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Type F.V.
Type of aircraft
Passengerplane
Country Netherlands
Date first flight 1922
Crew 2
number of passengers 8
Enginetype Rolls-Royce Eagle
Engine
power
360 hp

Dutch East Indies

 

On 1 May 1922 the F.V was entered in Fokker's name in the Dutch register of aircraft.

A year later in March 1923, the Comité Vliegtocht Nederland-Indië - the Netherlands-Indies Flying Expedition Committee - became interested in the F.V. The committee wanted to work towards achieving the first flight to the Dutch East Indies colony, now known as Indonesia. Such a flight would open the way for a future scheduled service to the Indies to be operated by KLM.

The journey time by aircraft would be considerably less than by ship. Plesman wanted to use Fokker aircraft for this, and Anthony Fokker of course agreed wholeheartedly.

To stimulate the pioneering spirit the Dutch East Indies government, as early as October 1919, had put up 10,000 Dutch guilders as prize money for whoever would complete such a flight within 14 days. The Indies' government was not very knowledgeable about flying or they would have realized that this was an inadequate sum and that to fly to the Indies within 14 days was technically impossible at that time.

After an article in the magazine 'De Auto' entitled "Amsterdam - Batavia by airplane" had explained these problems, the prize money was raised to 50,000 guilders and the permitted travel time to one month. This aroused interest especially in military circles.

Numerous plans were made, but they were always thwarted by the lack of a suitable aircraft. It had even been announced that if the necessary money was made available, the flight to the Indies would take place with the F.V in October 1923. No such flight took place and in any case Fokker, who was a member of the Comité, had to admit that the aircraft was not suitable for this enormous journey.

Fokker F.V

Fokker F.V

Fokker F.V as a doubledecker

Fokker F.V, cabin for 8 passengers

Fokker F5: caine chairs in the cabin

The F.V under test by Deruluft, being refeulled at Smolensk

Monoplane and Biplane


An aircraft that can fly as a monoplane or as a biplane: that has not happened very often in aviation history.

The Fokker F.V was just such a remarkable aircraft. The lower wing was designed so that it could be fitted - or omitted. In this way the F.V was a very original concept, but it was not a success and only one aircraft was built. It is not clear what inspired the design and construction of the F.V.

Little or no correspondence remains which might provide a clue, not even a letter from KLM to Fokker raising the matter of a larger aircraft than the F.III.
It is certain that Reinhold Platz was the designer.

It is assumed that Anthony Fokker started the F.V on his own initiative to meet an expected demand for larger commercial aircraft.

He also toyed with the idea that the first flight to the Netherlands Indies could be made with this machine.

 

With only a brief instruction as to the detailed design, the chief designer got to work in the summer of 1922. Fokker was about to leave for America and had little time to discuss the design. Platz had to work it out on his own in Veere.


Innovations


It is clear from the appearance of the F.V that its design gave Platz a lot of difficulty. No wonder, as quite a few innovative features had to be introduced.

The F.V differed in a variety of ways from what was usual with Fokker. Most remarkable as already mentioned, was that the aircraft allowed the choice between taking to the air as a monoplane or as a biplane. The lower wing was removable, and was connected to the upper wing simply by 'N' struts.

There were no bracing wires, so the mounting and demounting could be done quite quickly. The philosophy behind the removable lower wing was that the user had a choice between a limited useful load together with a high speed as a monoplane, or a heavier load and a lower speed as a biplane.

The higher speed as a monoplane derived from the reduced drag when the lower wing was omitted. The larger wing area of the biplane permitted a heavier load. In practice the lower wing resulted in only a limited benefit. Part of the lift on the lower wing was in fact transmitted to the upper wing via the 'N' struts, so they still had to carry the entire load of the aircraft.

According to observers, the F.V flew most of the time in biplane configuration and only occasionally as a monoplane. Another peculiarity of the F.V was its different fuselage construction.Platz broke with the Fokker tradition of a tubular steel frame covered by fabric. In the area of the cabin, he fitted inner and outer skins of 1.5 mmthick plywood to the tubular frame. The 3-ply was both nailed and glued, and because nailing to steel tube was difficult, the 3-ply was first glued to wood.

 

Fokker F5 engine mounting

This construction added useful extra strength where, in a machine the large size of the F.V, some of the tubular members were quite lengthy and could be in danger of buckling. Platz had studied the buckling theory of the Swiss mathematician Euler, but it is doubtful if he understood it. In those days, that was how it was in the aviation industry.

In any case, the result appeared to be strong enough - as can be read in a 1922 report on the loading of an F.V cabin test piece. The unusual fuselage construction was intensively tested by the RSL, the Dutch national aeronautical laboratory - where the maintenance aspects received particular attention. They researched, for example, how the plywood-covered areas of the tubular steel frame could be checked for cracks or deformation.

This was obviously difficult as it required a lot of dismantling of the structure to permit the inspection to be made every 50 hours. The research gave the RSL a valuable insight into the requirements that were needed to facilitate aircraft maintenance. In the end, the double-skinned cabin wall was not a success.

In flight, the plywood sheets vibrated so heavily that the passengers were unable to hear one another talking.


Cabin


The cabin of the F.V provided generous space for eight passengers.

With a ceiling height of 5 ft 11 in, most of the passengers could even stand upright. The aircraft was fitted with a larger door than either the F.II or the F.III and it was not necessary to bend so far. The F.V was further equipped with an effective heater. An interesting innovation was a toilet, and there was even provision for passengers to wash or take a drink of water.

The toilet was not really a luxury as the F.V was intended to make longer-duration flights. For this reason also the aircraft was equipped with a two-man cockpit with dual controls so that the pilots could alternate during the flight.

The F.V's engine gave the aircraft a maximum speed of 119 mph in monoplane form.

 

Because a two-bladed propeller would have too big a diameter, Platz wanted to equip the aircraft with a four-bladed airscrew. This was also preferable to help reduce the propeller noise. Because such propellers were hardly available then, Platz decided to mount two two-bladed propellers in front of each other.

Finally, to protect the passengers as far as possible against engine noise, the exhaust pipes were led rearwards above the cabin windows. By tapping-off warm air from around the exhaust pipes, the cabin could be heated. This was a real novelty at a time when a warm-water heater was the order of the day and airlines even provided passengers with fur-lined leather coats against the cold. But even these advanced features did not help the F.V to become a success.


First flight


The F.V was built at Veere but, with no airfield there, the aircraft could not be flown. Normally, completed aircraft were first taken to the nearby military airfield at Souburg. However this did not always suit the military authorities, as was the case with the F.V. Because the factory at Veere was next to water, it was decided to transport the F.V to Schiphol by ship.

There, test pilot Herman Hess made the first flight on 7 December 1922. Directly after, Fokker himself flew the aircraft with Hess as co-pilot and, among others, the aviation journalist Henri Hegener as passenger. Fokker was far from being enthusiastic about the performance of the F.V.

 

He did not even give instructions for improvements as he had always done after test flights in earlier machines.

The F.V did however get a vertical stabilizer to improve directional stability, but for the rest the aircraft was left as it was. Fokker was not the only sceptic. The view of Henri Hegener, the aviation Journalist, was far from one of praise. Hegener was a good friend of Anthony Fokker and got to know the F.V from his own experience with the aircraft. He thought the noise in the cabin was deafening and he also noted the heavy vibration. Later Hegener even wrote that the excessive vibration prevented sharp photographs of the F.V in the air from being taken.


Deleted


In view of the experiences with the F.V, it was no wonder that little enthusiasm was shown by the airlines.

The F.V was tested for two weeks by Deruluft but they showed no further interest. In the end, Fokker salesman Friedrich Seekatz succeeded in finding a customer for the one and only F.V: ÖLAG in Austria.

In May 1926 the F.V was therefore deleted from the Dutch aircraft register with the note: "Sold to Austria".

 

Today, Austria's airworthiness authority no longer has any details of this purchase, nor about the use of the F.V. Even aviation historians are groping in the dark with this machine.

In publications, a company named Pojatzi is referred to as the next owner of the F.V, and later a certain Heinrich Schalek. These details can no longer be verified however and that also goes for a rumour that the aircraft finally end.