Kingdom of Hungary (1944)
Fictitious Jet Attacker / Dive Bomber – 1 Scale Model Built

The Manfréd-Weiss XNI-02 Kaméleon (Chameleon) is a fictitious Second World War Hungarian jet-powered attacker aircraft written about in the April 1980 edition of the Hungarian aviation magazine Repülés (Flight) as an April Fools joke. The brainchild of Hungarian author György Punka, the XNI-02, though meant as a harmless April Fools joke, unfortunately fooled unsuspecting readers and caused controversy within the military aviation fanbase. As a result, numerous websites, magazine authors, armchair historians and casual readers are still convinced to this day that the XNI-02 Kaméleon was an authentic project undertaken during the war and believes it existed.

Alleged History

According to the April 1980 edition of the Hungarian aviation magazine “Repülés”, while working for the Hungarian Manfréd Weiss Steel and Metal Works, (Weiss Manfréd Acél- és Fémművek, also known as “Csepel Works”) engineer Pál Nemisch designed a jet attacker aircraft in 1944. Due to the frequent Allied bombing and Hungary’s shortage of supplies, Nemisch presumably decided to base his design off pre existing components taken from other aircraft. Christened the “XNI-02”, the aircraft gained the nickname of Kaméleon (Chameleon) due to the number of parts incorporated from foreign designs. The XNI-02’s construction consists of a concoction of German, American and indigenously manufactured parts. Further details of the XNI-02’s design process are unknown, as Punka did not expand on them.

Construction of the XNI-02 is presented as having began in mid to late 1944, after parts for the aircraft were collected. The prototype began assembly in Kőbánya, Hungary, but construction was relocated to an underground aircraft production facility near Augsburg, Germany. This can possibly be accredited to Operation Margarethe, the German occupation of Hungary to ensure their loyalty to the Axis. The XNI-02’s development team would once again be relocated to Austria, near Wiener Neustadt prior to November. The XNI-02 prototype was presumably completed by the Wiener Neustädter Flugzeugwerke factory and made its maiden flight on November 6th.

On April 1st of 1945, Lieutenant R. Taylor from the USAAF 385th Fighter Group was patrolling Austrian airspace in search of Axis fighters with his North American P-51 Mustang. While flying near the town of Linz, he spotted a rather peculiar looking aircraft flying to his starboard side at an altitude of approximately 9,840 ft / 3,000 m. While trying to get behind the mysterious fighter, Lt. Taylor inadvertently revealed his presence to the aircraft which led to it speed away. Determined to chase down this mysterious aircraft, Lt. Taylor proceeded with the chase. For some odd reason, the aircraft Lt. Taylor was chasing began to slow down and extended its landing gears. Now in a position to engage the aircraft, Lt. Taylor fired towards the unidentified aircraft. Failing to shoot it down in the initial pass, Lt. Taylor pulled off and reengaged it. This time, the burst of gunfire from his Mustang seemingly crippled the unidentified aircraft and thus forced the pilot to bail out. The aircraft crashed shortly thereafter. After returning to the 385th Fighter Group’s homebase in Foggia, Italy, the guncam on Lt. Taylor’s Mustang was examined and the film revealed that the mysterious aircraft Taylor shot down was the sole XNI-02 (the guncam still frame in the magazine was created using Punka’s model). This, however, was unknown to them at the time. This information would be revealed later on from an unnamed technician who provided pictures and some information regarding the XNI-02 after the war. On that day, the XNI-02 was supposed to be performing a weapon firing flight test, but this would never occur as Lt. Taylor was able to successfully shoot down the prototype. In Lt. Taylor’s private log book, he recorded the victory as: “Unidentified jet over Linz. 10:35, 1945 April 1st”. The reasons why the XNI-02 test pilot decided to slow down and extend his landing gear are up for personal interpretation, as the story is fictitious in itself. The test pilot may have believed he lost Lt. Taylor and decided to prepare for landing, or this was an indication that the XNI-02 was experiencing mechanical problems and needed to perform an emergency landing. Realistically though, the story was written in this way to cover up Punka’s XNI-02 model’s inability to retract its landing gears. It is unknown whether or not the radioman was present onboard the aircraft at the time of its shootdown.

The Wiener Neustädter Flugzeugwerke factory was also in the process of building the reconnaissance variant of the XNI-02 in 1945. The incomplete fuselage of this variant was destroyed by advancing Soviet troops when they overran the factory. Other than the attacker / dive bomber and reconnaissance variant, there was also plans to produce a night fighter and trainer variant for the XNI-02. These plans, however, were never acted upon due to the advancing Allied troops. Details of these variants are unknown as Punka did not write about them.

Supposed Design

As mentioned before, the XNI-02 Kaméleon is a fictitious jet fighter created by Hungarian author György Punka. All known photos of the XNI-02 are sourced from a model Punka created. Using components from several model kits, Punka was able to create a fairly realistic and convincing model. The XNI-02 model uses a North American P-51B Mustang’s fuselage, a set of the iconic gull wings from the Junkers Ju 87 Stuka (the model also uses the Ju 87’s horizontal stabilizer as an anhedral outer section of the regular wings), the Lockheed P-38 Lightning’s nose, and the BMW 003’s two engine cowls were taken from a Sud Aviation Caravelle passenger jet model. The combination of parts used for this aircraft is attributed to the fact that Hungary was unable to manufacture its own aircraft components. However, parts of the tail and nose were constructed using plastic and wood. In the original article written by Punka, only Stuka parts were mentioned. This could mean that the P-51 fuselage was either taken from captured models or the Hungarians reverse engineered it and indigenously produced them with modifications. The fuselage would have been reinforced with steel plates for protection, though every other part of the aircraft was constructed using wood and plastic.

The XNI-02 would have had space for two crew members, a pilot in the plexiglass cabin and a gunner / radio operator which would be housed in the nose (likely in a prone position). The gunner would be able to remotely control two 12.7x81mm Gebauer GKM 1940.M machine guns located under the nose help from a monitor. (The machine guns are not believed to have been installed on the prototypes.)

The XNI-02 was powered by two BMW 003 turbojet engines given to the Hungarians by the Germans. They are mounted on the rear fuselage on either side accompanied by a slight bulge in the fuselage which would have held the fuel tanks. It would appear that the fuel weight impacted the performance of the XNI-02 but guaranteed an increase in endurance and distance. The exact variant of the engines is unknown. The armaments consisted of two 30x184mm Rheinmetall-Borsig MK 103 autocannons and two remote-controlled 12.7x81mm Gebauer GKM 1940.M machine guns. The MK 103 cannons were mounted in the nose while two Gebauer GKM 1940.M machine guns were envisioned to be mounted under the nose. As an attacker, the XNI-02 prototype theoretically would have been able to mount two 550 lb / 250 kg bombs or four 8.26 in / 21 cm Werfer-Granate 21 rockets under the fuselage or wings.

The production variant of the XNI-02 would have had ejection seats for both crewmen, but this feature was not installed on the prototype. Curiously enough, the original prototype concept would have had a propeller-driven engine, but due to time constraints this experimental concept was not tested and jet engines were mounted right away.

Conclusion

Though the XNI-02 Kaméleon is a fictitious aircraft, the design of it would have been quite modern and advanced, but also unusual and with plenty of quirks that signal it as a fake design. The monitor assisted remote gunner system is an example of this. Though Punka was able to sell a convincing story of the XNI-02 Kaméleon, there are some questionable details which impact the veracity. For one, the fact that the Hungarians would have received BMW 003 turbojet engines in 1944 is quite unrealistic. At that time, German would have likely reserved their resources for use against the Allied forces. The basis of the design, although creative, would have imposed an issue for production facilities. The basis of the design resides on the availability of spare parts from existing aircraft, and if such parts were not available, the XNI-02 would have needed extensive modification to accommodate different parts.

Despite these flaws, Punka’s creation most certainly made an interesting and, to some degree, convincing story which made a great April Fools article. However, not everyone realized that this was, in fact, an April Fools joke and some took this as a real aircraft. This caused many other magazines and websites to write their own articles on the XNI-02, stating that it was a real project. The XNI-02 was even able to convince some Hungarian veterans, which led them to contact each other to see if anyone knew if this was a real project.

Variants

• XNI-02 Attacker / Dive Bomber – Attacker variant powered by two BMW 003 turbojet engines. One prototype was built and was destroyed on April 1st of 1945 when Lieutenant R. Taylor of the 385th Fighter Group shot it down during a test flight.
• XNI-02 Reconnaissance – Reconnaissance variant of the XNI-02. One incomplete prototype was in construction presumably at the Wiener Neustädter Flugzeugwerke factory in Austria. The prototype was destroyed by the Soviet troops.
• XNI-02 Night Fighter – Intended night fighter variant. Details unknown.
• XNI-02 Trainer – Intended trainer variant. Details unknown.
• XNI-02 Night Bomber – Intended night bomber variant. An IR (Infrared Radiation) bombsight would have been installed in the nose for use by the radio operator / gunner (bombardier in this context).

Operators

• Kingdom of Hungary – The XNI-02 Kaméleon was intended for use by the Royal Hungarian Air Force.

Gallery

Credits

• Punka, G. (1980, April). XNI-02 “Kaméleon”. Repülés, 17-18.
• Illustrations by Haryo Panji https://www.deviantart.com/haryopanji
• Edited by Stan L. & Carbon