Knoller C.II – Old Unreliable

Knoller C.II preserved in the National Technical Museum in Prague, Czech Republic in 2019.

Wings for an Empire 

In 1914, the air arm of the Austro-Hungarian military was in a less than optimal state of readiness and in desperate need of modern aircraft to effectively fight in the aerial battlefields of the First World War.

The Austro-Hungarian military faced a perplexing procurement issue at the time as the entire aviation industry of the empire was under a monopoly held by two men: Ludwig Lohner (1858 – 1925) and Camilio Castiglioni (1879 – 1957). Theirs was a monopoly that was well in place before the outbreak of the war.

Not wishing to be subject to the limitations and compromises that dealing with a monopoly could bring, the military encouraged other aircraft companies to establish themselves in the Austro-Hungarian Empire. While that did work to create a great deal more choice in who the military could deal with, it created the opposite problem to a monopoly: too much choice and too many companies creating too many machines and using too many resources in the process.

To counter this issue, the Knoller Program was created in 1915. Named for Professor Richard Knoller (1869 – 1926), a highly regarded engineer at the Vienna University of Technology who the military already had a good working relationship with, the progam was intended to entrust the design of a new aircraft to Knoller and then have the aircraft built under contract by different companies.

Knoller C.II preserved in the National Technical Museum in Prague, Czech Republic in 2019.

Haste Makes Waste

The Knoller Program lasted from 1915 to 1917 and had the primary purpose of creating powerful two seat aircraft that could fill a number of purposes. To this end, the program resulted in three aircraft types, the C.II being the final of them, all of which were failures and seen as unfit for military service.

The failure of the aircraft was not due to any incompetence on the part of Richard Knoller himself, but to the ridiculously short deadlines he was given to work within. He simply was not given the time to bring any of the designs in the program to maturation in the timeframes he was provided with.

The first aircraft of the Knoller Program was the B.I. Designed in January of 1915, but not completed until November of that year, the B.I suffered a number of delays and was found to be a very dangerous aircraft to fly due to structural weaknesses and poor handling qualities.

The B.I was followed by the C.I. Like the B.I before it, the C.I was beset with a variety of developmental delays before it took to the air for the first time. Also like the B.I, the C.I had a number of structural and handling shortcomings that made it unfit for service.

The third and final aircraft of the Knoller Program was the C.II, which first flew in 1916. Like the two designs before it, the C.II was structurally unsound, poorly built and unpleasant to fly.

The Knoller Program was brought to an end by parliamentary decision in 1917. Parliament had reconvened for the first time since 1915 and once it had been brought to their attention how much money and resources the military had put into the program with so little to show for it, all funding for the program was ordered to be stopped and the program terminated.

That order, however, did not come before the military had ordered a total of 185 Knoller aircraft and a C.II was involved in a fatal crash after its wings collapsed in flight. The military ended up with nearly 200 useless aircraft from the program, most of those aircraft were put into storage in incomplete states of construction and never flew at all. According to some sources, some of those aircraft did see service as ground maintenance trainers.

The Knoller Program was  ultimately a tremendous waste of money that got in the way of the Austro-Hungarian military’s goal of modernizing its air arm rather than serving it. Companies that could have been building superior aircraft designs were often stuck wasting their time building Knoller designs.

Knoller C.II preserved in the National Technical Museum in Prague, Czech Republic in 2019.

The Knoller C.II Itself

The C.II was a fairly typical biplane design for its time. The wings were fabric covered and the upper wings slightly swept. The fuselage was fully wood construction.

The aircraft was designed primarily for observation work and had a crew of two. The observer station had a mount for a defensive machine gun and there was also a bomb rack on the fuselage with space for three bombs.

Around 75 examples of the C.II were built between three companies: Aviatik, Lohner and WKF.

All versions of the C.II were powered by Daimler six cylinder liquid cooled engines of either 160 or 185 horsepower.

Knoller C.II preserved in the National Technical Museum in Prague, Czech Republic in 2014.

What Remains and Learning More 

Given the abject failure and wastage all three Knoller aircraft types from the progam represented, and the unpopularity they experienced by those unfortunate enough to be tasked with flying them, it’s rather surprizing that a single example of any of them still exists today.

While there certainly isn’t any nostalgia behind the C.II that might lead someone to make a full scale flying replica of one any time soon, there is one genuine C.II left in the world to see. The National Technical Museum in Prague, Czech Republic has a Lohner built example of the C.II on display in their transport hall display.

The following links will take you to articles about aviation in Austria-Hungary, the Knoller Program and the C.II in general:

Aviation in Austria-Hungary in WWI
The Knoller Program
Knoller Program Aircraft
National Technical Museum’s Knoller C.II