On december 30 1955, a Fokker F-VII-a landed on Schiphol. This aircraft is used as a museumaircraft and is still exposed in the Aviodome. Adriaan Viruly was also present at that day.

The Fokker F.VIIa was the first airliner in the world with a air-cooled sterlingengine.

This type of Fokkers joined KLM's fleet in 1925. It could seat 8 passengers but was also used as freighter carrying 900 kilograms of cargo.

This plane was larger than his predecessor, the F.VII.

A number of technical improvements had also been made, one of which undoubtedly received a warm welcome from passengers: the cabins were now heated in winter.

Although the F.VII was series-built to the extent of five aircraft, both KLM and Fokker regarded the machines as prototypes. The aircraft were frequently modified, different types of engines were installed and tested, various forms of tail fin were tried, and the complicated undercarriage was simplified. Numerous other changes were also made which were not visible from the outside. Plesman, who tended to be outspoken rather than tactful, was not too happy about these experiments. He wanted ready-made aircraft capable of producing profits.

In a snide reference to Fokker's wartime activities, he once wrote to Fokker that "KLM is not a 'Versuchsanstalt'" (German for test center).

In fact Plesman's engineers experimented just as much as Fokker's, and both companies at Schiphol were working towards the same goal: to produce the best possible aeroplane. During the 'twenties, aircraft gradually became more sophisticated and complex,

Fokker had meanwhile hired a number of university-trained engineers who proved to be very successful. Like most people, Fokker had his good points and his bad, and a little-publicished good point was his ability to select the right man for the job.

The first university-educated engineer to join Fokker was Ir. Jan Roosenschoon who started at the Veere plant on 1 May 1922. Second was Ir. Marius Beeling who, on 26 March 1923, was appointed assistant to Rethel in Amsterdam.

Both appointees had studied mechanical engineering at Delft University. They had then gone for a further year to study aeronautics, and so had become the first Dutchmen to attain a degree in aeronautical engineering. The Dutch National Institute for Aeronautical Studies (RSL), now the NLR, National Air & Space Laboratory, which was responsible for awarding certificates of airworthiness, felt that it also should offer an opening for an engineer of academic level. This led to the Institute hiring Ir. Bertus Grasé who was both a graduate engineer and a pilot.

As Fokker wanted to avoid difficulties with Grasé as an employee of the RSL, he hired him also simply by offering him a better salary. Fokker never regretted this as Grasé proved to be outstanding both as an engineer and as a pilot.

Fokker and his newly-hired staff were very conscious of the fact that the F.VII as designed by Rethel could be developed into something better.

Operational experience, numerous tests, modifications and trial installations had almost without exception, given good results. Everything confirmed that the basic design of the F.VII was wholly sound. And so without any contract from KLM or any other airline, Fokker ordered that the F.VII be redesigned as the F.VIIa. As Fokker himself was already very busy starting up his business in America, his own contribution was relatively small.

Now with a team of capable engineers, this was not too critical. It is not quite clear why the new model was designated F.VIIa and not F.VIII as would have been logical. Some historians believe it to be the result of superstition, seven being Fokker's lucky number. However as Fokker was not at all superstitious, this is a rather doubtful explanation.

A more likely possibility is that the F.VIIa did not differ from the F.VII sufficiently for a new number to be justified.

Manufacturing the inset ailerons was extremely simple. The wing, including the ailerons, was first built as a single unit. Then, after the wing had been covered with a plywood skin, the ailerons were simply sawn off. Following some rework of their leading edges, they were re-attached to the wing by hinges.

Redesign of the undercarriage was performed by Grasé. He replaced the complex F.VII arrangement with a simple main strut extending from each wheel directly up to the main spar. The struts were each braced by two streamlined tubes attached to the lower edge of the fuselage.

A number of rubber rings in the main strut absorbed the bulk of the shocks which unavoidably occurred

First flight of the F.VIIa was on 12 March 1925. It is assumed that Grasé was the pilot.

Powerplant was a 420 hp water-cooled Packard Liberty engine. It is not clear why an American engine was chosen. Neither is it known why a water-cooled unit was chosen at a time when the airlines much preferred air-cooled engines which avoided the weight of the coolant system and its many attendant failures.

The F.VIIa engine mounting however allowed for easy replacement with an alternative engine. For publicity purposes, the name 'FOKKER' was painted on the fuselage and wing in large letters. The letter 'H' for Holland was painted on either side of the rudder. Also for publicity purposes some record flights were attempted, not all of them successfully.

Six weeks after the maiden flight, on 30 April 1925, Grasé tried to better the world altitude record with a 1000 kg useful load.

He was only partly successful as he beat the existing record of 5,751 meters by a French Farman Goliath, by only 20 meters.

Undoubtedly, representatives from KLM were among the invited guests, but they did not need the demonstration to be convinced of the merits of the aircraft. They had already seen the F.VIIa on the drawing board and one month earlier, on 26 June 1925, KLM had ordered an aircraft at a price of 28,500 guilders.

The contract specified that the engine would be furnished by KLM, otherwise - as Plesman put it - Fokker will make a profit on the engine also. He was probably correct. After having flown for some time without a registration, the prototype F.VIIa was officially registered on 21 August 1925 as H-NACZ.

Shortly thereafter the aircraft, together with a three-engined version of the F.VIIa, was shipped to the United States. The plan was that both machines would take part in the Commercial Airplane Reliability Tour as organized by the Ford Motor company.

A total of 36 F.VIIa's was built by Fokker, and KLM built another four using spare parts supplied by Fokker plus used components from written-off aircraft. The full story of virtually all the 40 F.VIIa's is known.

KLM bought 11 F.VIIa's directly from Fokker. Most of them had uneventfull lives. A notable exception was the aircraft which American millionaire van Lear Black chartered from KLM.

One of the F.VIIa's built by KLM ended up with the National Institute for Aeronautical Studies

For the F.VIIa registered H-NADK, life became interesting after conclusion of its KLM career. In September 1927 this aircraft was sold to a Mr. McIntosh who baptised it 'Princess Xenia'. McIntosh had some ambitious plans and, prior to delivery he had the machine modified to undertake long distance flights.

On 16 September 1927, together with a Mr. Fitzmaurice, he took off from an airfield near Dublin for a transatlantic flight. After only a couple of hours flying, an exceptionally strong headwind forced them to return. Undeterred, McIntosh set himself a new target. On 15 November he departed on a London - Karachi return trip accompanied by the well-known Australian flyer Bert Hinkler, as co-pilot. They made Karachi, but on the way back had to make an emergency landing which extensively damaged the aircraft. A second attempt, which started 10 June 1928, also ended in failure. Third time lucky however.

Mr. Barnard, new owner of the aircraft, decided to attempt a return flight to Karachi.

With him as co-pilot was a Mr. Elliot, and the Duchess of Bedford as passenger.

As well as supplying F.VIIas to KLM, Fokker sold the type to a number of foreign airlines.

Seven F.VIIa's went to CIDNA in France, six to LOT in Poland, three to Balair in Switzerland, two to Malert (Magyar Légiforgalmi RT) in Hungary, two to Denmark for DDL which later bought a third (used) aircraft, and three to STAR in France.

Most of these aircraft served their airlines faithfully for many years during which time they underwent a series of modifications.

KLM's first F.VIIa was H-NACT.

After having performed its monotonous duty with the airline for many years, it came to an inglorious end when it was hit by a bomb at Schiphol in May 1940 at the time the Germans invaded Holland.

In the Dutch National Aviation Museum 'Aviodome' at Lelystad however, there is still an F.VIIa with H-NACT as its registration.

The aircraft is not the original KLM F.VIIa and never flew for the airline.