Red Baron came out with 50 aircraft. Some people would argue that this was more than enough aircraft. Those of us who actually work on it found out different. The air war was an interaction not only between pilots, but different plane types.

:p

If certain plane types are missing, you end up with a skewed perception of what really happened. Leaving the german rotary aircraft out of RB produced a slaughter-fest of the Germans in the game.



History shows that no such activity took place. In fact, the allies got their butts kicked on a regular basis, even WITH a numerical superiority, right up to the end of the war.

Now we can believe that a handful of German aces kicked the Allies in the behind, or we can believe that leaving out certain plane types was wrong.




__________________

You'll put yourself out of work. No ROTJs for KoE?

I am not sure that RBII made any serious omissions with the German fighters.

You mention rotaries. These were failures. The Foker E.IV, D.II, D.III were not suitable for the frontline. By the time the Siemens Schuckert DIII and D.IV arrive, the poor quality of German castor fuel was such that rotaries were not effecive. The only omission here, would be the Fokker E.V or D.VIII. It is not a favorite of mine but, it seems to be expected due to the inordinate amount of depiction it received over the years.

The main fighter omission in RBII is the Sopwith Dolphin. ONly flown by a few units, it was probably the best of the Sopwiths.

I think that some significant recon aircraft should have been included: Caudron G.IV, Voisin L3 and later models, Rumpler C.VII (High Altitude), FE2d (Rolls Royce powered FE2b), LVG C.II, (significant early recon),Junkers J.I/J4, AW FK 8 (Big Ack), DH9, DFW C.V (most numerous German type) and some of the later Albatros C class aircraft.

THe RB plane set is a good starter set. If they had grabbed ten of the above listed, including the Dolphin, I would have been a very happy camper.

Sopwith Dolphin:RB3D WFP...what a beast!!

The Fokker D.II & D.III were built in very large numbers. I have the pics to prove it.

So I'm at a loss as to why you'd think they were unimportant?

They were not successful aircraft. You are essentially looking at two wing-warping bi-planes, one of which had the very heavy twin row Oberusal.

They had a limited time at the front and were quickly replaced by the Halberstadt and the Albatros D.I.

The DII was relegated to Kest duty in Germany.

They were not successful aircraft. You are essentially looking at two wing-warping bi-planes, one of which had the very heavy twin row Oberusal.

They had a limited time at the front and were quickly replaced by the Halberstadt and the Albatros D.I.

The DII was relegated to Kest duty in Germany.

The B.E.2 series was built in even larger numbers. No one would argue that it was a superior plane.

Just because something was built in large numbers doesn't mean it was superior.

Besides, in relative terms all of the early planes had lower production runs. Its not like the early Fokkers were filling the sky.

It would be nice to include these planes in a game, as they do fill a gap between the early Eindeckers and the Halb and Alb scouts. However, suggesting that they would turn the tide against the early Allied scouts is not realistic.

Droops

Well... The people at Aspect face a very interesting challenge. They have to get a reasonable number of important aircraft in-game, with fully detailed cockpits and 3d model, realistic FM and DM and then a nice hi-res skin.

Creating aircraft for KOE is FAR more harder and advanced than creating aircraft in RB3d. I should know, it takes a reasonable ammount of time to create an aircraft for FS-WWI and KOE's models are mostly superior and will sport an even more superior FM and DM system!! (Average about 2-3 months per aircraft, sometimes even longer) I would rather have quality rather than quantity (You remember the original RB3d 3d models, FM and DM don't you? Sure stock RB3d had plenty of aircraft, BUT THEY SUCKED! )

So, If KOE has at least 15 aircraft, modeled realisticly, I will be completely happy! However, I do stress the importance to allow KOE to be expandable the way FS-WWI is. Meaning we can add an unlimited number of aircraft, squadrons, missions, terrains, ground/sea units, and GUI edits. In FS-WWI, there is basicly no limit to what the user community can add. There is no such thing as a "slot"...

The Germans won't get the rotary aircraft that they had in real life, and once again, an unrealistic view of how it really happened up there will be repeated.

I submit that the (continued) apprehension of allowing german rotary aircraft is due to the PASTING the allies would recieve if they were slotted in.

......A pasting that they really got.

Oh well. Another "Errol Flynn" job, worthy of setting my drinks on.

:rolleyes:

Do you have any idea what detailed aircraft I could build under the KOE Platform?

If you haven't seen it yet, go check out my Mercedes Engine for RB.

.....Now times that by 50, and you'd be close.

Rotary aircraft are more manuverable than inlines. So naturally, I can see why some would prefer the germans be limited to inline aircraft.

I have seen that lastest version of your mercedes engine. VERY NICE, i'd like to see it in a beta aircraft soon?

Well... Who's to say the early German rotaries won't get added in? Do you know the final plane-set?

Soon! In fact, I'm working on an Albatros fuselage as we speak!

There's a saying:

"The squeeky wheel gets the grease".

I'm sqweeking, but it's drown out by the sea of sqweeks around me.

So the *real* reason you want rotary kraut planes is so that you can give the allies a pasting. Am I clear on that?

And Front-Line inventories?

Fokker D.II (end of month totals, 1916)
Aug. 10
Oct. 49
Dec. 68
Ordered withdrawn and reassigned primarily to Kesta, training, or Naval duty per Idflieg order of 6 December 1916.

Fokker D.III (end of month totals, 1916)
Aug. 7
Oct. 6
Dec. 34
-withdrawn- (see above)

From 31 August to 31 December 1916, almost half of the biplane fighters at the Front was composed of Fokker D-types.

From Fokker Fighters D.I-IV by P M Grosz, comes the following conclusion:

THE SUMMING UP
In early 1916, by virtue of the impressive victories made possible by his invention of the synchronized machine gun, Anthony Fokker and his monoplane fighter had gained the admiration, trust and respect of the German fighter pilots, whose prestigious Pour Ie Merite decoration made them instant hero-celebrities and provided marvellous Wagnerian funerals. Blinded by the rising Allied losses (labelled in British Parliament debates as 'Fokker Fodder') the Fliegertruppe had opted for more-powerful monoplanes at the expense of biplane fighter development. Caught by surprise at Verdun and on the Somme, the monoplane fighter's days were over. With accurate foresight and to his credit, Fokker had begun to evaluate the biplane fighter in early 1916 apparently without Idflieg financial backing. When called upon, his M 17 and M 18 fighter prototypes stood ready and Fokker received the bulk of the first production orders (see Table 1).

The Fokker company had been presented every opportunity to prove its design skills and manufacturing expertise in creating a series of biplane fighter types, including a 160-hp Mercedes version. But in the race to remain competitive, Fokker and his staff, his engineers and production people, his quality control department and government inspectors - failed miserably. As the above account makes patently clear, the engineering, manufacturing and quality control departments cannot escape the accusation of being slipshod, expedient and remiss, perhaps criminally so, but the air service authorities, respecting Fokker's reputation, may have been reluctant to take action. Fokker as chief executive was ultimately responsible for what occurred, but he was not and never claimed to be a manufacturing expert nor was he a qualified aeronautical1ngenieur. Inasmuch as the Fokker D.I-D.IV fighters were defective, Fokker's engineers and designers, factory supervisors and master craftsmen, had let him down. In my opinion, the head of the prototype metal-working shop, Reinhold Platz (who to the end of his life prided himself above all as an expert welder) must bear responsibility for the poor integrity of the welded structural components.

This bitter episode in the annals of the Fokker works marked the end of the company as a viable manufacturer of combat-worthy fighters for many months. After Kogenluft relegated the Fokker fighters to training service on 6 December 1916, almost a year would pass before a Fokker fighter would once again bask in the limelight of fame. Its reputation tarnished by gross oversight of the most basic manufacturing procedures and quality control practices, the Fokker company was reduced to building training aircraft, namely the Fokker D.V and the AEG C.N under licence. The latter, Tony Fokker claimed, 'made it possible to put my factory on a quantity production basis, with highly profitable results.

From the book Fokker Aircraft of World War One by Paul Leaman, comes the information:

With this proviso, the D.III remained in production but, on 6 December 1916, Kogenluft's embargo on the use of Fokker-built aircraft for combat purposes came into force. All of the D.IIIs in service and those still coming off the production line were either relegated to training duties or sent to home defence units-the Kampfeinsitzer Staffeln (Kestas) and one Naval Defence flight-where they continued to serve well into 1917.

Furthermore, on the most active and numerous of the early Fokker biplanes, Peter Grosz had this to say about the D.II:

Of all the Fokker fighters discussed herein, the D.II had the longest period of front-line service, spanning from August 1916 through August 1917 with a high of 68 aircraft reached in December 1916. The dearth of operational records makes it difficult to establish a niche for the D.II fighter. Driven by a mere 100 horsepower, the D.II possessed only limited combat effectiveness. Many were assigned to units located in less active sectors where high performance was not a factor. A clue to their deployment, found in the Fokker records, shows that of 24 D.II fighters accepted in December 1916, sixteen were sent directly to newly-established Kampfeinsitzer Staffeln (Kesta) based near German industrial cities to provide protection from Allied bombing raids. Eight were issued to training units or naval base defence flights. As of 21 December 1917, a total of 132 Fokker D.II fighters (73 percent of those built) remained in the Fliegertruppe inventory.

To do historical justice to the employment of biplane fighters into the Jasta inventories during the late months of 1916, it would be remiss not to model the inherent airframe defects that the Fokker D.I-D.III series suffered as a result of their poor manufacturing practices!

Yes, we must have these Fokker's indeed!!!

IMHO the biggest miss in RB3D was the lackof an early French recon/bomber. The Caudron was intended but never got in there. The Germans seriously lacked in late war 2 seaters with the 1915/6 Aviatik and Alb CIII soldiering on to the end of the war. The original intent behind WFP was to include these types. Then we added a few more ...

Being serious though, one of the things that WFP does nicely is model changes over time in major types. There is a significant difference between the 150 and 180 HP SPAD VII, a huge difference between the SE5 and SE5a, Fokker DVII and DVIIf, Clerget vs Bentley Camel, etc. If you are fighting a 180 HP SPAD in late 1916 you will be at a significant disadvantage.

Having said that, 50 planes in an initial release is a huge undertaking in a brand new sim. Anybody that complains that "there are only 50" knows zippo about product development. Now ... if only KOE combines the modability of RB with better FMs, improved AI (the is is IMHO the most important thing), and modern graphics we will be in great shape.

Your ability to cut & paste is phenominal, but I'd point out that the early "KEK" airfields were rather few. 120 aircraft back then would be more than enough to last quite awhile.

2 planes in 6 days x 1yr.......What's that? 500+ aircraft?

NO PROBLEMO.

It's interesting, how some people who fly sims, want to see sims with at least 80 to 100 planes flyable.
If you were a pilot on the western front, lets say, 1917, you would have encountered the Albatross scout almost exclusively. Yes, the Germans had other planes, but they were fewer in number. Certainly the Pfalz would have been met, but if you've read World War One pilot accounts, again and again it was the V-strutters they met in combat. The Dolphin, for instance , was a plane, I'm sure, many pilots never saw.
If I were developing a sim, I would rather concentrate on making excellant, realistic models of the airplanes that really affected the outcome of the air war, rather than try and and model eveything that flew.
One of my favorite sims of all time, is Janes World War 2 Fighters. Seven flyable planes. I flew it for years.

VH,

It's called research!

By the way, a KEK (Kampfeinsitzerkommando), and a Kesta (Kampfeinsitzerstaffeln) denote two different unit organizations, they are not interchangeable!

FlyXwire very nice research

Just to follow your lead (for the benefit of interested lurkers) according to John H Morrow Jr's "The Great War in the Air," pg 150...

By June [1916] the German air service desperately needed a new fighter plane....the French Nieuports outclassed the few new Fokker and Halberstadt biplanes reaching the front that month. Boelcke quickly ascertained that the Fokker biplane was too stable for aerobatics, and poor workmanship further impaired the plane's quality."

On page 153 he writes...

By mid-October [1916], of the 885 German aircraft on the Western Front, 540 flew for the German First and Second Armies on the Somme.

He does note that as of 1 October 1916 the German air service had a strength of 210 single-seat fighter out of a total service strength of 1,144 planes plus 423 reserves. You can simply divide the number of Fokker rotary airframes by the number of frontline airframes to get a warm fuzzy on percentages (and perhaps odds of seeing one in combat before they were relegated to defensive missions).

I'd have to research further, but I'd be willing to bet that Boelcke's singular lack of enthusiasm for the Fokker biplanes would have been sufficient to get them withdrawn from (and keep them out of) the newly forming Jastas in the fall of 1916. Boelcke was the man and the September arrival of the new Albatros DI was more significant than rotary Fokkers. Franks' "Jasta Pilots," does indicate that Jasta 2 started out with 2 Fokker DIIIs and a single Albatros DI.

But there is no indication in any of the books on my shelves that the Fokker DII or III made any impact against the RFC in the fall of 1916. If these planes did, then the historians clearly missed it.

Robey

VonHelton, In KOE you wont beable to develope an aircraft fully in 2 days. Trust me... The modeling of even your aircraft in RB3d are no where near the level of model detail in FS-WWI which is no where near the level of detail in KOE! (No offense, RB3d 3d engine can only do so much)

Interesting discussion guys. Maybe some of these questions will never get a 100% complete answer due to the somewhat nonbureacratic nature of the WWI air forces and the scarcity of documentation?

Here's a picture of the Fokker DIII for those (like me) who had never heard of it before:



The site is in Polish, but the image caption suggests it was Oswald Boelcke's plane.

And here's the equally elusive Fokker DII:

Hey Robey..........it's good to read the view from Shoreview!

A backatcha on your research too!

I'll take that challenge!!



I bet I CAN build 2 KOE aircraft in 6 days! In fact, I'm almost sure of it!

True, the first one will have me pulling my hair out, but once I figure out what's what, it's all over!



.

.......And if you got transferred to a squadron that had Bristol Blenheims or P61 Black Widows, you were screwed because the game didn't include them.

NO THANKS



.

In that case, can I offer you a modeling job for FS-WWI???

E-mail me.

hel0695@charter.net



.

The thing is, if the plane was so horrible, why did Bolke fly it so much?



.

Originally posted by VonHelton:
The thing is, if the plane was so horrible, why did Bolke fly it so much?

Define "so much." If he died 28 October and the Jasta started out with 2 Fokkers he didn't have a long time to fly it "so much" n'est pas? Clearly he voiced his displeasure with the Fokker D II and III (performance-wise) and was clearly impressed with the Albatros D I's twin machine guns. If the Fokkers outnumbered the initial batch of Albatros machines then he had to fly something, and there is no idication (that I've found) that Boelcke "lorded" over his selected members of Jasta 2 WRT to which type machine he flew.

You may have different intel on the matter, I've just never read it (don't read german).

Robey

Make two more aircraft for FS-WWI with cockpits and i'll mail you the spare brand new "Four Years of Thunder" that I picked up the other day. I went a little ebay crazy.

Hi guys! I was wondering where all the RB vets were hanging out nowadays.

KOE needs to have rotary engine German a/c included. On one hand, it can't be a proper WW1 aero sim without a Dr.I in the sky. On the other hand, if there is no Dr.I in the sim, how will we be able to complain about the FM being porked?

;-]


LB

Check out the screen shots, particularly the first batch. Plenty of DrI pics, including a cockpit shot which shows that the KOE team is putting the pilot under the wing at the right angle. Not behind it ala RB.

Hey VonHelton, get my e-mail?

Lord Byron, on another KOE board they are claiming the top speed of the Dr1 is 97 mph, making the plane completely worthless, so you can forget the plane being the superior climber that it was.

No doubt, they'll figure out some BS for the Eindekker as well, and the game will be nothing but a slaughterfest on the german side, just like RB is.

I had hoped intelegent minds would prevail, minds that could look beyond allied propaganda, but it appears I was mistaken.

Don't expect the german rotaries to be included, since that would shatter their "Errol Flynn" concept of WW1.

I see now that KOE is NOT the place to get a true experience of what it was like to fly German.

I'm so sick of the propagandist BS, I could PUKE.



.

VonHelton, please state where a publisher/game designer has confirmed any of what you say?

97 m.p.h. was the speed at the aircraft being 9,200ft in the air. If you knew anything about physics, you would know that in early WWI aircraft, the higher up you go, the slower you go. The Fokker Dr.I only had a max speed of 115 m.p.h at ground level. I suggest you do some reading.

Then VonHelton, when are you going to quit propagating it!!!

If the Germans are being massacred in Red Baron, it is almost certainly due to incorrect employment and/or bad AI.

Guys,

Dr.1 performance probably generated more posts on the RB forum than any other subject. It was just amazing. IIRC, the greatest point of controversy was the existence of two different sets of time to climb data, both of apparently good historical provenance, which exist for the Dr.I; one showed climb performance approximately equivalent to that of the Sopwith Triplane; the other showed significantly better performance than the Tripe. Dr.I top speeds have also been variously quoted at anything from 113mph to 103mph to 97mph.

Based upon a comment regarding propellor variants which appeared in a book by the name of THREE WINGS FOR THE RED BARON (published a few years ago), I strongly suspect that the explanation may well be that the Dr.I was fitted with different props over its career - an original one optimized for overall performance and a later one optimized for climb performance. This could also explain the disparities in level speed performance. A prop pitched for optimized climb would cost a few mph in level speed.


LB

Don't waste your efforts. There's a thread on the Western Front Patch forum on Delphi, number 375.1, which has a similar discussion. On that thread, however, the discussion revolves around the Fokker D5.

However, the arguments are the same, right down to the style.

That thread began in August of 2002. No lessons were learned obviously.

Droops

Lord Byron, there is a good chance you are correct. The Germans had been doing sterling work on perfecting the propellor, and had produced some high efficiency designs by the end of the war.
There also could have been some differences in engine. The 700 Thulin Le Rhones the Germans bought from Sweden were fitted almost exclusively to the Dr1s, however there is some evidence that the Oberursel and even some captured Clerget engines were also fitted to some machines. The big problem for the engine argument is the 97mph at 9200ft was measured on a standard Le Rhone Dr1. The Oberursel version would have been considerably less effective.

The high efficiency propellor designs were one of the major causes of problems with the Siemens-Halske ShIII. The prop had to turn at a specific speed for the best results (it also had to be a big prop) and this is the reason for the gearing down of the ShIII. The ShIII was really the final evolution of the rotary and the Germans put a lot of effort into it to wring as much power out of it as possible. It was the only rotary engine with a proper full range throttle, for example. Rotary engines are by nature low compression devices, which is why they cannot produce as much power as an in-line. One relatively easy method of getting more power from the engine is to crank up the compression ratio, but this increases cylinder head temperatures dramatically, so much that the airflow around the cooling fins cannot remove the excess heat. The big big problem with the ShIII was the engine was its high compression coupled with its low rotation speed which caused sufficient heat buildup to cause lubrication failure. Although the ersatz castor oil usually gets blamed, it is now believed that even modern engine oils would not provide sufficient protection. The pilot's handbook talks of the SS DIII as having a very short service life, presumably this refers to the engine as the airframe was sound. It also cautions the pilot not to fly in anything less than perfect conditions and also to avoid cloud and damp when airborne.
The ShIII had so many problems that a Pfalz Dr1 airframe was fitted with an Oberursel engine instead, being designated the Dr2. Presumably the miserable old Oberursel was just too feeble, as the Dr2 was never put into production.

Its funny that you mention the Pfalz Dr.I and Dr.II here. Why, we were having a discussion about those aircraft just the other day over at The Promised Land forum on Delphi. Guess who was involved?

See post 266.110 for the start of that discussion.

Droops

Too much "von-Sniping" on the RB forums.

That's why I'm never going back!!!

Geez, guys, a little civility here!

I wanna know if Von Helton got ArgonV's email!

It's funny, I wasn't sure I'd be able to run this game when it comes out, but with the combined buffoonery of the Dude's computer company and of my ISP (two unrelated incidents) my beloved agreed to the buying of a new system!

So... what IS the planeset in KOE?

Sunscream,

You make an interesting point about compression ratios and heat. This combination of factors might well explain the relatively poor performance of WW1 rotary engine equipped fighters at higher altitudes. It seems that all the good high-alt engines were in-lines.

Another possible reason might be the nature of the fuel induction systems for rotaries which IIUC did not permit the sorts of fine adjustment possible with carbureted in-line engines.


LB

Lord Byron, you are almost certainly correct, again

The lack of a carburetter would have a big impact on high altitude performance. The standard rotary method of getting a fuel mixture to the cylinders was through squirting petrol vapour into the crankcase which would then enter the combustion chamber through a port in the cylinder wall. Air was admitted from atmosphere through another port which would be closed off before the petrol vapour was admitted. On later engines there were separate valves for petrol vapour and air, but it was still mixed with the air in the cylinder, which is inherently inefficient. There was the ability to alter the valve timings slightly, which was the pilot's "fine adjustment."
However, as you ascended the air would thin and hence the fuel/air mixture would become progressively richer. Eventually the engine would effectively choke itself. The fine adjustment can counter this by running the engine leaner, but then the power drops off.

Rotary pistons had to be built light too, due to the centrifugal forces acting on it during its cycle. When at the top of the cylinder it has to move much faster than when it is at the bottom of the cylinder (side pressure). This generates frictional drag, causing heat. Also, the lightweight piston can distort due to heat, which will allow heat transfer (or worse!) to the vapour-filled crankcase without a special flexible piston ring called an obdurator to ensure a seal.
The fault of the Oberursel engine (a licenced copy of the 80hp Gnome) was due to the Germans ignorance of the correct material needed for the obdurator ring. Although they managed to build more powerful versions of the original engine they were very prone to failure as the obdurator ring was not doing its job.

I'm sure Droops will be happy to know that the stupid worm going around has apparently knocked out my AGP slot, so I won't be doing anything until I buy a new motherboard.



.

One of the major reasons that the rotary configuration reached the zenith of it's development by the end of WWI, is due to the fact that the quest for additional power inherently required larger engine capacity and/or rotational speeds. Larger engine capacity and power loads necessitated larger engine componentry and mass, which resulted in greater rotary-torque effect.

However, from an engineering standpoint, it wasn't torque effect that limited the rotary's future, but the problem that centrifugal force imparted to the mechanical operation of the engine's valve-train system. Greater internal capacity, engine mass, and rpms meant that heavier valve-train components (pushrods, valves, rocker arms, etc,) spinning outward with the effects of centrifugal force required exceedlingly heavier counteracting forces to maintain proper operating function (heavier and stiffer valve springs for example). Greater counteracting force generated additional operating friction, which not only absorbed power, but also contributed to greater rotational mass that had to be further compenstated for, literally creating a vicious circle of design compenstation and counter-compensation!

The Siemens-Halske Sh III was designed intentionally for contra-rotation to reduce the rotation speed of the cylinders and thereby reduce the negative effects that centrifugal force had on the engine's valving operation.

Still, increases in weight and design complexity resulted, and the practical limit of rotary engine power/capacity/mass was reached.

Gentlemen,

I've learned more about rotary engine design and peformance issues here than anywhere else. Thank you very much.


LB

Thank you also LORD BYRON.............for adding to this interesting conversation!!!

Eh-hum (clearing throat) This is not actually correct. The INDICATED airspeed is lower do to lower air density, but the TRUE air speed, that is the indicated air speed adjusted for pressure density, will reflect a higher true air speed. Planes do not inherently fly slower the higher they are.

Willi

Point well taken Willi!

Drawing though from the context of the discussion, and concerning the effects that increases in altitude had on the performance of WWI aircraft flying normally-aspirated engines, I'd think ArgonV's statement is generally acceptable.

Eh-hum (clearing throat).............

Re speed versus height.

While it is true that air density decreases with height, it is also true that output of naturally aspirated engines does likewise. According to Hadingham's book, the 96mph figure was "carefully calculated at Rechlin in April 1918". It may well be (and I believe it to be so) that this 97mph value was indeed quoted as TAS.

Another throat clearing from the audience ... ;-)


LB

Eh-hem, Eh-hem (double clearing of throat and slight adjusting of glasses thrown in)

Good counter points on engine out-put at altitiude, but I'm not sure that qualifies as physics.
Now if you told me that gravity contributed to me accelerating when I put the nose down, reaching a fast speed, despite lessened engine out-put at altitude, then that would be physics.

Willi

Willi,

I get extremely nervous when Von Helton and the word "physics" are mentioned in the same sentence. I'm backing out of that one altgother.

However, here is a copy of something Dr.I related which I posted over at the Aerodrome Forum this AM. Perhaps some people here have some interesting comments to offer -

Here are the data which puzzle me. They are taken from Hadingham's book THE FIGHTING TRIPLANES (P159). I'd be interested in your thoughts and comments -

Hadingham's first set of data is of uncertain origin. The altitude datum points appear suspiciously like those I have seen in Bruce's book, BRITISH AEROPLANES, so they may possibly derive from British test of a captured a/c. Because of the non-metric altitude datum points, it does not appear to me to be a German test -

6m 5s to 6560 ft
10m 5s to 9840 ft
15m 15s to 13120 ft
23m 50s to 16400 ft

EDIT - (Well stupid me! These are converted metric height values. There goes my theory!)


Hadingham provides a second set of data explicitly cited as a test of Dr.I 141/17 on 15 Oct 1917 -

1m 36s to 3300 ft (1,000 m)
4m 12s to 6600 ft (2000 m)
8m 0s to 9900 ft (3000 m)
20m 36s to 16400 ft (5000 m)


Without being perfectly explicit, Hadingham intimates use of the 110hp Le Rhone as power in both cases.

The first data set shows climb performance approximately on a par with the Sopwith Triplane, or perhaps slightly better. The second set of data shows considerably better climb performance.

Wing and power loading values of the Dr.I versus Sopwith Triplane are (at least by my amateur calculation) as follows -

Dr.I ........ Sopwith
11.727 ...... 11.854 ..... lbs/hp - power loading
6.386 ........ 6.671 ...... lbs/ft2 - wing loading

The major design distinction between the two a/c is the use of the internally braced thick Goettingen airfoil, yet the Sopwith a/c was 5-15mph faster at any altitude. The question must therefore be posed - why select the Goettingen airfoil?

It is known from NACA data that the Goettingen airfoil offered a much superior L/D ratio at high angles of attack, which IIUC would offer (a) better climb performance, and (b) better near-stall and high angle of attack handling charcteristics. Since the relationship of the first set of Dr.I climb data to that of the Sopwith Triplane is just appropriate to its simple advantages in wing loading and power loading, where would the climb benefits of the Goettingen come into play? I suspect that the first data set may have come from test of a weary captured specimen.

It seems only with the second and better Dr.I climb rate data does the whole issue make sense, assuming that my grasp of the benefits of the Goettingen airfoil is correct. OTOH, all this speculation represents dangerous treading within a scientific field in which I have no true qualifications.

Thoughts anyone?


LB

Thanks for the personal attack, LB.........

VH, I really just want to stay out of the way, OK? You do a lot of really cool stuff. That's great. I'm just opting out of any complicated discussions.

LB

I'll miss ya LORD-BYRON!

Yes, perhaps we should allow VH to discuss his issues by himself!

@Lord Byron

Very interesting post. I was out-of-town this weekend, and it's 01:39 now, so I'm heading off to bed, but I'll give a good look later today.
Have you read the book "Three wings for the Red Baron?" Great read, and a lot of good facts for Dr I fans.

Willi

Willi,

I do have TWFTRB in my library and agree lots of interesting stuff in it. Just wish the author had shown a bit more restraint in the language department.


LB

I'm not going anywhere. It's just that VH and I go WAY WAY back to the RB forum on Delphi, which now seems sadly defunct. VH has done some great work on RB, but let's just say that he holds certain opinions very very strongly and no one will ever change his mind on them. I am not interested in uselessly heating up the airwaves. There is no point in it.


LB

Do, pray tell, what do you mean?

Willi

Bennet is at his best when discussing design and performance issues. But when he addresses narrative history aspects in his book, I get the sense that his editor told him: "Great book, Leon, but a little dry; we need to add a little controversy and excitement." In this respect, I found parts of his prose shading a bit into the purple zone.


LB

@LB

Ach-so, I see. yes agreed. Some parts of the book seemed very much out of character to the overall theme of the work.
Still, a good read with a lot of interesting information.

Willi

Quite agree.


LB

On the subject of the DrI...

For speeds at alt, from German test:

155.8kph at 2780m
148.9kph at 3200m
138.0kph at 4180m

Climb rates: (not exact, extracted from table)

2'34" -3000ft
3'42"- 4000ft
7'50"- 8000ft
13'6"- 12000ft

Willi

Willi,

Thank you. It seems that there is a lot more Dr.I performance data than I knew. Do you have test details? Dates, conditions, etc?


LB

Useful stuff. Thank you, Willi.

The speeds come from NACA TN-147, the climb rate I extracted from the overall chart for WW1 aircraft at NACA.
Lot's o' interesting information there for those inclined to dig deep enough.

Willi

Given the continued rotary engine debate going on, I thought resurrecting this thread was a good idea.

See FlyX's post on page one, and my post later. For reference, a link to the forum thread where this is discussed.

http://forums.delphiforums.com/TheWesternFront/messages?msg=375.1

The thread is an interesting read and should be familiar to others here.

Droops

Le Rhône 80-hp models were made under license in the United States by a Pennsylvania firm, Union Switch and Signal. Oberursel made the 110-hp model, supposedly without authorization in Germany. The Oberrursel U.R. II was a straight copy of the Le Rhône but the Le Rhône was preferred over the Oberursel due to the superior materials used over the home product. However, there were reports in July, 1918 that there was a shortage of Castor Oil which the rotaries required. A new Voltol-based lubricant was substituted and was blamed for a rash of engine failures on Fokker E.V using the Oberrursel U.R. II rotary engine. It has been suggested that without the proper lubricants, the Le Rhône rotary would have been equally failure prone.