Mini Pfeil; The Fokker D.XXIII

barely had the wright brothers proven that flight for heavier than air vehicles was possible then designers began to think on how to improve aircraft performance and the most logical way to accomplish that was more power either with engines offering greater horsepower or just fitting more engines of course more engines also meant more drag as multi-engine layouts increased an aircraft's wingspan to accommodate them which led to another idea the puller pusher layout with this an aircraft minimized the aerodynamic drag of utilizing multiple engines by fitting them in line with each other one acting as a tractor motor pulling the aircraft the other pushing it because of the theoretical advantages of this layout most designers and aero companies did at least experiment with the concept and one of these was anthony fokker who in 1915 built the k1 a three-seat aircraft that seated the pilot in a nacelle in the center of the aircraft with an engine both in front and behind him like most others fokker found that the puller pusher configuration required a lot more development to get correct and he abandoned the idea for more conventional designs though several aircraft of this configuration did ultimately get built and see both military and civilian service the complications in getting the aerodynamics correct meant that the concept was largely abandoned by most and polar pusher aircraft primarily became the trademark of the dornier company who built several models of flying boats using the principle but evidently anthony fokker also never completely wrote off the idea of building a puller pusher and not just a stately flying boat but as a high performance fighter skip ahead to the mid-1930s and the dutch authorities realized that the security situation in europe was looking rather worrisome and that they should probably take steps to shore up the defenses of the netherlands and one of the critical weak spots was the dutch air force up until that point this had just been a single fighter squadron which used fokker d-17 biplanes in 1937 a four-year plan was announced that would see the establishment of eight fighter squadrons two of which should be high performance interceptors the problem was the dutch aero industry didn't produce such an aircraft the best indigenous fighter available was the fokker d-21 which had been designed as a rugged colonial fighter though a solid aircraft and one which would do surprisingly well in the coming war it was inferior to modern aircraft then taken to the skies as a result the dutch would give serious consideration to buying hawker hurricanes supermarine spitfires and the heinkel he 112 to meet this requirement naturally the dutch-based fokker company weren't too thrilled on this plan the netherlands had traditionally followed a policy of buying homegrown aircraft up until that point which had suited fokker perfectly but with the threat of losing that monopoly fockers needed to up their game so they set about designing a new aircraft they would not only match their foreign rivals but would re-establish fokker as one of the premier fighter aircraft companies in the world to achieve that they needed an aircraft that was technically well in advance of the competition and so was created the fokker d23 this utilized a polar pusher layout by having two water sagitta isr air cooled inline engines one located in front of the single seat cockpit one behind which each produced 535 horsepower the d23 had a twin boom configuration was of all metal construction and also had a tricycle landing gear there are some discrepancies on the proposed armament and as it was never ultimately fitted it is likely that the question was never resolved but it seems that it was either to be six 7.92 millimeter fn browning machine guns or else seven point nine twos and two thirteen point two millimeter fn browning heavy machine guns which would have been fitted in the root of each boom the prototype was publicly displayed for the first time at the paris air salon in 1938 before it had even flown where it was naturally subject to much interest on may 30th 1939 the aircraft flew for the first time obviously for an aircraft that incorporated so many new ideas there were problems the rear engine was found to overheat largely because of airflow problems as the turbulence created by the front propeller disrupted the cooling airflow over the rear nacelle there were also concerns about how the pilot was expected to bail out in the event of a problem as he would most likely be hit by the rear propeller if he did so this led to proposals for the fitting of an ejection seat another advanced concept that was just in preliminary exploration at the time naturally all this meant that development was a gradual process and the d23 was to be subject to several alterations principally to the rear engine paneling and cowling to try to resolve the heating issue in total the prototype made 11 flights and though it seems to be unconfirmed it is reported that top speed was 326 miles per hour 525 kilometers per hour this wasn't bad though any service aircraft would have been much slower once equipped with armament and military fittings however the prototype was intended to be more of a proof of concept and any production aircraft was expected to have substantially more powerful engines fokker proposed that production aircraft could have either the yonkers yumo 210 or the rolls-royce kestrel engines both of which produced around 750 horsepower these engines were of a previous generation to the merlin and db600 series engines that both the germans and british were equipping their then current fighters with as a result fokker didn't anticipate issues acquiring either of these engines from their producers as they weren't considered critical for their respective countries own defense plans additionally these engines were considerably cheaper than the later models and costs were a major issue for the dutch defense ministry despite these lower powered engines the d23 configuration meant that top speeds for production aircraft equipped with them was anticipated to be around 350 miles per hour 563 kilometers per hour these speeds if accurate would have put the aircraft in the same league as the spitfire and the measuresmith bf-109 models then flying additionally focker was thinking actively about the possibility of using even more powerful engines should rolls-royce merlin's or db-601s be available for purchase or licensed production and be fitted to the d23 then top speeds were projected to be over 380 miles or 612 kilometers per hour in fact that almost certainly would never have occurred the outbreak of the second world war in september 1939 meant that no european nation was willing to supply engines as they were all desperately trying to build as many aircraft for their own needs as they could despite this the dutch still needed their interceptor and having left it too late now to acquire foreign aircraft they continued to run tests with the d23 until april 1940 when the undercarriage suffered damage during a test this meant that when the german invasion of the low countries occurred a few weeks later the fokker d23 was sitting in a hangar it was reportedly badly damaged in the fighting and subsequently vanished into history a fascinating aviation what if

Channel: Ed Nash's Military Matters

Views: 125,914

Keywords: Fokker, fighters, D.XXIII, puller-pusher, WW2, 2nd world war, forgotten aircraft, Dutch Air Force, Hawker Hurricanes, Supermarine Spitfires, Heinkel He112, Walter-Sagitta

Id: vBr6WV5MTN0

Length: 8min 21sec (501 seconds)

Published: Wed Feb 02 2022