usually require more attention from the pilot to keep the plane flying properly. 

 

Typical full house gliders have less wing dihedral so they are less self correcting.  Take your eye off the plane for too long and you might be in trouble.  This can become challening when flying at great distances.  And new, inexperiened pilots are more likely to make mistakes with the many control and trim options that are typically flown with a full house glider.

 

 

RES - Rudder/elevator/spoiler gliders are typically lighter, thought not always. By design they are more self correcting and provide adequate control in all but the most windy conditions.  Add some ballast and they can do pretty well in moderate wind.  You decide what that means.  

 

With the addition of spoilers you can achieve a high level of precision in landings.   RES gliders are easier to fly  at great distances, in my opinion, because you don't have to manage them minute by minute. As the controls are simpler, new pilots are less likely to make mistakes.  Release the sticks and look away for a time and they will typically fly on their own.  Get into a thermal, add a few clicks of rudder trim and you can put the RES glider into the thermal with little management.

 

In the US, both are popular.  What I have learned from this thread is that R/E and RES gliders are not common in the UK and perhaps not generally popular in Europe.

 

The main reason seems to be wind.  Where it seems calmer wind days are more common in the US, it seems that the UK has much windier conditions most of the time.  So full house gliders are the norm and RES is the exception.

Edited By Ed Anderson on 20/04/2010 19:23:52

Edited By Ed Anderson on 20/04/2010 19:29:46

[Erfolg]

Quite agree with your general conjectures.

 

I tend to define efficiency in this instance, from the perspective of the ability to win. In that aspect at present it is the full house.

 

What has really surprised me as a recent returning modeller, is the efficiency of the moulded wing.

 

I believe that in the distant past, I did know a very small number of modellers who could build a built up wing with an accuracy almost as good as a moulded wing, from an NC produced mould. Nearly, but not as accurate.

 

I have also seen many built up  wings as strong as a moulded wing. But at the cost of a lot of weight and construction time.

 

I have even seen built up wings with ailerons which incorporated seals to maintain profile. But nothing compares to the silicon or moulded cloth hinge  of the moulded wing

 

 

Looking at the moulded wing, it is more accurate, lighter, stronger. Probably an average moulded wing, beats hands down the best of my built up wings, I hasten to add built by others.  So even here my old rudder elevator wings are no where near as efficient, as the moulded aileron wing.

 

It is all interesting though and a good debate

[John Muir]

Ed, you certainly know how to ask an interesting question.

 

I don't even fly gliders all that much, but you got me thinking. I certainly can't comment on pilot preference as I've never flown a full house glider.

 

As for the UK being windy, well that's why we're so into slope soaring.

[Erfolg]

Ed

 

Only last week I was examining and speaking with one of the UK manufactures of moulded thermal gliders/electric.

 

I noticed that the model that was being flown, had dihedral, which surprised me. Mainly because there happened to be a very expensive F3b model doing its thing, at the field. Although similar there were conceptual differences.

 

I know you know that thermal models hopefully spend as much time at high altitude as can be achieved (in principal). I think this full house mouldy has all the characteristics, of my old thermal models, but better.

 

There is a price though, it is called money.

 

I still measure performance compared to my old very much deceased (and much loved)  Sagitta 900,  the mouldy is far better. I say this with heavy heart, as I still have a lot of

100s and open wings and a few bodies.

 

I do wonder what has happened to all the "Clean Machines", "Algebras", "Birds of Time" and of course "Sagittas". Have they all been killed, smashed beyond repair. I have elecrtrified my old EMP Algebra, fibreglass body, glassed  3m wing. It just takes to much effort to put it all togeteher. It wll still out perform most 2m ARTF easily.

 

There are however an incredible number of the cheap Far Eastern, rudder elevator models from, although it must be remembered these are sports machines, totally outclassed for competition. There most attractive aspect is there low cost.

 

Again I have been very careless that most gliders at our club are electric powered, except when it is a F3b.  

[Ed Anderson]

I guess I need to start a discusion about slope soaring.