Information

Fokker D.VII


Fokker D.VII

The Fokker D.VII was the best German fighter aircraft in service at the end of the First World War. It marked a dramatic return to form for Fokker, the company that had produced the first true fighter aircraft with the E.I Eindecker. The successful monoplanes had been followed by a series of mediocre biplanes, which were plagued by poor build quality, and then by the Fokker Dr.I triplane. This had restored Fokker’s reputation somewhat, but had still suffered from the build quality problems.

The D.VII entered production after the first German fighter contest of 21 January-12 February 1918. Part of Fokker’s success was due to his good relationships with many of the main German fighter pilots, including Manfred von Richthofen. The V.11 prototype performed reasonably well, but lacked manoeuvrability. Fokker was able to rebuild the aircraft mid-contest to produce the winning prototype in the inline engine category and with it a production order for 300 aircraft.

The D.VII combined a conventional steel-tube fuselage with advanced internally braced cantilevered wings, constructed with plywood ribs, covered in fabric and with plywood leading edges. The ease with which the simple fuselage could be maintained was one of the reasons the type was adopted.

The German army realised that Fokker did not have the capacity to build enough aircraft for their needs, even after an order for AEG C.IV trainers being built under license was cancelled. To solve this problem, Albatros and OAW were given contracts to build the D.VII under license, paying Fokker a 5% fee. Of the more than 3,000 aircraft ordered, only 1,000 were produced by Fokker.

The prototype D.VII was submitted for type tests on 4 February 1918, passing easily. An early production aircraft was tested in March, and passed with only one modification. The D.VII (and D.VI) did not suffer from the problems of build quality common to most other Fokker aircraft of the period, possibly because Fokker was aware that his own products would be directly compared with the license built aircraft – if the Fokker produced aircraft had been flawed in the same ways as the earlier biplanes, it is perfectly possible that Fokker might have lost the contract to produce his own aircraft! The only serious problem that developed with the type was caused by over-heating ammunition, which exploded causing several fatal fires. This problem was solved by adding extra engine cooling louvers, some at the factory and some at the front line.

During its production run the D.VII was powered by a variety of engines. Very few used the original Mercedes D.III 160hp engine, replacing it with the D.IIIaü, capable of producing 180-195hp. The best version of the aircraft was the D.VIIF, powered by the over-compressed B.M.W. D.IIIa engine, capable of 185hp. These aircraft were preferred by the pilots, but were never available in sufficient numbers. All types of D.VII were popular with the German fighter pilots. The aircraft handled well and had light controls that made it less tiring to fly than many of its contemporaries. At medium altitude it was faster and more manoeuvrable than its opponents. It accelerated quickly in the dive while remaining steady, making it a good gun platform.

The D.VII began to appear at the Jastas (front line fighter squadrons) in late March and early April 1918. The first unit to be equipped with it was Jagdgeschwader I, under Manfred von Richthofen, although he appears not to have flown the type in combat. The number of aircraft at the front increased rapidly, from 19 on 1 May, to 407 on 1 July and 838 on 1 September. Rather than equip entire units with the new aircraft, Jastas received piecemeal deliveries of the D.VII as aircraft became available. The best pilots in the best units were thus the first to receive the aircraft. As a result many German aces achieved great success in the D.VII, but at the same time less capable or new pilots were given discarded older aircraft, and suffered high casualties.

By the end of the war the D.VII had been the main aircraft for forty seven Jastas (fighter squadrons). The type equipped Jastas 4, 6, 10 and II in Geschwader I, Jastas 12, 13, 15 and 19 in Geschwader II, Jastas 2, 26, 27 and 36 in Geschwader III and independent Jastas 5, 7, 8, 14, 16, 17, 20, 22, 23, 24, 28, 29, 30, 32, 35, 37, 40, 44, 46, 47, 48, 49, 51, 52, 53, 54, 56, 57, 58, 59, 66, 69, 71, 79 and 80.

The Fokker D.VII had an edge over all of the main Allied fighters of 1918. However, it appeared too late in the war to have any real impact on the fighting. German’s best chance of a victory in 1918 came during the Second battle of the Somme of 21 March-5 April. The D.VII was beginning to enter service in tiny numbers as this attack ground to a halt. As the end of the second German offensive, the battle of Lys (9-29 April), there were only 19 D.VIIs in service. By 1 July, when the type was finally available in reasonably large numbers, two more German attacks had failed (third battle of the Aisne, 27 May-3 June 1918) and the Noyon-Montdidier Offensive (9-13 June 1918). The Fokker D.VII was an aircraft of the period of German defeat.

In its relatively brief front line career, the D.VII won itself a very impressive reputation. Famously it is the only aircraft mentioned by name in the clause of the armistice agreement that called for the surrender of 2,000 German aircraft. Of the aircraft surrendered, 324 went to Belgium as war reparations and 142 to the United States.

Stats
Span: 22ft 3.5in
Length: 22ft 11.5in
Armament: Two fixed forward firing 7.92mm Spandau machine guns

Mercedes D.III powered aircraft
Horsepower: 160
Max Speed: 118mph

BMW IIIa powered aircraft
Horsepower: 185
Max Speed: 124mph

Books on the First World War |Subject Index: First World War


Building an Airdrome Aeroplanes Fokker D.VII

The Experimental aircraft community is blessed with a plethora of designs that captivate the interest of builders regardless of mission requirements. My first two projects were designs that reflected a love of relaxed aviation at low altitudes and airspeeds. Subsequently, the restoration of a 1940 J-3 reinforced the love of vintage-style aviation, but my third homebuilt, an RV-6, was an excursion into a very different corner of the performance envelope. Since 1999, the RV-6 has served admirably as a transport to far-flung areas of the country and, even more impressively, a portal into the wonderful and vast community of RV owners.

Fokker D.VII in a box. The kit falls somewhere between a complete kit and a pure materials kit.

But the low ‘n slow urge is difficult to suppress, and a few years ago a plansbuilt Legal Eagle XL emerged from my shop [see “Legal Eagle XL,” January 2013]. The Eagle, an ideal complement to the RV-6, was enjoyed over the course of four summers before passing on to a new owner. However, building fever is a difficult affliction to shake, so the search was undertaken for a new project to occupy the shop. This series of articles is about how I selected a new project based on my priorities, proceeded to build the aircraft in a relatively short period of time, commenced flight tests, overcame serious issues with the airframe, but ultimately achieved my goal of a unique, enjoyable Light Sport Aircraft.

What aircraft would be a good companion for the RV-6 that resides in my hangar and would possibly close the loop on my building journey and leave me with an LSA-eligible aircraft? Low ‘n slow, yes, but this project could be something a bit different from what is customarily seen on the local airport ramp. A craft suitable for traveling isn’t needed, and I am content to enjoy late evening flights while flying solo. A highly fabricated or quickbuild kit was not necessary to find a place on my list of prospective projects because I have built two aircraft from plans and enjoy the challenge of solving construction details that often occur when building from plans.

The tube-and-gusset method of assembly only requires simple tools and results in a light, rigid structure. The turtledeck is one example of an area of the airframe that is undocumented in the plans and left to builder discretion. I added plywood formers to support the stringers.

My decision tree for this project was not unlike scores of other builders who have flipped magazine pages, surfed websites, and roamed airshow grounds. Tire kicking is fun and low risk, but at some point branches on the tree need to be finalized if a project is to become reality. I hope the exploration of my priorities during this process will offer assistance to those considering entry into the wonderful community of Amateur-Built aircraft. Informed decisions are the key to an enjoyable project that results in an aircraft that meets anticipated needs. But an enlightened builder should also realize unexpected hurdles can appear in even the best thought-out plans.

Few projects are considered without calculation of cost verses available budget. Even though budget ceiling was not a major consideration for this project, I still wanted to hold total expenditure to an amount where I would be comfortable, considering it more as a “toy” than a significant investment. I realize this is a relative number and dependent on a builder’s station in life, but most aircraft builders are looking for a magic carpet that can be incorporated into a family budget without creating domestic tension. This is a critical aspect of project selection—lack of family support can not only lead to less enjoyment of the build, but possibly more serious relational repercussions.

Plans builders spend much time visualizing possible solutions to construction details. Here the mental gears are slowly grinding while searching for a means to secure the fuel tank within the fuselage while still allowing it to be removed from a finished aircraft.


Kit Arrival

After gestating in Robert Baslee’s shop for six weeks, a 12-foot-long, 530-pound crate arrived at my local freight terminal. I elected to take delivery at the terminal instead of having to arrange meeting a driver at home, and the crate easily fit in an open 12-foot U-Haul trailer. Upon arrival at my shop, removal of a couple dozen screws revealed an interesting assortment of…airplane stuff. Easily identified were wheels, wheel covers, cowl nose bowl, fuel tank and a document package. But the real bones of the kit were apparent after digging deeper into the box. Dozens of 6061 aluminum tubes comprised the majority of the shipment. There were several large plastic bags labeled for individual subkits containing gussets, hardware, and fittings. Fortunately, every item was tagged with a sticker bearing a coded number associating it with a subkit.

I found a free protractor app on my phone to be as useful as a high-dollar digital level. The fuselage spar carry-throughs must be located with precision because they establish wing straightness and incidence, and are key to building a properly rigged airframe.

It is necessary to build simple bending fixtures so tubing for the fuselage, empennage and wing ribs can be shaped as necessary. Patterns for these fixtures are included in the document package, so particleboard, salvaged from the shipping crate, was cut to shape and attached to the workbench. The aluminum tubing can be smoothly bent cold if care is taken to form each bend in small increments. Attempting to bend tubing too aggressively results in kinks (aka wind chimes) and ordering fresh tubing.

The fuselage and upper center section are very carefully leveled in preparation for fabricating the cabanes that attach the upper wing center section to the fuselage. Accuracy is critical in achieving an airframe that is straight and properly rigged.

The first evening was spent exploring the document package, which includes a build manual, a set of drawings, and two DVDs with photographs and a video. Surprisingly absent from the package was a materials list with which to verify the shipment was complete. It would be possible, but very tedious, to make a detailed inventory by picking apart each drawing and matching it with the pile of parts, but I decided my time was better spent elsewhere. However, several times in the project I wished an early inventory had been practical because of shortages that were discovered as the build progressed. Robert Baslee was usually prompt about shipping needed parts, but I would have preferred not needing to call attention to the omissions.

Poster-board mock-up assisted with determining the final configuration of the prototype cowl. Exhaust stacks are Aeronca Champ with no modifications.


Fokker D.VII

When the aircraft appeared on the fighting front in April of 1918, Allied pilots at first underestimated the new fighter because of its squarish, ungainly appearance, but quickly revised their view. The D.VII’s had the unique ability to seemingly “hang on its propeller,” and fire into the unprotected underside of enemy aircraft which made it a feared combat opponent. The final Armistice agreement specifically demanded that all Fokker D.VII’s be immediately surrendered which attested to the generally high regard for the airplane. In response to the loss of air superiority in late 1917, the Germans organized a competition for new fighter designs held in January 1918. The winner was the Fokker D.VII with Fokker receiving an order to build 400 aircraft. The airplane was a single-engine, single-seat, biplane initially with a 170-180 HP Mercedes D.IIIa water-cooled engine. Later aircraft were fitted with 18-200 HP engines. (c)Philip Makanna/GHOSTS

Full size restored Fokker D.VII in flight

Germany produced about 3,300 D.VII aircraft in the second half of 1918. This was accomplished through the use of multiple manufacturing plants. The airplane was noted for its high maneuverability, ability to climb at high angles of attack, remarkable docile stall, and its reluctance to spin. The favorable characteristics resulted in the aircraft being credited in turning a mediocre pilot into a good one, and a good pilot into an ace! Wingspan 29 feet 4 inches Length 23 feet Empty Weight 1540 lb. Gross Weight 1936 lbs.


Fokker D VII

With its strong climb performance and good flying characteristics, such as resistance to tailspin and excellent manoeuvrability, the Fokker D VII was among the best fighter planes in the First World War. By the time of the Armistice on November 11, 1918, more than 760 planes were built and deployed to 48 German fighter squadrons. The Fokker D VII was highly respected by the enemy. It was the only plane explicitly mentioned in the Armistice agreement. Every plane of this type had to be turned over to the Allies.

The plane on display was flown by the Dutch navy (MLD) until 1935. It has a few modifications to distinguish it from the planes flown in the First World War. For instance, the fuselage fairing in front of the cockpit was changed, and the plane does not have the typical weaponry of a fighter, consisting of two machine guns above the engine. The paintwork shows the typical camouflage markings of German aircraft in the First World War, and the serial number is fictional. The plane was found in Bavaria in 1948 and has been part of the Deutsches Museum collection since then. The individual history of the artifact between 1935 and 1948 is not known.


Fokker DVII Build Story


T here are as many reasons for taking on a project as there are methods to complete it. In the case of movie props. one source is the original article, another is to build a replica. Time constraints and deadlines sometimes dictate the style and construction methods. In the case of the Fokker DVII built for “The Blue Max” film. We can safely say the aircraft was built to an airworthy standard in a very short period of time! At the Vintage Aviator Ltd we are responsible for the operation and maintenance of a number of WW1 aircraft, including the Fokker DVII built in France for the 1966 film “The Blue Max”. The original constructors of this machine, Rousseau Aviation, Dinard Airport France, did a marvelous job at creating a flying aircraft replica for the film, however years of use and several owners later have taken it’s toll. This aircraft was airworthy when it arrived here in New Zealand but we wanted to restore it and add more details that would make it a more accurate replica.

After having flown the DVII for several hours here in NZ we became aware of its shortcomings rather quickly, it just didn’t perform like the legendary fighter it represented. The airplane was heavy and the engine seemed a bit tired and the fabric covering was clearly a quick attempt at “fake” printed lozenge. Each pilot that had the chance to fly it liked it, but all made the same general comments “It feels heavy”, “It wont climb”, and “I cant catch the SE.5a or the Camel”.

Face Lift

T he decision was quickly made to give the DVII a bit of a face lift. After all of our airshow commitments had passed we started to disassemble the aircraft and see what could be done to improve its performance and looks. Since this airplane is a replica that doesn’t use an original engine nor original construction we had a great deal of leeway on what we could do.


In all fairness to the original constructors, this aircraft has been around for a while and has been used in several films, it served it’s purpose and did a fantastic job. The sheer fact the airplane has been in service for nearly 45 years could add to it’s lack of performance, propellers have been changed, the engine was starting to get tired, repairs have been made and the airframe was getting heavier as planes seem to do when they age! With the dismantled aircraft in our workshop we could remove the fabric and inspect all of the individual components. The construction slightly different to the original, ribs are made of thin plywood and the spars appear to be solid laminated lengths of spruce. The trailing edge has been cut out of timber rather than the original wire trailing edge that gives many Fokker aircraft that distinctive “scalloped” look. Wing tip bows are made of massive chunks of ash that have been steamed to shape them. In an effort to make sure this aircraft was back in the air before too long we set a deadline to “return it to service” so that we didn’t end up rebuilding everything or spending too much on it! It was quickly determined that the wings were in good shape and only minor repairs were needed. We removed some weight from the wingtip bows and sealed the entire structure to protect it from moisture.

Materials


W hen building any aircraft raw materials are of prime importance. The selection of materials based on strength weight and availability. It became apparent that during the construction of the DVII the selection of materials to build the aircraft out of must have been strongly influenced perhaps dictated by the time frame. For instance the decision to make “streamlined tube” out of several round tubes had to have been because the builders could not source appropriate sized streamlined tube in a hurry. This method of construction added a huge amount of weight to the plane and was far more labor intensive. The cabane strut “tripods”, interplane struts and landing gear struts were all built up of many pieces of tubing rather than single streamlined tubes. These make shift streamlined tubes were built up of at least two whole round tubes of different sizes and then tacked together with two more sections of round tube split in half! Each conglomerate of steel tubing was then wrapped with fabric to give it a finished streamlined airfoil shape. These parts alone were several times heavier than a similar part made out of a single sreamlined tube. In order to replace these built up struts we positioned the overhauled wings in place on the fuselage and rigged the airplane, partially fabricating the new struts in situ.

Remaking Authenticity


T he tail surfaces were also constructed out of materials that deviated a great deal from the original. Since many sets of drawings and much research has been made into the Fokker construction it would be foolish to imply the builders were simply not aware of the original construction. The original constructors also mentioned that they had access to one of the surviving original Fokker DVII’s housed in the French Musee de l’Air at Chalais Meudon. Once the tailplane was stripped of fabric we decided to see why it was so heavy. We have already restored seven Fokker Triplanes and have a tremendous experience with Fokker tailplanes. The DVII tailplane just felt wrong! The easiest way to check the material would be to cut into it and see how thick the steel tube was. after one slice we discovered it was more like pipe!


This would explain the huge lead weights attached to the engine mount, these were needed to counterbalance the heavy tail and maintain a reasonable center of gravity. We were shocked when we removed the weights and set them on our scales. The two weights totaled nearly two hundred pounds! Part of this was necessary to compensate for using a lighter more modern air cooled engine, a gipsy queen, instead of the heavier liquid cooled Mercedes engine which would have originally been used.


A new tailplane was in order, some parts were reused and incorporated into our new chromoly structure. While we were working on the tail section we decided to install a proper tailskid in place of the tailwheel that was fitted. We knew that a tailskid must have been installed when the airplane was built, it appeared in the film with one, and all the mounting points and bungee attachments were already in place. Fitting a tailskid was easy.

Structure


M oving forward from the tail, we found the structure to be well preserved and in incredibly good condition, all that was required was stripping the paint and removing some unnecessary turnbuckles. The Fokker style fuselage is of welded steel construction, having wire bracing in each “bay”. In this replica each wire brace had two turnbuckles, we elected to liberate some of these turnbuckles for future use elsewhere and to reduce weight once again. The steel structure was stripped and repainted and all new hardwire bracing installed with half as many turnbuckles. The floorboards were heavy old oil soaked fiberboard that was beginning to delaminate so we replaced these with aircraft plywood and thin aluminum “heel plates” to help prevent the wood from wearing away. The seat, control stick assembly and rudder bar was a complete unit removed from a Stampe biplane, this unit was restored and reinstalled after minor modification to the brake master cylinders.

Accessories


I n an effort to make the DVII look more authentic we installed a set of our reproduction aircraft guns, in this case LMG 08/15 “Spandau” machine guns. We removed the makeshift windscreen and added ammo chutes, fuel gauge, fuel filler and various doors and access panels that an original aircraft would have. Again to our amazement, this airplane had a huge fuel tank entirely made out of steel turn plate, it weighed a ton. We decided to make a lighter aluminum tank with a slightly smaller volume, this even gave the pilot more room for his legs.


Forward of the firewall we focused our efforts on cleaning up plumbing and wiring since the engine installation was functional and in fairly good order. Upon inspection only a few brackets showed distress form years of service, these were repaired by welding or replaced and the newly overhauled Gipsy queen set in place so that new cowlings could be made. The replica already had slightly modified cowls to hide the modern engine and disguise it looks, these could be improved on. We chose a late model Fokker Built aircraft to replicate, this necessitated making new cowlings with proper louvers and a reshaping of the fiberglass nose bowl.

Heavy Steel Landing Gear

T he last major item to overhaul was the landing gear. Like everything else, this was heavy and made of steel. Original Fokker landing gear was carefully designed to be both strong and lightweight. Instead of the original style riveted aluminum box section this landing gear was made of Steel with access holes cut with a torch! Now it may not have been pretty but it sure worked well. The entire landing gear and axle assembly was replaced and as a result a weight savings of nearly sixty pounds was realized. After building the more authentic Fokker style landing gear one could see why a simpler version was used, the aluminum box section was difficult to construct and certainly took much longer than the simple welded version, and in the end it is completely hidden by the large fairing between the wheels.

Only with a replica aircraft could we have the leeway to experiment with restoration and reconstruction on this level. However, with the time constraints involved, TVAL had to discover methods of reconstruction that wouldn’t involve total rebuilding and painstaking hours of work. With the overall facelift that the Fokker DVII received, including quite a drastic weight loss with the tailplane, fuel tank and landing gear replaced, we became confident that this would increase the aircraft’s performance in the sky, not to mention more leg-room for the pilot! Now with brand new Spandau guns and printed fabric replacing the previous painted lozenge, the new Fokker DVII is surely close to it’s former glory as a renowned fighter of speed and maneouverability, surely capable of once again catching the Se5a and the Camel.


Fokker D.VII - History

Industry/ Capability:
In the 1920s, Fokker became the world's largest aircraft manufacturer.

Head Office:
1912: Fokker erected two aircraft factories in Germany, one in Johannisthal (near Berlin) & one in Schwerin.
1919: Fokker relocates & builds factories in Amsterdam & Veere.
1922: Fokker also builds three factories in the United States.

Noteworthy:
Fokker Dr.I triplane
Fokker D.VII
Fokker E-V/D-VIII .
* partial list

Fokker was named after its founder, Anthony Fokker.

Fokker aircraft have played a significant role in the history of aviation. Innovative designs and construction techniques kept Fokker companies at the forefront of aircraft design and manufacture for nearly ninety years.

This is a real blueprint, expertly restored from original plans and vintage design drawings. — measuring a generous 42"x 30".

The Fokker E.V was the last fighter type built by Antony Fokker for the German Fliegertruppe during WWI. The aircraft was a plywood-covered, fully cantilevered parasol wing configuration.
The E.V was just in time for the Second Fighter Competition (July 1918). The Plane was regarded as the best of the rotary - engined competitors. Production started immediately, and in July the first. continues below

Right: The Fokker D.VIII has the distinction of recording the last air kill in the First World War and was often referred to as 'The Flying Razor' by the Allies.

Anthony Fokker ended the War as he started, with a monoplane design. Unlike his earlier 1916 Fokker E-III "Eindekker?, this one had a cantilever wing and had no external bracing wires. It combined survivability, firepower and adaptability in a sturdy airframe.


Left: Fokker D.VIII in Dutch markings
The Fokker E.V was the last production fighter of the German Air Service in 1918. It had a troubled start with the problem being traced to poor workmanship in the wing manufacturing shops of the Fokker subsidiary. When gussets and webs were installed correctly, the plywood covered wing of the E.V met and exceeded required specifications.

Redesignated as the D.VIII, ( some late examples still labeled as E.V) the type soldiered on even after the end of World War One. It was fleshing out infant air forces in other countries, outwardly they were indistinguishable except by their stenciled serial numbers. In 1918 it was the cutting edge.

Fokker D.VIII/E.V

The Fokker E.V was the last production fighter of the German Air Service in 1918

The Fokker E.V was the last fighter type built by Antony Fokker for the German Fliegertruppe during WWI. The aircraft was a plywood-covered, fully cantilevered parasol wing configuration.
The E.V was just in time for the Second Fighter Competition (July 1918). The Plane was regarded as the best of the rotary - engined competitors. Production started immediately, and in July the first production planes were delivered to the Front. The performance was impressive and pilots nicknamed the plane the "Flying Razor". But after two flying accidents on August 16 and 19, when a wing failed in flight, the type was immediately grounded for investigation. Production was stopped, and all previously made E.V's were returned to the Fokker factory.
The wing structure was strengthened, and workers were more careful with assembly procedures.

The aircraft returned to the front during October as the "Fokker D.VIII". The letter D, which used only for biplanes, indicated that the new wing was twice as strong. But the D.VIII came to late, because the war was ending. Only one victory, achieved by a pilot flying the E.V, had been confirmed the victory awarded to Emil Rolff from Jasta 6 on August 17.

The myth that Fokker smuggled train-loads of aircraft out of Germany, has reached epic proportions. While we know that this was true to some extent, we must try to understand what was happening. First, we know that Germany was out of the aircraft purchasing market after November 11, 1918. It is known that of 335 that were ordered, 289 Fokker E.V/D.VIII had been delivered by 8 Oct.1918. Pending contracts could not be paid for, so the post war German government was more than willing to let Fokker leave with his rolling stock of D.VII, D.VIII and C.I types (some of these having been accepted by the German government were among those spirited away).

It's military service continuing after the end of WWI. Eight (four from other sources) E.V's from the Polish Air Forces flew against Russian and Ukrainian forces in 1919. One of these planes was captured by the Red Army and used by the Soviet's until the mid 1920's.
Some planes reached Holland, Italy, Japan, the USA, and England as trophies, in total all the E.V's/D.VIII's were scrapped in accordance with conditions set forth in the Armistice.

The allied commission was busy destroying aircraft in the field. New aircraft at air parks ready for disbursement went to the allied countries as war reparations (mostly Fokker D.VII and Roland D.VIb types). At least twenty incomplete Fokker D.VIII type airframes were destroyed at the Fokker factory in Schwerin. A further twenty-six complete Fokker E.V/ D.VIII types went to Holland and were sold off by the Fokker company there. Recipients were the Dutch Luchtvaart Afdeling , Polish Air Service and The United States.

D-VIII EQUIPPED WITH 110 H.P. OBERURSEL ENGINE.
OFFICIAL PERFORMANCE TEST-SUMMARY OF RESULTS

May 20, 1921 - Airplane: Fokker Monoplane
No.: P-165
Type: D-VIII
Engine: 110 H.P. Oberursel
Propeller: Axial 01476
Equipped as: Alert type
Weight empty (including water): 848 pounds
Armament and equipment: 74 pounds
Crew: 180 pounds
Gasoline: 113 pounds
Oil: 23 pounds
Weight loaded: 1,238 pounds
Weight per square foot: 11.45 (108 square feet)
Weight per horsepower: 9 (137 H.P. at 1,390 R.P.M.)

Over-all span: 27 feet 7 inches
Over-all length: 19 feet 4 inches
Over-all height: 8 feet 6 inches
At rest: 5 feet 8 1/2 inches
Chord: 4 feet 11 inches
Area with ailerons: 108 square feet
Arrangement: On trailing edge of wing
Upper length: 5 feet 2 1/8 inches
Upper chord: 10 3/8 inches
Distance from center of ailerons to longitudinal axis of airplane: 10 feet 3 1/2 inches
STABILIZER: Setting: 3.5 deg positive


Classic German fighters – The Fokker D VII

The Fokker D VII was without doubt the finest fighter placed in large-scale production and service by Germany in the course of World War I, and was arguably the best fighter produced by any of the combatants in that war if one makes allowance for the difficulties encountered by German industry in producing aircraft and engines in the closing stages of a lost war, and for the difficulties faced by the Imperial German army air service in operating a capable fighter with steadily declining quantities of increasingly indifferent fuel over the same period.

The weights and performance of the D VII were thus very varied depending on a number of factors, but despite this and also the fact that the type was generally faced by Allied fighters with somewhat greater power available to them, the D VII nonetheless did more than just hold its own, and became so feared that it was the only German warplane specifically mentioned in the Armistice agreement that ended World War I in November 1918, when the Germans were instructed to hand over all surviving examples of the D VII. Moreover, the influence of the D VII lasted well beyond World War I for many examples were kept in service after the war and, more importantly, Allied assessments of the type’s technical features and operational capabilities had a considerable effect on the design of fighters into the middle of the 1920s, especially in the USA.

Origins of the D VII
The origins of this seminally important fighter can be traced to the middle of 1917, when the German authorities announced that a major competition would be held at Adlershof near Berlin in January and February 1918 to find two types of new standard fighter for the Imperial German army air service, one of them with the well established Mercedes D.III water-cooled six-cylinder inline engine and the other with an air-cooled rotary engine of a type not yet specified, although the front runners were a pair of 11-cylinder units each rated at 160 hp (119 kW), namely the Oberursel Ur.III, which was preferred by Anthony Fokker as he had a major interest in the Oberursel company, and the Siemens-Halske Sh.III. The commercial as well as military importance of winning the competition were not lost on German manufacturers, and this resulted in a flurry of design and development effort by many German aero manufacturers including Fokker, which had fallen behind other companies in the securing of major fighter orders since its epoch-making E-category monoplanes and early ‘D’ category biplanes in 1915/16.

The competition rules called for assessment of the aircraft (27 machines were ultimately submitted by 10 manufacturers for evaluation against four standard Albatros D Va fighters) in terms of their general flying characteristics, combat capabilities, manoeuvrability, diving qualities, pilot’s fields of vision, level speed at 16,405 ft (5000 m), and climb to 3,280 and 16,405 ft (1000 and 5000 m).

Designed by Reinhold Platz
Anthony Fokker entrusted to Reinhold Platz the task of creating the new fighter prototypes he intended to enter in the competition, and one of these was the aeroplane known to the company as the V.11, which was designed in parallel with the rotary-engined V.9 as a slightly enlarged development of this machine with the Mercedes D.III engine driving a two-blade propeller of the tractor type. Fokker decided to build two of these V.11 prototypes, and the first of these flew in December 1917 as a machine that was clearly of close relationship to the V.9 despite its inline- rather than rotary-engined powerplant and slightly less obvious features such as wings of greater chord (requiring the adoption of a two-spar structure for the lower wing in place of the V.9’s single-spar arrangement), N-type interplane struts in place of the V-type struts used in the V.9 but replaced by N-type struts in the D VI production model, and cabane arrangement of two tripod forward struts and two rear struts in place of the arrangement of four shorter tripods used in the V.9 but replaced by the V.11’s arrangement in the D VI production model.

Initial trials of the V.11 revealed a number of poor features including poor directional and longitudinal stability that was improved by a lengthening of the rear fuselage by some 1 ft 3.75 in (0.40 m), the resulting rearward movement of the centre of gravity also requiring the rearward movement of the upper wing in a fashion that reduced the wing stagger and required the modification of the upper-wing centre section with a cut-out over the pilot’s cockpit. The V.11 was initially flown with the same type of tail unit as the V.9 (horizontal surface with horn-balanced elevators incorporated within its basically triangular shape and vertical surface comprising only a horn-balanced rudder of the ‘comma’ type) but was later revised with elevators whose balance areas broke the straight line of the leading edges and a new vertical surface with a small triangular fin carrying a horn-balanced rudder.

In this revised form the V.9 emerged as the clear choice of the front-line pilots selected to undertake the flying elements of the trials, and the second V.9 was completed to this standard as what was in effect the production prototype of the type. As it had also demonstrated exceptional dogfighting capabilities, including excellent agility at high altitude, the ability to turn at high altitude without losing height and the facility to hang on its propeller while under full directional control, the V.9 was therefore ordered into large-scale production for service as the D VII.

The required quantities were beyond Fokker’s capabilities, and it was a matter of great satisfaction to Anthony Fokker that his company’s main rival in the design and manufacture of advanced fighters, namely the Albatros Werke G.m.b.H., was ordered to produce the D VII at both its main plant and also in that of its Ostdeutsche Albatros Werke subsidiary. The front-line pilots did have a number of criticisms of the V.9, it should be noted, and these included too great a structure weight, slightly inadequate performance at high altitude, and climb performance that was not as good as the pilots would have liked: the pilots therefore recommended that the D VII production model should have the new BMW IIIa water-cooled six-cylinder inline engine rated at 185 hp (138 kW) but, as the Inspektion der Fliegertruppen (inspectorate of flying troops) pointed out, this new engine was still under final development and would not be available for some six months and that the D VII would have to make do in the short term with the Mercedes engine. This provided adequate performance at medium altitudes and, as had often been pointed out by front-line pilots, this was generally preferable to an exceptional climb capability.

D VII features
The D VII was an unequal-span biplane typical of Platz’s overall design philosophy as modified to create a biplane rather than monoplane type and as adapted to the availability of current material and production resources. The aeroplane was therefore based on a mixed structure (welded steel tube for the fuselage and tail unit, and wood and plywood for the wings) covered largely with fabric, and a wing cellule based on Platz’s firm belief in the superiority of thick-section wings for great strength in combination with high lift at the moderate speeds of the day. The aeroplane was based on a fuselage of welded steel tube construction. This fuselage was of rectangular section with a rounded upper decking and carried, from front to rear, the powerplant, fuel and oil tanks, open cockpit, and tail unit. This last was of fabric-covered welded steel tube construction and comprised single horizontal and vertical surfaces: the former included a large tailplane with acutely swept leading edges and a single strut on each side bracing it to the relevant lower longeron, and this carried the plain elevators and the latter included a triangular fin carrying a horn-balanced rudder that was hinged at its lower end to the vertical knife-edge in which the fuselage terminated.

The staggered semi-cantilever wing cellule was of fabric-covered plywood and wood construction with a covering of fabric except over the plywood-covered leading edge, and comprised a larger upper wing and smaller lower wing each of constant chord but tapering thickness to its slightly rounded tips large horn-balanced ailerons were installed on the outboard ends of only the upper wing’s trailing edge. Both surfaces were flat and built as single units of the cantilever type: the lower wing extended from the fuselage in line with the lower longerons, while the upper wing had a shallow cut-out in its trailing edge above the cockpit and was carried above the fuselage by a cabane arrangement comprising two tripods at the front and two single struts at the rear. The upper and lower wings were separated on each side by a single set of N-type interplane struts that obviated the need for incidence-bracing wires, and there were no flying or landing wires. The airframe was completed by the landing gear, which was of the fixed tailskid type with a main unit of the through-axle type in which the two-wheel axle was bungee-bound into a spreader bar arrangement faired to an aerofoil section with plywood and carried at the closed ends of two wire-braced V-type struts extending downward and outward from the lower longerons.

As noted above, the powerplant was based on one Mercedes D.III engine: this was installed at the front of the fuselage inside a louvred light alloy cowling that left only the top of the cylinder bank exposed, drove a two-blade wooden propeller of the tractor type, discharged its spent gases to starboard via a simple manifold, and was cooled by a frontal radiator with angled-back side elements.

Delivery and service
Deliveries of the D VII began in April 1918, and the first unit to receive the new fighter was Jagdgeschwader 1 commanded by Rittmeister Manfred Freiherr von Richthofen and comprising Jagdstaffeln 4, 6, 10 and 11. The fighter was then used to re-equip as many fighter units as possible including JG 2 (Jastas 12, 13, 15 and 19) and JG 3 (Jastas 2, 26, 27 and 36) as well as the independent Jastas 5, 7, 8, 14, 16, 17, 20, 22, 23, 24, 28, 29, 30, 32, 35, 37, 40, 44, 46, 47, 48, 49, 51, 52, 53, 54, 56, 57, 58, 59, 66, 69, 71, 74, 79 and 80.

From May 1918 the D VIIF became available as the variant of the D VII with the BMW IIIa engine, and this model offered performance so much improved over that of the basic D VII, especially in climb and performance at medium and high altitudes, that demand soon outstripped supply and the aircraft became the mounts mainly of the most experienced and successful pilots. Production of the D VII was still under way at the end of the war, when the German fighter squadrons had about 775 of the type in service out of the total of about 1,750 aircraft that had been delivered by Fokker (861 machines) and the two Albatros companies (at least the same number again). The type had also recently entered production for the Imperial Austro-Hungarian army air service at the MAG plant in Hungary, where some 50 aircraft were completed up to 1919 with the revised powerplant of one Austro-Daimler water-cooled six-cylinder inline engine rated at 210 hp (156.5 kW).

Further developments
Experimental and developmental variants of the D VII were numerous. The V.18 was produced at the same time as the two V.11 prototypes and had a long-chord fin with a curved leading edge. The V.21 was a development with tapered wing panels and was flown in the second ‘D’ category fighter competition of May and June 1918. The V.22 was the definitive pre-production prototype of the D VII with all the best features of the V.11, V.18 and V.21. The V.23 was a version of the V.22 with constant-chord wing panels. The V.24 was an experimental development of the D VII with the powerplant of one Benz Bz.IVü water-cooled six-cylinder inline engine rated at 240 hp (179 kW) and flown in the second ‘D’ category trials. The V.29 was an experimental parasol-wing development of the D VIIF for participation in the third ‘D’ category trials of October 1918. The V.31 was a D VII fitted with a hook to tow the V.30 glider using D VIII parasol-wing fighter components. The V.34 was a D VIIF with a revised tail unit. The V.36 was a development of the V.34, and of the two such aircraft the first had the same type of tail unit as the D VII and the second had a fuel tank in the spreader bar fairing and no cut-out in the upper-wing trailing edge. The V.38 was a two-seat development of the D VII for the reconnaissance fighter role and was placed in unofficial production as the C I that became the C.I after the war.

After the Armistice, Anthony Fokker managed to escape to his native Netherlands with large amounts of money as well as much matériel and many aircraft including components for some 150 examples of the D VII of which 148 were then assembled and sold to the USSR (50 aircraft) and the Netherlands (98 aircraft), for which the type served in the Netherlands army air service (72 machines), Netherlands navy air service (20 machines) and Netherlands East Indies army air service (six machines).

Fokker restarted production of the D VII in the Netherlands, and a limited number of aircraft from this source were sold to Denmark, Finland, Poland, Romania and Sweden. Although the Armistice agreement had specified that all D VII fighters were to be handed over to the Allies, many German squadrons destroyed their aircraft while a number of pilots flew their aircraft to neutral countries such as Denmark, the Netherlands, Sweden and Switzerland. Of the D VII fighters actually delivered to the Allies, numbers were handed over to Belgium, Italy and the USA. Within a total of 324 ex-German aircraft handed over to Belgium were 75 examples of the D VII, of which 35 were taken into Belgian service as fighters that later became advanced trainers in the later stages of their career into 1931. Italy used its aircraft only for trials purposes, some of them revised with a water-cooled six-cylinder inline powerplant of one BMW unit rated at 250 hp (186 kW) or one Siddeley Puma unit rated at 230 hp (171.5 kW). Some 142 D VII fighters were included in the total of 347 captured aircraft shipped to the USA, where a number entered limited service for operational or evaluation purposes. Switzerland bought 10 aircraft (eight D VII and two D VIIF fighters) from the Allied Control Commission after the war, and the Alfred Comte Flugzeugfabrik then built an additional eight aircraft.

Specification

Fokker D VII

Accommodation: pilot in the open cockpit

Fixed armament: Two 0.312 in (7.92 mm) LMG 08/15 fixed forward-firing machine guns with 500 rounds per gun on the upper part of the forward fuselage with synchronisation equipment to fire through the propeller disc

Powerplant: One Mercedes D.III liquid-cooled six-cylinder inline piston engine rated at 160 hp (119 kW) for take-off, or Mercedes D.IIIa liquid-cooled six-cylinder inline piston engine rated at 175 hp (130.5 kW), or BMW IIIa liquid-cooled six-cylinder inline piston engine rated at 185 hp (138 kW) for take-off and 160 hp (119 kW) for cruising

Fuel capacity: internal 20.9 Imp gal (25.1 US gal 95 litres) external none

Dimensions: span 29 ft 3.33 in (8.90 m) area 217.44 sq ft (20.20 m²) length 22 ft 9.67 in (6.95 m) height 9 ft 0 in (2.75 m) with the tail up

Weights: empty 1,508 lb (684 kg) normal take-off 1,874 lb (850 kg) maximum take-off 2,006 lb (910 kg)

Performance: maximum level speed 101 kt (116 mph 187 km/h) at 3,280 ft (1000 m) declining to 100 kt (116 mph 185 km/h) at sea level with the D.III engine, or 108 kt (124 mph 200 km/h) at 6,560 ft (2000 m) declining to 106 kt (122 mph 196 km/h) at sea level with the BMW IIIa engine climb to 6,560 ft (2000 m) in 8 minutes 0 seconds with the D.III engine or 5 minutes 15 seconds with the BMW IIIa engine service ceiling 19,605 ft (5975 m) with the D.III engine or 21,325 ft (6500 m) with the BMW IIIa engine endurance about 1 hour 20 minutes

Operators: Belgium (35), Denmark (not available), Finland (not available), Germany (c. 1,750), Hungary (50), Netherlands (98), Poland (not available), Romania (not available), Sweden (not available), Switzerland (18), USA (142) & USSR (50)


Fokker D.VII Reproduction

Most experts agree that the Fokker D.VII was the finest all-around fighter plane of World War I. Designed by Reinhold Platz, the prototype was test-flown in a January 1918 design competition by a number of notable German airmen, including Manfred von Richthofen. The D.VII was the clear winner, and was ordered into immediate production at Fokker, as well as under license at two Albatros factories. The different production lines worked from separate drawings, and their respective D.VII output and parts were not completely standardized. Regardless, by late April 1918, the first D.VIIs arrived to waiting combat units. By the end of the war in November, 775 were in service.

Pilots found that the Fokker had good visibility and was a maneuverable but relatively easy ship to fly. The D.VII remained very controllable even at its altitude ceiling, and pilots were able to make it "hang on its prop" to fire upward at higher-flying Allied machines. Famous German aces such as Ernst Udet, Erich Löwenhardt, and Hermann Göring achieved great success in the D.VII. Allied aviators began to dread the appearance of the "straight wings" with their "coffin noses." Although it couldn’t reverse the declining fortunes of the German Army on the ground in late 1918, the feared Fokker D.VII was the only airplane mentioned specifically by name to be handed over to the Allies under the Armistice terms.

Fokker D.VII armament consisted of two 7.92mm Maschinengewehr (MG) 08/15 machine guns, with interrupter gear to fire through the propeller arc. These guns were sometimes referred to as "Spandau," in reference to the arsenal where much of the German small arms development and production occurred.

The Museum's reproduction aircraft was started by the noted aircraft replica builder Joe DeFiore. After buying the basic steel-tube fuselage from DeFiore, Doug Champlin shipped it to Jim and Zona Appleby, who later completed the aircraft for museum display. Equipped with an original Mercedes water-cooled engine and two Spandau machine guns, it is authentically painted in the unique lozenge-pattern camouflage of the period and carries the winged-sword emblem of German ace Rudolf Berthold.

Most experts agree that the Fokker D.VII was the finest all-around fighter plane of World War I. Designed by Reinhold Platz, the prototype was test-flown in a January 1918 design competition by a number of notable German airmen, including Manfred von Richthofen. The D.VII was the clear winner, and was ordered into immediate production at Fokker, as well as under license at two Albatros factories. The different production lines worked from separate drawings, and their respective D.VII output and parts were not completely standardized. Regardless, by late April 1918, the first D.VIIs arrived to waiting combat units. By the end of the war in November, 775 were in service.

Pilots found that the Fokker had good visibility and was a maneuverable but relatively easy ship to fly. The D.VII remained very controllable even at its altitude ceiling, and pilots were able to make it "hang on its prop" to fire upward at higher-flying Allied machines. Famous German aces such as Ernst Udet, Erich Löwenhardt, and Hermann Göring achieved great success in the D.VII. Allied aviators began to dread the appearance of the "straight wings" with their "coffin noses." Although it couldn’t reverse the declining fortunes of the German Army on the ground in late 1918, the feared Fokker D.VII was the only airplane mentioned specifically by name to be handed over to the Allies under the Armistice terms.

Fokker D.VII armament consisted of two 7.92mm Maschinengewehr (MG) 08/15 machine guns, with interrupter gear to fire through the propeller arc. These guns were sometimes referred to as "Spandau," in reference to the arsenal where much of the German small arms development and production occurred.

The Museum's reproduction aircraft was started by the noted aircraft replica builder Joe DeFiore. After buying the basic steel-tube fuselage from DeFiore, Doug Champlin shipped it to Jim and Zona Appleby, who later completed the aircraft for museum display. Equipped with an original Mercedes water-cooled engine and two Spandau machine guns, it is authentically painted in the unique lozenge-pattern camouflage of the period and carries the winged-sword emblem of German ace Rudolf Berthold.