Question: How long was Germany forbidden to manufacture or import aircraft?
About the article "Treaty of Versailles", section "Military restrictions".

Candidate passages:
The treaty was comprehensive and complex in the restrictions imposed upon the post-war German armed forces (Reichswehr).
The provisions were intended to make the incapable of offensive action and to encourage international disarmament.
Germany was to demobilize sufficient soldiers by 31 March 1920, to leave an army of no more than in a maximum of seven infantry and three cavalry divisions.
The treaty laid down the organisation of the divisions and support units, and the General Staff was to be dissolved.
Military schools for officer training were limited to three, one school per arm and conscription was to abolished.
Private soldiers and Non-commissioned officers were to be retained for at least twelve years and officers for a minimum of with former officers being forbidden to attend military exercises.
To prevent Germany from building up a large cadre of trained men, the number of men allowed to leave early was limited.
The number of civilian staff supporting the army was reduced and the police force reduced to its pre-war size, with increases limited to population increases; paramilitary forces were forbidden.
The Rhineland was to be demilitarized, all fortifications in the Rhineland and east of the river were to be demolished and new construction was forbidden.
Military structures and fortifications on the islands of Heligoland and Düne were to be destroyed.
Germany was prohibited from the arms trade, limits were imposed on the type and quantity of weapons and prohibited from the manufacture or stockpile of chemical weapons, armored cars, tanks and military aircraft.
The German navy was allowed six pre-dreadnought battleships and was limited to a maximum of six light cruisers (not exceeding ), twelve destroyers (not exceeding ) and twelve torpedo boats (not exceeding ) and was forbidden submarines.
The manpower of the navy was not to exceed including manning for the fleet, coast defences, signal stations, administration, other land services, officers and men of all grades and corps.
The number of officers and warrant officers was not allowed to exceed Germany surrendered eight battleships, eight light cruisers, forty-two destroyers, and fifty torpedo boats for decommissioning.
Thirty-two auxiliary ships were to be disarmed and converted to merchant use.
Article 198 prohibited Germany from having an air force, including naval air forces, and required Germany to hand over all aerial related materials.
In conjunction, Germany was forbidden to manufacture or import aircraft or related material for a period of six months following the signing of the treaty.
The Lympne events had their origin in the post-World War I state of aviation in Britain and in Germany.
Military aircraft production stopped immediately the war ended.
In Britain there were large stocks of surplus aircraft available at low prices, making it hard for manufacturers to develop new models.
Airlines were only slowly emerging, largely using converted military aeroplanes and having not found a certain economic model.
The old fighters, though effective for barnstorming were not economical or practical enough for the private owner.
In Germany the manufacture of powered aircraft was forbidden under the terms of the Treaty of Versailles, but glider development was allowed.
In 1921 a glider competitions was held in the Rhön mountains, and in mid-August 1922 the another was held at the Wasserkuppe.
The 1922 prize of 100,000 marks was won by a flight of 66 minutes, demonstrating the possibilities of engineless flight.
In response, the "Daily Mail" offered a prize of £1,000 to the pilot making the longest flight in England.
The Royal Aero Club chose Itford Hill on the South Downs just east of Brighton as a venue and the event was arranged for 16–21 October 1922.
This gave contestants just six weeks to design and build their gliders, or to bring them from Europe.
Thirteen gliders competed with each other and the autumn weather.
The best flight by an Englishman was that made by Fred Raynham in a Handasyde aircraft, lasting 113 minutes, but the Frenchman Alexis Maneyrol did better in his Peyret tandem monoplane, staying up for a world record 201 minutes to win the prize.
Given this demonstration of long duration unpowered flight it is not surprising that people began to consider the possibilities of glider-like aircraft, fitted with small engines, as sports aircraft for the private flyer.
The first Lympne meeting the following year and its slightly earlier counterpart in Vauville near Cherbourg, France were the result both of these ideas and a desire to build an aircraft which would satisfy the needs of private fliers and foster private aviation.
Unfortunately, in the opinion of many, both at the time and later, the restrictions imposed resulted in aircraft that had too-small engines, wheels that were too thin and of small diameter and engines which, though under powered, were too heavy relative to the often fragile, light-weight frames in which they were housed.
C. G. Grey, editor of 'The Aeroplane' at the time devoted two issues to "a four-page long diatribe" to the failures of the 1924 event and the author of 'The Lympne Trials' speaks of "a clear failure to understand what a private pilot or a flying club might need as a training aeroplane".
Nevertheless the trials did serve to stimulate public and industry interest in private aviation after the first world war and certainly exercised the ingenuity of designers to the maximum in complying with the restrictions placed upon them. 
With Germany forbidden from manufacturing aircraft by the Allies, Heinkel used his company's facilities to build private transportation.
In 1953 Heinkel began production of the Tourist scooter, followed by the Perle moped in 1954.
In 1956 he introduced the Heinkel Kabine bubble car.
Bubble car and moped production ceased shortly after the restriction on aircraft manufacture was lifted, but scooter production continued until 1965.
In 1959, Heinkel's company was sued by Edmund Bartl for being enriched by slave labor during World War II, however, the German Supreme Court dismissed his claims for filing too late and ordered Bartl to pay court costs and attorney's fees. 
Whilst Germany was prohibited from military aircraft manufacture by the Treaty of Versailles, Gotha returned to its railway endeavours, but returned to aviation with the rise of the Nazi government and the abandonment of the Treaty's restrictions. 
"EKW" (Eidgenoessische Konstruktionswerkstaette English: "Swiss Federal Constructions Works",also known as Eigenössische Flugzeug Werke - EFW, or as Flug + Werk).
The Federal construction workshops (ekw) was a composite of Swiss state-owned enterprises, with the aim to make the Swiss defense of imported arms independently.
It was established 1867 in Thun.
Already around 1915 Switzerland put in an effort to make themselves independent of the import of military aircraft.
Long-standing connections to the ETH Zurich ensured the necessary know-how.
After the EKW C-3604 the production of aircraft at EKW Thund was set to an end.
But EKW was still building Tanks for the Swiss Army, own tanks but also licence production of M113 and Leopard 2 tanks.
Since 1995 it is part of RUAG Defence.