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zerts
07-27-2006, 12:13 AM
Not yet into model sailplanes - did any of you lose plane in monster thermal? Are there hi-priced models with speed brakes or spoilers? Do you just put the nose down and fly straight out of the thermal or cross-control to slip down?

Slow Go
07-27-2006, 05:50 AM
Didn't loose it, however I was close. A friend and I where at the field to practise for a while. I came off the hi start and right into a nice thermal. After about 30 minutes, the thermal I was in decided to get serious. It took me into a building cloud bank. That turned into the most exciting and scarry flying I've ever had. I dived, hit the spoilers, counter turned and was also upside down. It kept wanting to suck my plane into the clouds. As luck would have it it finally let me out. For sure, I thought it was a gone. What a memory.

Sky Sharkster
07-27-2006, 12:21 PM
Hi Zerts, there's there's a couple of ways to get out of thermals with rudder/elevator models, one is to "spin" the model, that is, full rudder and "up" elevator, that stalls the wing and the model spins down, but you must be carefull when you recover as the model does build up speed, if you snap out of the spin too fast you can fold a wing. Another way is to click in a couple of degrees of "down" trim, not enough to make the model dive sharply, but enough to increase airspeed so you can move upwind and "punch" your way out, then keep heading upwind, away from the lift.
Most of the high-end models have spoilers, which help a lot. Some combine these with ailerons (dual servos) called "Spoilerons", that is they can either move in opposition-one up, the other down- or parallel, both up. This destroys so much wing lift the model descends flat, but you also need to mix in elevator trim to compensate for the airfoil change. The spoilers are also used to control altitude for spot landings. This requires at least 5 channels and a couple of mix functions on the TX.
A "Full House" setup would be separate flaps, ailerons, rudder, elevator. With this system, it is possible to program "Crow" function, that's raised ailerons (they still have aileron function but both are raised slightly to prevent tip-stall) lowered flaps, lowered elevator trim, all at the same time. This slows (nearly stops, actually) forward speed and the model "parachutes" down in a flat attitude. Like a bird landing.
Check out some of the glider sites posted on "Sailplanes" sticky like Esprit, Art Hobby, Shreddaire, Niagara Frontier (NF), NESail, ICARE, etc. You'll find a large range of performance, price and options.
Ron

Warden
07-27-2006, 12:38 PM
I have two sailplanes, one is a Great Planes Spectra with a polyhedral wing (a floater) and the other is a Kyosho Soarus with a straight wing and very little dihedral (very fast). Neither plane is equipped with spoilers. I only mention the different types of planes because I use the same method of escape from boomers for both types of aircraft.

There are two issues to deal with here, one is that if you don't lose altitude, your plane is going to become a semi-permanent resident with the angels. The second issue is that if you drop the nose in an attempt to get lower and you build up a lot of airspeed, you're going to rip the wings off the plane, either during the dive or when you try to pull out.

Both my planes come down FAST and GENTLY by putting them into a spin. I actually picked up on this by reading the directions that came in my Spectra kit, which, by the way, was fifteen years ago and I'm still flying the same plane! Just give the plane full up elevator and full left rudder. The plane will go into a spiral dive and WILL NOT pick up an excessive amount of airspeed. I suggest that you try the technique before you need it to see how it works.

Warden
07-27-2006, 12:53 PM
Sharster types faster than me!

Jason T
07-27-2006, 05:21 PM
Depending on the model I will typically start applying CROW (flaps down, ailerons up) or spoilers. However, on one occasion flying my old Omega 1.8 (full span ailerons), I had about 30 degrees up on the ailerons for spoilers and I was still going up. That was scary. However, I was lucky enough to get out of it and bring the model safetly back. I was really worried about overspeeding the Omega and ripping the wing off since it is such a light airframe.

zerts
07-28-2006, 08:39 PM
Thanks all for great advice. I used to pilot sailplanes years ago, was not unusual to get a 1000 foot per minute free ride, and the FAA required us to not exceed 12,000' ASL if we didn't have oxygen (don't really remember whether it was 10k or 12k feet). It was a simple thing to just put the nose down a bit and fly straight out.

AEAJR
07-29-2006, 10:39 AM
Model sailplanes are the best! I have a dozen and spend most of my flying time on them. I have 2 new ones that I will be preparing for competition.

I was in a booming thermal once that might have taken my Spirit away if one of the club members had not pointed out to me how fast it was climbing. I was new to sailpalnes at the time. The wall of the thermal was so strong that I could not just fly out of it. The plane would hit the edge and turn. I didn't know what to do and had maybe another 30 seconds before I would lose sight of it.

I handed him the radio and he put the stick in the lower left corner and basically stalled out of the thermal.

My two 2M planes have spoilers, which are a great help in getting down. My 3M planes are full house so I would use flaps or crow to pull them out of such a thermal as described above. However the larger planes penetrate better so generally I can just fly out of even the strongest thermal.

TLyttle
08-01-2006, 05:18 AM
Too many ways to dump out of a boomer, all mentioned above. I usually drive upwind to either the limit of my vision or go inverted; either one works. I have tried spinning out, but I have also had a spinning model keep going UP! Diffrent strokes...

TeslaWinger
08-26-2006, 10:10 PM
Agreed, TL! The Turn and Burn method works well but the lift may exceed the sink rate it produces! If you wanna fly in the big ones, spoilers- or camber control- are needed!

I believe you have experienced what hang glider and sailplane pilots call Cloudsuck!

The Latent Heat of Condensation is at work here as the warm rising water vapor loses its heat to the surrounding air which grows colder with altitude until it condenses into fine visible water droplets. This tremendous exchange of energy from the water vapor's change of state (altho a thermometer shows no change of temperature) acellerates the air upward to make a towering Cu- or a CumuloNimbus with the power of a modest A-Bomb!

Champion sailplane and hang glider world record pilot (and my long-time soaring hero), the late George Worthington yrs ago related such an incident. He was in a vertical dive, spoilers full out and still being pulled up under an ugly Cu-Nim, but such are the risks of soaring competitions!

Being under it, he couldn't tell it was rapidly becoming a mature thunderkiller! He was pulled into it and flying blind, he was beaten up badly, nearly stressing the airframe to failure until he saw a patch of light and steered for it, escaping the monster!


The point? Some days you eat the bear.. other days...

TLyttle
08-27-2006, 02:35 AM
The big thing is to get the hell out of it!!! Which is why I like to just drive upwind; eventually, you will find the edge of it and come down. The other side of the coin (there is always another side!) is that once you are out of the lift, man, you are OUT of the lift! Next stop...

I drive upwind until eyesight begins to fail, then I turn 90deg, and follow that visual limit until I am able to come home.

I have 20-15 vision with my windows on, so that is a major advantage (ask anyone whose plane I have found and rescued).

One thing you know is that if you have enough battery power, up you go again in the same thermal.

tillmas
09-15-2006, 03:29 PM
All of the methods listed in here are very good. One thing to remember is that you cannot spoil or crow or use any other lift based method to get out of a rising column that is rising with enough force to overcome your wing loading. This is especially true for the big boomers in the central plains, and is often compounded by people flying their RE gentle ladies with 5 oz/sqft loading on those days.

The only way to get out of a pocket that is capable of lifting your entire mass (sort of like a powered model with a T/W >1) is to fly out upwind as TLyttle has said. The key to this of course is penetration, and therein lies the rub: sailplanes with light wing loading can't penetrate.

The moral: if you are going to fly on a big lift day, then don't bring the light sailplane, and never bring anything with a flat bottom airfoil.

Of course, if you fly a sailplane that had its wing sized for a 100 lb winch launch, you don't have to worry about zooming out of the bottom. That way you get most of your energy back in speed.

Matt

AEAJR
09-15-2006, 05:21 PM
Some real interesting posts here. The one about that full scale sailplane diving down a thermal and STILL gaining altitude is really scary.

And all I wanted to do was float around till I decided to come down.

TLyttle
09-20-2006, 05:16 AM
Well, that has to do with what kind of day it is. If the whole world is going up, expect a fight. If there is nothing but little bubbles that cap off at 600', expect a different kind of fight!

As far as flatbottoom airfoils are concerned, they can be made to move if you want. On windy days, I would shim up the TE of my Oly11 and get all the "penetration" I required. Mind you, I had sheeted the LE of the wing full-span, and it would dive vertically without flutter, yet bounce around in the lightest bubble. A lot of guys ballast up for wind rather than mess with the decalage, but if you DO find light lift the ballast won't allow you to follow it.

And if you feel that you must ballast up, usse the biggest RX battery you can find, then you have all day to get it back down...

AEAJR
09-20-2006, 02:04 PM
All of the methods listed in here are very good. One thing to remember is that you cannot spoil or crow or use any other lift based method to get out of a rising column that is rising with enough force to overcome your wing loading. This is especially true for the big boomers in the central plains, and is often compounded by people flying their RE gentle ladies with 5 oz/sqft loading on those days.

Matt

I have never been in a thermal this strong, thank goodness. :eek:

The other approach I have seen people use is to go inverted and dive for the wall of the thermal. Between the reduced lift of the wing and the dive, they have gotten out of strong thermals with Aspires and GLs.

But I guess if the lift is strong enough, you may as well kiss it goodbye.

TeslaWinger
10-04-2006, 12:57 AM
And all I wanted to do was float around till I decided to come down.

:D Ain't THAT the truth!

It used to be hard to get the plane way up there- which led to discoveries in electricity and power. Now GETTING DOWN is the challenge (sometimes) which is more about technique and drag control surfaces as well as choosing the right plane for the conditions!

"Birds fly- men drink!" - The Man Will Never Fly Society

TW

deauxrite
10-10-2006, 02:46 AM
I got out the hard way. Full up elevator and right rudder got the spin going and the glider headed back toware earth. Unfortunately, when I started the recovery the left wing folded. I heard it snap and down she came. Lucky for me she landed in a field with tall grass.

I flew that airplne the next weekend.

TLyttle
10-11-2006, 02:46 AM
Yup, that's the hard way alright... The name of the game there is to SLOWLY release the rudder, throwing it into a stall, and recover. Anytime you throw severe control changes into an already unstable aircraft, expect catastrophe. This is why I advocate just driving straight upwind until you are out of it.

However, I'm glad that you were able to repair your model.

Up&Away
11-09-2006, 02:30 PM
A few weeks ago I was slermalling my 42" Unicorn. There was very little wind, as we were in between periods of rain. Dark clouds were gathering over the sea, and while flying under them my 'Corn was literally sucked into the clouds. At first, when I saw my 'Corn rising as if she was in an elevator I was amazed and excited. I kept circling under the cloud, about 1000 away from the slope and going up. Straining my eyes to keep eye contact, suddenly she was gone! Almost as if someone flicked the cloacking device switch from Startrek! It took all of half a second to realise my 'Corn was in the clouds. It then took another 10 seconds to decide what to do (full throttle? nose down? nose up? tight circles?). Knowing that the 42" version tipstalls nicely, I pulled gently up. Within a few seconds I saw her spinning out of the clouds. I stopped the spin, and dived back to shore. Time for some underwear change...

TeslaWinger
11-12-2006, 12:09 AM
A few weeks ago I was slermalling my 42" Unicorn. There was very little wind, as we were in between periods of rain. Dark clouds were gathering over the sea, and while flying under them my 'Corn was literally sucked into the clouds. At first, when I saw my 'Corn rising as if she was in an elevator I was amazed and excited. I kept circling under the cloud, about 1000 away from the slope and going up. Straining my eyes to keep eye contact, suddenly she was gone! Almost as if someone flicked the cloacking device switch from Startrek!

That Cloaking Device sure makes 'em hard to see! Since you were between rain showers the lift was minimal (enough)- or you woulda never seen that one again! Congrats! I love it when they return home!

TW

Up&Away
11-12-2006, 07:37 AM
And in continuation, last Friday I was (again) flying my 'Corn. The wind wasn't good for sloping, so I went to a club field. Thermals were popping up everywhere, and I got caught in a real strong one while already far away. It took a while (and a flying buddy standing next to me) to realise this was going out of hand. Even while diving I went up! The only way I could punch out of the bubble, was opening full throttle and pointing into the wind. I had a heck of a time getting her back because of the incredible turbulence and wind gusts in the area..
I'l have to bring more underwear when I go flying...:o

bobthenuke
11-28-2006, 06:04 PM
A friend and I were flying his Oly one day and it got caught in an "Arizona Trash Hauler" and that was the end of it...forget spoilers, spins,dives, etc. It quickly spec'd out and was never seen again.

I've been in thermals while flying full scale sailplanes that took some pretty good speed runs to get out of and the same while hang gliding. There's nothing like *trying* to get down and notice you're still going up that'll make your butt pucker to the point you couldn't drive a pin in with a 10 pound sledge. ;)

bob

Ribcracker
11-29-2006, 01:55 AM
Okay, so here's another story. About a year ago I was flying my SlowStick in the field next door when it caught a thermal and rapidly began to rise. I thought "Great, free ride" so I cut the throttle and watched as it climbed even higher. My neck was sore from looking straight up so I laid down in the grass on my back and flew lazy glider-type circles. Pretty soon I could no longer determine the orientation of the tiny speck. I leapt to my feet and pushed the stick forward to nose it over. Nothing...maybe it was out of radio range. And then I lost sight of it. I scanned the sky for what seemed like half an hour. Nothing...the reality that I had lost the plane began to sink in. I got into the car and drove downwind searching the sky and the fields on both sides of the road. Nothing...so I made up flyers, put them in mail boxes, and affixed signs to stop sign posts.
This plane carried about $250 worth of equipment on board so that was one aspect of my grief but moreover, I had become very fond of this plane as we had spent a lot of time together (upwards of 200 flights, surely). I felt a deep sense of loss and sorrow. That night I had fitful sleep with frustrating dreams of fighting the controls to get my plane back. By morning I was starting to let go and accept the loss.
When I got home from work on Monday there was a message on my answering machine. A man had found my plane. It was in the top of a tree in his yard...a mile and a half from here! As fate would have it, the section of the tail with my name and phone number on it had torn away from the plane and landed in his yard. He had not seen my " wanted" posters because I didn't disperse them that far.
Anyway...an extention ladder and some dicy tree climbing had my plane back. The damage was pretty extensive but I was able to salvage most of the electronics. By the next morning the plane was almost completely rebuilt. When I flew it a day later I was watching it very closely.
Peace,
Bud

TeslaWinger
11-30-2006, 04:00 AM
Now you know why hang glider and sailplane pilots wear a parachute! It's not in case the plane just falls apart- its in case it is torn to pieces, shorn of its wings and spit out with only seconds left to get out (or fire a rocket, ballistic or hand deployed chute in a broken HG) before the speed gets too high in that sleek plummeting coffin. If you are high enough to be on O2, better make sure it stays on thru the process of an emergency exit to a very cold freefall!

The lift continues up thru the Cumulus and CumuloNimbus clouds and can be soared on instruments- but even the very best of pilots have been lost dealing with such powerful forces inside the clouds after getting too close and the Cloudsuck gets 'em!

I recall a report of a HG pilot who soared the windward face of a Cumulus cloud as if it were a ridge! Lots of fun till you find yourself IN IT! Interesting concept tho...

RC sailplanes might someday fly wave lift to 60,000 ft with the big boys with deep freeze batteries and onboard video and telemetry- and no frozen toes! 50 below at altitude is a reminder that the sun does not heat the air- it heats the ground and convection distributes it upwards, hence all the commotion! Wave lift is an extension of ridge soaring- a stratospheric one!

When I lost my Ascent overhead OOS ne'er to return I knew I needed a bigger glider- and SPOILERS! If I had a videocam and AV/TX aboard it would not have been lost, just forced reliance on the video link to keep it local and descend at a safe rate after escaping the Megalift.

Nice to have a backup in case of Skysuck and its acompanying OOS Syndrome for us Hard Of Seeing People! Being able to control the airspeed and keep the wings level by RPV will go a long way to the model's survival if it gets lifted up beyond visual range involuntarily- or otherwise! :D

So I specked out my 3 meter VBOT last weekend- now what- a 4 meter- or sit back in the lawn chair and fly it by the HMD?

Good luck- and remember: "Never bring a knife to a gunfight!"

TW

Up&Away
11-30-2006, 07:37 AM
...- now what-...

I think you're ready for one of these: http://www.icare-rc.com/lf20.htm:)

bobthenuke
11-30-2006, 12:14 PM
I *have* soared the windward face of a storm front in my HP-18. Everything was fine until I found myself in the bottom reaches of the cloud, and then suddenly into a grey out condition. I took a strike and lost my electronic instruments (radio and vario) and ony had altimeter, compass, and backup vario to tell me anything, which they didn't. After dumping the landing gear and pulling about 20% flaps I dropped out at an inverted position aproaching Vne (180) quickly. I was able to pull out but I already had one hand on the last canopy pin to get out in case I broke apart. Fortunately I was able to get down in one piece but it was the ride of my life. Yes, there's a reason for a chute as well as toe straps on the rudder pedals. This is a true story.

bob

TeslaWinger
12-06-2006, 01:31 AM
Up & Away, I think you're on to something! I could see it 2.25 times higher than a mere 3 meter=- even more if I dig a trench in my crowsfeet and squint mightily! Forget folding props- make the whole thing tuck neatly inside- just don't forget to stop the prop! THUMP!

It's slicker than snail goo!

The only problem is that it is so clean that hanging a videocam on it would be a crime of horrendous proportions- at least aerodynamically. OK, so it only glides 40 to 1 instead of 50... :D

TW

arnheimacres
01-02-2007, 05:25 AM
This story doesn't relate to gliders, but does fit the topic. Many years ago when I was in the 82nd Abn Div at Ft Bragg, NC, I was participating in what we called a "Hollywood" parachute jump. This meant that we were jumping out of helicopters without the normal equipment - just the main and reserve chute. Catching thermals while parachuting is obviously great because it lengthens your "ride." You always know you catch a thermal because everyone else around you will suddenly start falling (actually you are rising). On this particular day I had completed a jump and was racing back in to get another parachute so I could go again, when I noticed people watching something. One of the jumpers on my jump had remained quite high after everyone had landed. He then began going up. I'm not sure how high he actually went but it was well beyond the initial drop point. Then something really wierd happened. He began going horizontally. One of the helicopters left to follow him. The trooper went, I believe it was about 15 miles to the neighboring town of Fayetteville and landed in the parking lot of a shopping mall. I remember the cover of the local paper the next day showed him carrying his parachute to the waiting helicopter in the parking lot to retreive him. I remember the trooper's comments were that he loved the ride, but was a bit nervous about all the power lines he was crossing as he finally decended.

AEAJR
01-02-2007, 12:47 PM
Wow! That is a great story.

I guess he could have used his guide wires, or whatever they are called to turn back toward the landing zone, but would have have had enough authority to get out of the thermal? I guess if the lift were strong enough he could be pulled into a cloud. I hear clouds can be quite violent inside.

arnheimacres
01-02-2007, 10:44 PM
It was an interesting day AEAJR. The parachute we were jumping at the time (MC1-1), which isn't used any more, had a forward speed of 8 knots. I'm sure he was trying as hard as possible to get back, but it wasn't happening that day.

TeslaWinger
01-03-2007, 12:57 AM
I *have* soared the windward face of a storm front in my HP-18. Everything was fine until I found myself in the bottom reaches of the cloud, and then suddenly into a grey out condition. I took a strike and lost my electronic instruments (radio and vario) and ony had altimeter, compass, and backup vario to tell me anything, which they didn't. After dumping the landing gear and pulling about 20% flaps I dropped out at an inverted position aproaching Vne (180) quickly. I was able to pull out but I already had one hand on the last canopy pin to get out in case I broke apart. Fortunately I was able to get down in one piece but it was the ride of my life. Yes, there's a reason for a chute as well as toe straps on the rudder pedals. This is a true story.

bob

Bob, that is the ultimate slope- an aproaching cold front. I've read accounts like your experience. It's like whitewater rafting in the sky without the rocks! Glad you didn't have to pull that last pin!

I remember a story of a military pilot who had to punch out in a thunderstorm and was beat up badly by the updrafts, downdrafts and hail as his chute kept him up for a long time inside the CuNim. Theres nothing like 100mph updrafts right next to 100mph downdrafts to tenderize ya!

... and most people don't even know it's happening right over their heads...

AEAJR
01-03-2007, 01:34 AM
Theres nothing like 100mph updrafts right next to 100mph downdrafts to tenderize ya!

... and most people don't even know it's happening right over their heads...

I have heard stories of gliders being pulled up into the clouds, then minutes later, pieces falling out of the sky. They may be fluffy on the outside but they seem to be churning on the inside.

TLyttle
01-03-2007, 02:47 AM
Ooooh, yeah, airborne meatgrinders, and guess who the meat is?

In the Old Days, a reserve chute was just a canopy to save your butt when the steerable chute went Wrong. And the steerable chutes Went Wrong about every 8th jump.

My buddy did a jump&dump at 12,500, steerable went duff, so therehe was, hanging on his non-steerable at 12 grand... took him an hour and a quarter to land, many miles from jump zone. It took him nearly that long to hitch back to the zone...

TeslaWinger
01-03-2007, 03:02 AM
zerts;91215]Not yet into model sailplanes - did any of you lose plane in monster thermal? Are there hi-priced models with speed brakes or spoilers?

If I hadn't lost my Aspire- oops- my Ascent... E sailplane straight overhead totally taken by the sky, then I wouldn't have converted my Aspire high-start 2 meter glider to electric and gotten that magic soaring flight I posted a coupla weeks back. Who knows? Balsa Karma! :D It's all good... 'cept it's Winter!!!

There are shape shifting camber changing flaperon wings if you like a complex and capable sailplane- or just the built in polyhedral stability for R/E/T simplicity.

This just might be the Winter I add the spoilers to my Bird Of Time electric convert. Just like that Bunny, she keeps going and going without brakes to shorten the landing! Even had to spin her down to where I could still see that 10ft BOT wing while soaring! It gets risky playing up high on a cookin day... besides, its not dignified to screw your way down like that! :rolleyes:

Forget the Forward Trim and Plow Along At High Speed Plan! It's quite a sight to see a wing- or wing halves tumble endlessly down from 800 ft along with an expensive arrow leading the way to Earth! Don't fly fast in rough air- it tends to RIP THE WINGS OFF!

Better to spiral down tightly after getting out of the strongest lift area, controlling the speed and descent with "down rudder" in the steeply banked turn. Less rudder and it becomes a near level circle; more, and it comes down fast- but be careful... some days you could throw rocks into the sky- and they won't come down!!! So get comfy- this could take a while... :cool:

Flaps or spoilers let you dive steeply and 'should' keep you from exceeding wingslapping speed even vertical! Big difference!

Do you just put the nose down and fly straight out of the thermal or cross-control to slip down?

Just once... :D

AEAJR
04-30-2008, 07:24 PM
One escape method that I was told to use on a R/E or RES gliders is to put the stick in the corner. This gives you fulll elevator and full rudder. This induses a spiral dive via induced stall. In all but the most extreme situaitons this will drop you down throught the thermal and may take you out of the thermal.

mred
05-01-2008, 02:35 AM
I bought a ready to fly sailplane from a guy and while I don't know what it was, I think it was an Olly converted to E-Power with one of those great Hyperon (I think I spelled that right) motors in it. You know, one of those that tapers in the front to make it fit in better. Anyway, I had flown it a few times and was having a ball with it until one day I caught this nice thermal. I trimmed in some rudder to keep it in a nice slow turn and it was going up nicely and I was having a ball. This was the first time I had caught a real nice thermal. Well I decided it was time to bring it down a little lower and I while it was not specking out at the time, I just wanted to bring it down lower and see if I could go again. I was a little shaky about letting it speck out as I did not have anyone with me and really did not want to loose that plane. Well I put some rudder in and nothing. I put more rudder and nothing. I hit full rudder and full up and nothing. I hit the motor and nothing. No response from anything. I tried everything and got nothing. All I could do was stand there and watch my bird get smaller and smaller. Finally it went OOS and that was the last I ever saw of it. I did follow it in the care for awhile, but after I lost it, I never saw it again and it looked like it was going to climb forever.
I had my name and everything in it, but there is also a good chance no one ever saw it after it came down as there are a lot of woods around here. For all I know it could be sitting up in the top of some tree just waiting for me to find it. I know the battery was good because it was the first climb on a fresh battery and it was big enough to last a long time. Something happened, but I have no idea what it was as I never recovered the plane. That was about 8 months ago and if I haven't heard anything by now, I guess I never will. Next time I am going to put a PCM receiver in there and put a fail safe for a spin. Maybe at least then I'll be able to get something back. Has anyone found a yellow and day-glow pink sailplane laying around in the back yard lately??? Oh well, better luck next time.

Ed

AEAJR
05-01-2008, 05:40 PM
Ed,

It sounds like you lost radio contact with the plane. While I have been in some pretty strong thermals, I have never had the plane be unresponsive.

I have seen planes lost in thermals, but it has never been a case of loss of contact or response. It has been an inability to break out of the lift. In some cases it was that the lift area was so large and so strong that they could not find the edge. No matter where they went they were in lift and rising. They were flying with the nose down and the plane continued to rise.

I have been in thermals that spanned the entier field. At high altitude, where the tail was just barely visable on a 3.4M plane, where I was flying, the lift zone was at least 1/2 mile across.

No matter where I went I was in lift. We had 7-8 planes up in this lift in all corners of the field. And when that thermal died, the entire sky turned to sink and every plane in the sky started to come down. It was a very dramtic event when the lift died. Everyone announced the loss of sink within 30 seconds.

That was a 58 minute flight. I had to fly down several times during the flight as the plane would just continue to climb if I let it.

The composite planes, or the wood planes with carbon reinforced wings have the advantage here because we can more agressively dive while in a such a lift situation.

The light weight poly wing planes can't take as much speed. That is why the controlled spin is often used, It kills the lift of the wings but limits the top speed the plane will reach in the dive. For R/E or RES planes this seems to be the best escape approach when you are in one of these lift monsters.

mred
05-01-2008, 11:53 PM
Well, seeing as how I never found the plane, the only thing I could think of was the receiver went dead. I know the battery was good and the transmitter still works good, so I figure the receiver went. I had a Berg 7 channel in the glider, so I know it was not out of range, but for the life of me, I cannot think of anything else. If a servo went, I would still have had some kind of control and I could not get the motor started again, so that leaves the receiver. I have no idea why it went out, but I think it did. It may have come unplugged for all I know. I had the trim set for a nice slow turn and it looked like I was in the center of the thermal as there were a couple of birds in there with me flying around my glider for awhile, but they took off cross country and mine just stayed there. I was kind of a hazy day and that may have had something to do with it going OOS on me, but I can't say for sure on that either as I am still in a steep learning curve on this glider thing.

I have since had my 2 meter higher then that one was and it has a Berg 7 channel in it and I have never lost control of it, so I can only guess as to why it stopped responding. I am flying a Vista now with a BL motor setup and it flies great. I am starting to learn how to find thermals better and how to trim it out, but I am much better at finding sink. Anyway, I am working on a Spirit 100 for my second glider and thinking of an Olly III down the road.

Haven't quite made up my mind yet, but I did have an Olly a long time ago and I really liked it. I had that one while I was stationed in Indiana and I loved flying that one, but I crashed it just before I retired and for some reason never got another glider until just a little while ago. I am finding out how much fun I used to have with my old Olly and while I am not going to give up my powered planes, I really like gliders a lot.

I fly them with motors because the field I have is not big enough to use a Hi-Start. I have go to the flying field and that is an hour away. My flying field for gliders is 4 blocks. Big difference in travel time. Well that's enough of my babble for now. It's all water under the bridge anyway. Take care everyone and have a nice day.
Ed

FlyWheel
05-02-2008, 01:09 AM
Since no one's said it, I will; make sure you have your name and address/phone# on your plane, just in case!

mred
05-02-2008, 01:25 AM
I always do, but like I said, there are a lot of woods around here, so it may be that no one has even found it yet. I just may have come down in the middle of the woods someplace. I always put my name and address on it and some times I even put my AMA number, but that does not mean you will always get it back. Wish it would come back as I would love to have that plane and motor back, but I figure it is gone forever now.
Ed

Desertdog
02-28-2013, 01:25 AM
Last year i had a super boomer and it was a 1/4 mile wide (just guessing) I had a e bot and it flew very well, Got into this boomer and was getting very small and decieded i had better come down , so i just gave it down elevator went up wind and no problem, Came back to me and did it again. I have a phoenix 2000 and a pulsar 3.2 e so i grabed my phoenix an launched and it went up like nothing i have ever seen (was mind bogling) i lost sight twice so i gave it flaps and tried to dive it but then decieded to hit the spoilers. Eventully i got it down but the morall of the story is a phoenix 2000 742 is not a soaring icon but it was awsome to watch it dissapear and i would not make a statement how high it went but when you canot see it how high is it

mred
02-28-2013, 02:04 AM
Last year i had a super boomer and it was a 1/4 mile wide (just guessing) I had a e bot and it flew very well, Got into this boomer and was getting very small and decieded i had better come down , so i just gave it down elevator went up wind and no problem, Came back to me and did it again. I have a phoenix 2000 and a pulsar 3.2 e so i grabed my phoenix an launched and it went up like nothing i have ever seen (was mind bogling) i lost sight twice so i gave it flaps and tried to dive it but then decieded to hit the spoilers. Eventully i got it down but the morall of the story is a phoenix 2000 742 is not a soaring icon but it was awsome to watch it dissapear and i would not make a statement how high it went but when you canot see it how high is it

Back in my old FF days. we would call that OOS and any time you hit that, it is bad news. It's great when you are having fun, but It pays to watch them pretty close. If you ever loose it in a big thermal and wait a few seconds before deciding to hit the spoilers. It just may come down at a different heading then what it was flying at when you lost it. It is possible to loose one of those things even if you do hit the spoilers. I lost one in the sun and will never do that again. I didn't have spoilers on it so I put it in a spin. Believe it or not, that thing had come out of the sun and gotten in back of me and I never saw it land. Good thing a friend of mine did, but wouldn't you know it, it landed in a tree about 40 feet off the ground. I did get it back shortly after that, but it was mostly because that stupid tree had very few leaves.

It doesn't make to much difference what altitude it is at if it is OOS, so just hang on and try and hit the spoilers before it does go OOS. Back in my FF days, we prayed that someone nice would find it and give us a call so we could go get it. Now days when we do FF, we do it with R/C guided so we don't have to chase them, but without spoilers they can still go OOS if you let it. Other wise, we put in in a tight spiral and bring it down. Some of them will even spin or almost. Rudder only is harder to bring down that way. Most of my old FF models are RE so I can fly it back down and not have to worry about loosing it.

How high were you when it went OOS? Just a little higher then you should have gone. Put an Eagle Tree Alt module in it and it will tell you how high it went next time. It's a stand alone item and after it gets back down on the ground you can just look and see how high you went. It only cost $38.00, so the cost is pretty good. I never send a glider up without one now. Great little unit.:ws:

Ed

kyleservicetech
02-28-2013, 02:26 AM
How high were you when it went OOS? Just a little higher then you should have gone. Put an Eagle Tree Alt module in it and it will tell you how high it went next time. It's a stand alone item and after it gets back down on the ground you can just look and see how high you went. It only cost $38.00, so the cost is pretty good. I never send a glider up without one now. Great little unit.:ws:

Ed

Back in the mid 1980's I was part of a team that did cross country racing with giant model sailplanes. The route was 45 miles on local highways. If you ran out of lift, that was the end of your flight. The guys from California were making the round trip in under 1 1/2 hours. These models had wingspans of 14 feet or more, and were capable of flying over 100 MPH.

One flight, we saw a full scale sailplane in our restricted area. One of the local club members recognized the full scale plane, we found out from the full scale pilot that our models were flying at 6100 feet, straight up.

That's called Specking out. Take you eye off the model, and you'll never see it again.