DG-808S - Model for the Care of the Ultimate Competition Glider
The DG-800S is preferred by competition pilots who want to get the best out of their glider, and the slimmer fuselage of course produces less drag than the fuselage of the motorized DG-808B.
Considering the still fairly low production numbers of the "S" it is amazing how many competitions have already been won by pilots with DG-800S.
For these competition pilots in particular we now offer a new feature which will give this type significant advantages over the other glider types available on the market. Let me explain the following:
Compared to the models ASH-26, Ventus 2 and LS-6 in the 18 m class, and ASW-27, Ventus and LS-6 in the 15 m class, the DG-800 has always had a relatively large wing area. In the 18 m version the wing area is 11.81 m² (in the 15 m version it's 10.68 m²) and is therefore approx. 1 m² higher than the wing areas of the competitors' gliders. As the maximum overall weight of all the compared glider types is very similar (between 500 and 525 kg), it becomes clear that the DG-800 is often flown with a lower wing loading than the other gliders.
Why is that?
Well, this depends on what the glider designer thinks. In Germany with its low thermal strengths a big wing area with low wing loading is an advantage - that's why the 800 has the reputation of going up "like a paper bag". For international competitions held in Southern countries where you encounter "stonking thermals" the maximum overall weight is however not sufficient to achieve the desired high wing loading.
So what is better?
This really depends on the various competition pilots' preferences, and they all have their own views on this.
Now this is where the major improvement of the DG-808S enters the stage. It's the upgrade to the optional equipment for the
DG-808S Competition
- a completely newly designed water ballast system plus an increased maximum overall weight to 600 kg in the 18 m class and 570 kg in the 15 m class.
This means in particular that the 800S in the competition version is equipped with 6 integral water tanks of 239 liters total, three of which are always to be emptied at the same time.
Both inner wing tanks are linked to the front fuselage tank and are emptied by means of a lever. These three tanks can hold a total of 150.5 liters of water.
The two outer wing tanks are linked to the second fuselage tank and can hold 88.5 liters of water.
This leads to 4 different possible loadings where the nose-heavy moment of the wing tank is always exactly compensated for by the tail-heavy moment of the fuselage tank, i.e. the glider always flies with the optimum C of G.
- no ballast
- 88.5 kg
- 150.5 kg
- 239 kg
Thus in the 15 m version it achieves a maximum wing loading of 53.4 kg/m² - a value that can now compete with the other glider types. In weak thermals however you can dump all the water from the DG-808S (and probably also put out a small forest fire at the same time...
) - and then you'll benefit from the unbeatably low wing loading of 32.4 kg/m² again.
Do our competitors do the same?
Well, apart from the fact that the LAK-17 can be flown with 545 kg overall weight, a weight increase doesn't make a lot of sense for the other manufacturers. The ASW-27 for instance "only" has a max. weight of 500 kg. But due to the low wing area of 9 m² its wing loading is 55.5 kg/m² - and more is not possible. So our competitors already have the high wing loading that is desired in good conditions - but they still have it in weak thermals when a field landing is looming...
The weight increase for the DG-808S became possible due to the very robust and well-sprung undercarriage which had enough reserves to allow this increase in weight.
With the DG-808S Competition we can now offer the ultimate competition glider which allows the adaptation of wing loadings to the weather conditions much better than any other competing model.
The DG-808S Classic however still comes with the familiar water ballast system:
120 liters in two water bags and a tank in the tail are standard - the bigger water bags with 174 liters can be ordered as an option.
As the current version of the DG-800 has shown that this glider is already at least at the same standard as all the other competing types - Ralf Fischer's first place in the German National Competition 2002 and Friedemann Küster's third place are just two examples - we reckon that with the "Competition" version of the DG-808S will make a further significant improvement a very real possibility.
From 2003 on all DG-800S will be built in the new version DG-808S - so you can order them as a "Competition" version straightaway.
In the following picture you can see the two handles of the water ballast system as well as that one for the NOAH system:
Safety
The DG-808S differs from the previous model in a few more aspects:
One of these is the reinforced safety cockpit which comes as standard.
Following the tests done by the TÜV Rheinland regarding the Crash safety of glider cockpits, we developed an optional reinforcement of the DG-808B's fuselage years ago. Unfortunately the old saying "Safety does not sell!" was again confirmed, and we've only received very few orders for this safety option.
The reinforced cockpit however had one minor disadvantage: The seat pan width in the cockpit had to be reduced by approx. 2 cm due to the additional stringers.
For the new DG-808S - both the "Classic" as well as the "Competition" versions - we have now used a slightly smaller version of the cockpit reinforcement, and this now comes as standard. In the new safety cockpit the seat width is no longer reduced - so the pilot won't even notice. However, in the case of a crash this new cockpit is designed to provide that bit of additional safety, which might avoid an injury or worse.
Of all competing glider types the "DG-808S Competition" offers the highest flexibility with regards to the wing loading.
This makes it a very interesting option for competition pilots.
Upgrade of existing DG-800S to DG-808S
A lot of people who own a DG-800S have asked us whether it can be upgraded to a DG-808S.
Well, this can't be answered in one sentence:
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The water ballast system of the Competition version with 4 integrated wing tanks and 2 fuselage tanks can't be retrofitted. This is easy to understand.
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The cockpit reinforcement can't be done retrospectively either.
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The changed flaperon sealing however can be done by any certified workshop - although the material needed is not cheap. There is also a technical note: No. 384-07.
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You probably won't need any improvement on the type of fabric. But there's nothing to stop you ordering new cushions.
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What is also possible and highly recommended, is the retrofit of the Piggott hook and with that also the parking brake.
This is detailed in the technical note No. 384-6. -
The bug wiper "garage" as well as the recesses for the optional solar panel in the fuselage can only be done on a new glider. So a retrofit is not possible.
To sum it up:
Piggott hook and parking brake are strongly recommended for retrofit
flaperon sealing and new cushions can be done
....and there is one more thing a lot of DG-800/808B owners want to know:
Can you get the higher loading
for the motorized version of the DG-808 as well?
Unfortunately the answer to this is no -"not in the moment!".
The increase in water ballast was only possible due to the very robust undercarriage of the "S" version. The motor glider is equipped with a different, slightly smaller undercarriage as due to the fuel tank there is not enough room for such a big undercarriage.
The smaller undercarriage is absolutely adequate for an overall weight of 525 kg - but unfortunately not for 600 kg.
Furthermore the DG-808C will not have integral water tanks, as water ballast is only an option and with bags we are variable and can install nothing or water or fuel bags or both.
But - we are working on this!
- friedel weber - 
Translation: Claudia Buengen
....and here is a short description of the new DG-808S as a PDF file:
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Dear Mr. Weber,
I wanted to take a moment to thank you personally for rescuing DG, and for continuing to produce such a high quality glider. I recently purchased a slightly used (240 hours) DG-800S, and I flew it for the first time yesterday. It was an absolute joy to fly. I am nothing like a high-hour competition pilot, nor a test pilot. Just a humble student, trying to get better whenever I fly. I only have a total of 70 hours in 113 flights.
The day was considered "marginal", which is pretty rare in Southern California. I launched, and was the only glider in the sky for the first hour. When I didn't come down, two of the instructors decided to have a mini-race, and fly from Hot Springs to Palomar Mountain. It is only 10 miles, and the race was just for them to kill some time on a slow day. They each launched twice, and both times landed without making that little task. All the while this was happening, I was lazily playing around the clouds that were forming then disappearing in the valley. Because I could spot a new cloud, and run quickly toward it, and pick up the lift it offered before it fizzled out, I was able to stay up over two hours, and eventually came down because I was due back at home.
If I hadn't been in a glider with controls so well balanced, which wanted to go up in the slightest lift, combined with the ability to make very fast runs across the sky, I would never have been able to stay up as I did. I am looking forward to many flights where the 800 will allow me more practice time than anything else out there. That combined with the envious looks I get whenever I pull it out of the trailer, and I couldn't possibly ask for more. It reaffirmed my joy for soaring. I imagine that soon I will owe some of the finest moments of my life, to you personally.
Sincerely,
Chuck Deerinck
N800SX
Evolution to the DG-808S Competition
(reported in Aerokurier 11/2002)
In the future, the pure glider version of the DG-800 18m / FAI class glider from DG Flugzeugbau can be optimally tailored for any weather situation. The substantial increased performance in strong thermal conditions results from raising the maximum takeoff weight by 99 lb (45 kg) for the 15 m configuration and 143 lb (65 kg) for 18 m.
The increased weights of the new DG-808S Competition are achieved through a new ballast system holding up to 61 us-gal (231 liters) of water. The maximum takeoff weights for the DG-808S Competition are 1256.6 lb (570 kg) in the 15 m configuration, yielding in 10.9 lb/sqft (53.4 kg/m2) wing load; or 1300.7 lb with 18 m, yielding in 10.2 lb/sqft (50 kg/m2).
Structural reinforcements in the outer wing section and two additional ballast tanks in the fuselage enabled this promotion to a “tanker aircraft”. The two fuselage tanks not only increase the ballast capacity, they also compensate the CG shift caused by the load in the wing tanks. Each wing contains two independent integral tanks. This innovative tank design improves filling and release times compared to traditional rubber bladder tanks.
The ballast system is subdivided into two independent tank groups, each operated by their own control in the cockpit. The main group consists of the inner wing tanks, holding 15.9 us-gal (60 liters) each, and the forward fuselage tank holding 8 us-gal (30.5 liters). The auxiliary system consist of the outer wing tanks, 9.8 us-gal (37 liters) each, and the rear fuselage tank with 3.8 us-gal (14.5 liters). The fuselage tanks are located directly behind the wing (main group) and in the forward section of the tail cone (auxiliary group).
The DG-808S Competition can be optimally adapted to strong and weak thermal conditions. It retains the excellent climb performance based on the comparable low wing load of approximately 6.2 lb/sqft (30 kg/m2) without ballast, resulting from the larger wing area. In the past this was a disadvantage in strong thermal conditions, compared to gliders from competing manufacturers. With the sophisticated new ballast system, this disadvantage has been eliminated, making the DG-808S Competition particularly interesting for pilots engaged in active competition flying.
For the average DG-808 pilot starting in the weak morning thermals and flying throughout the various conditions of the day, the increased wing load is not of the same significance as for competition pilots (who fly only in the best part of the day.). For these pilots the DG-808S Classic is offered, using the proven ballast system using rubber bladders in the wing with 31.7 or 46 us-gal (120 / 174 liters) and the 1.6 us-gal (6 liters) trim tank in the vertical stabilizer to compensate the CG shift.
Both, the DG-808S Competition and Classic received structural reinforcements of the cockpit to improve the passive safety. They come standard with the so called “Piggot Hook”, which prevents inadvertently unlocked air breaks from extending. Flush-mounted bug wipers and the emergency escape system NOAH are offered as options.
The first DG-808S will ship in time for the Aero convention [in Friedrichshafen, Germany] in spring 2003.
DG-808S shortly before Roll-out.
(reported in Luftsport 08/2002)
DG Flugzeugbau is currently developing a new version of its 15 / 18 m glider DG-800S. The new glider, designated as DG-808S, will be introduced at the AERO 2003 convention [in Friedrichshafen, Germany] and is planned to participate in several competitions during the 2003 season.
The DG-800S was always convincing by its excellent climb performance particularly in weak thermal conditions, when gliders are flown without water ballast. The comparably larger wing area, resulting in a lower wing load, is contributing to this performance. However, in strong thermal conditions, this caused some disadvantage since the maximum achievable wing load was lower than for gliders from competing manufacturers. To compensate this, the maximum takeoff weight of the DG-808S has been significantly increased compared to the 1157.5 lb (525 kg) of the DG-800S. The new weights are 1256.6 lb (570 kg) in 15 m configuration and 1310.7 lb (600 kg) in 18 m configuration. Moderate reinforcements of the wing structure enabled this increase in weight.
DG will offer the DG-808S in two configurations. The “DG-808S Competition” received a unique, innovative ballast system, particularly tailored for competition and record flight conditions. This new system consists of two ballast tanks in the fuselage, and two fully integrated tanks in each wing. The use of integral tank technology significantly reduces the filling and release time for the ballast water, compared to the traditional rubber bladder tanks. This unique ballast system of the DG-808S Competition consists of two fully separated subsystems, which can be filled and released independently. Both subsystems utilize a fuselage tank to compensate the forward shift of the CG caused by the water ballast in the wing tanks. A single control for each of the two subsystems releases the ballast water simultaneously from the wing tanks and the corresponding fuselage tank. The inner wing tanks (15.9 us-gal / 60 liters each) are combined with the forward fuselage tank of 8 us-gal or 30.5 liters; a total of 39.8 us-gal or 150.5 litters. The outer wing tanks of 9.8 us-gal (37 liters) each are combined with the rear fuselage tank holding 3.8 us-gal (14.5 liters), a total of 23.4 us-gal or 88.5 liters. This new system allows a fine tuning of the wing load according to the actual weather conditions.
The “DG-808S Classic” continues the proven ballast system of the DG-800S using bladder tanks in the wing and a small trim tank in the vertical stabilizer to compensate for the CG shift caused by the ballast in the wing tanks.
Structural reinforcements of the cockpit put the latest research on passive glider cockpit safety into practice without sacrifice of space or visibility for the pilot. Flush mounted bug wipers are offered as an option for the DG-808S. These a re similar to the bug wipers developed by DG for the DG-808B.
Standard equipment is the parking break, combined with the “Piggot Hook”. The Piggott Hook is a significant innovation currently only offered by DG-Flugzeugbau. It prevents unintended extension of the air breaks in case they are inadvertently left unlocked. This system was named after the well-known British glider instructor and book writer Derek Piggott, who contributed the original idea.
The emergency escape system NOAH is also offered as an option for the DG-808S.
Maiden Flight of our DG-808S
On Thursday, March 13, our new DG-808S made her maiden flight at our airfield in Bruchsal, Germany. As expected, this was a pretty non-spectacular event, since the harmonic flight characteristics of the DG-800 are well known to Wilhelm Dirks. Nevertheless he was very satisfied with the overall characteristics of his new design.
Increases of the wing load have recently be announced for several glider models since the public presentation of the DG-808S design. However, we like to question how much benefit that is really providing to the average pilot.
Compared to the other gliders in her class, the DG-808S has the largest wing area. With full water ballast, wing loads of 10.9 lb/sqft (53.4 kg/m2) or 10.3 lb/sqft (50,8 kg/m2) can be achieved, as explained above. Other gliders may now even reach a wing load of nearly 12.3 lb/sqft (60 kg/m2), does this make them any better?
We believe that these high wing loads cannot be flown in an optimal way, except in extraordinary strong thermal conditions. Due to the increased wing load the glider has to circle with higher speed, which makes the utilization of narrow thermals nearly impossible and the correct centering in a thermal very difficult, high wing loads might be useful for a top competition pilot, but definitely not in the hands of the average glider pilot.
However, the DG-808S has an advantage which no other glider in her class can provide: With low wing loads she is known to climbs like a balloon. Under weak thermal conditions, as prevailing not only in Europe, all pilots will dump their ballast water. And then the DG-808S flies with a wing load of mere 6.6 lb/sqft (32.4 kg/m2) safely home, while other pilots sit already somewhere on the ground.
… and an avoided out landing can decide the whole result of a whole competition.
Some advice regarding the correct handling at low temperatures can be found here.
The same precautions as for the fin tank apply also to the two fuselage tanks of the DG-808S Competition.
Dear Friedel, dear Volker,
First, thank you very much for finishing the sailplane in time for the “Berlin International” competition, and for my (our) opportunity to fly it there.
The competition has not yet finished and Claus Triebel is still hanging in bravely, but a summary is already possible:
The 600kg (1323 lb) fit the 808 very well. Handling the weight during climb was still fine for me, and I felt no disadvantage to other gliders. Really showing does the weight when accelerating while leavening a thermal, or when pulling up in fast straight flight.
We had during two days very weak thermals in the late afternoon. Without water I had then of course an advantage; and on the second day I was the only one who managed to return.
Filling the wing tanks works very well. For the fuselage tanks I suggest a funnel fixture at the leading edge, so that everything can be done from the front, eliminating the need to walk around the wing. Ideally this fixture should have two funnels to fill both fuselage tanks without switching.
Kind regards,
Ralf
Ralf Fischer and Claus Triebel jointly flew the new DG 808S Competition during the 3rd International Berlin/Luesse Competition, 2003.
They scored first place with this glider.
Congratulation to the pilots!
Translation: Manfred Koethe
From: Jan Walther Andersen
Date: Thursday, August 12, 2004, 5:29:56 PM
Subject: DG808s
Dear Mr. Weber,
Having just returned from Lithuania I would like to express my sincere thanks for the confidence the DG factory has shown me in granting me the opportunity to participate in the European Championships in "808" in the 18 meter class.
The final competition result, i.e. 10th place does in my opinion in no way represent the potential of the DG 808 s Competition.
Some very bad days with a high luck factor resulted in a personal low scoring. However, not one single day and not one single moment I have had any reason to doubt the performance of the glider.
I believe that many fellow competitors found the climbing ability of the "empty" 808 frustrating good - and on the strong days in the end of the competition the 808 showed the great span of performance this glider possesses - being one of the best high speed gliders in the 18 meter field with full ballast.
I will pass on my very positive views on the glider in the Danish gliding community and it is my intention to write a Danish report on the glider giving the DG-808S my absolute best and unlimited recommendation.
I feel confident that the 808 will win future competitions - and I would be happy to take "revenge" in a future FAI contest in the pilot seat of a DG-808S.
Once again thank you - and I wish the DG factory all the best success in the coming years.
Sincerely Yours,
Jan W. Andersen
Denmark
Hello Holger
I would like to thanks you very much that the charter of your DG808S worked out without any problems.
You can read the competition results , daily tasks and different impressions on the homepage www.streckenflug.at/ssm2005.
It was certainly an experiment for me to finish second behind the current world champion Wolfgang Janowitch, considering that my total hours on 18m gliders and also on DG gliders was less than 5 hours. On my first pre-contest flight on Friday the twentieth I flew a distance of approximately 500km. During this flight I unfortunately discovered that the seating position was extremely uncomfortably as I only had sufficient space with the head bent forward.
I therefore removed the original backrest for the next flight and used several cushions instead, and I filled approximately 130 liters into the tanks . This day I flew 900km, but I found that while thermalling with an airspeed of 100km/h the stick pressure, at times, suddenly diminished. I thought that the reason for this was a C of G too far forward which resulted in too high angle of attack of the horizontal plane.
I then looked closely at the tables in the handbook and loaded water into the fuselage tank accordingly. During the contest I slowly was able to get step by step to the optimal position of the C of G. With my weight at 82kg +Parachute+144liters water in the wings+43 liter water in the fuselage the optimum C of G was found. With this weight distribution I was able still to thermal optimally with 95km/h with the glider maintaining its forgiving behavior.
But if I would have wanted to fill the rest to 600kg, I would have had to pack lead into the fin.
My total impression during the contest was that I was facing the other contestants with a fully competitive glider. The final results of this competition would possibly have looked different, if I would not have flown 527km without a variometer ( my father did not fully connect the air pressure tube). But even this day was of great value for me as I had to fly the Glider by the seat of the pants achieving an average speed of 129km/h. You most likely can not have a better practice than this, which again confirmed the excellent handling of this glider which indicated the thermals very well.
I mounted for myself an external Flarm indicator locating the external antenna up front next to the pedal mounting and installed the Flarm below the LX7000 with a cable. The Flarm proved once more to be a necessary safety instrument which I would not like to have missed.
In addition, I could observe the other competitors behind me trying to catch up. I could once more loan a Flarm from our Club for the European championships. But possibly you are already considering to install one yourselves.
With this I close my report and look forward to the European championship.
good flybrations
Eduard Supersperger
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