The sky is the limit

SR-71 Blackbird aircraft, including also the A-12 and M-21. The D-21 drone is also accepted tothis challenge.

Antonov An-2

Boeing B-17s

Grumman F-14 Tomcat

de Havilland Canada DHC-3 Otter

Concorde

F-85

MiG-29 and its derivatives.

All the versions of the world’s first commercial airliner, de Havilland Comet, including also her military derivatives as the Hawker Siddeley Nimrod.

F-4 Phantom

Boeing 747

Messerchmidt Bf-109 and any of its derivatives or replicas

Lockheed C-130 Hercules

Spitfire or any other derivatives or replicas.

Boeing 707 or any of her derivatives, civilian or military. The prototype Boeing 367-80 is also allowed.

P-51 Mustang aircraft and artifacts.

Douglas DC-3 aircraft, including the military versions or aircraft built under licence, as Li-2 and so on.

Lockheed Constellation pictures, art, artifacts. All versions are allowed, including the military ones.

Hawker Hurricane pictures - aircraft, models, artifacts, patches and so on.

Bush airplanes and pilots

Royal Air Force aircraft, people, artifacts.

Aircraft belonging to the Navy, operational or not.

Militaryaircraft bearing the red star markings. Could be Russia, Chinese, North Korean, Yougoslav and so on.

Upload your best aviation picture. It could be an aircraft, aircrew, airport or anything else related toaviation.

New Year party pictures.

Traditional Christmas celebration: home and street decorations, Christmas trees, dinner, churcch gatherings, Christmas party and so on.

Christmas decorated tree.

Sea planes or amphibious aircraft.

Aircraft designed for firefighting or adapted for firefighting air operations using drop containers, buckets and so on. On the aircraft adapted for firefighting, the special equipment must be visible or the picture must capture the aircraft during the fire extiguishing operation.

Chinese built aircraft, including the foreign designs bult localy with or without legal license.

Fighter aircraft designed and built in Europe (including Russia and the former Soviet Union), the aircraft built under US license in Europe, as the F-104, F-16 or F-35, ar not allowed to this challenge.

Tankers used for air-to-air refuelling. Combat aircraft capable of buddy-tnanking are allowed only if the tanking equipment is visible.

Jet aircraft designed and used for advanced pilot training, such as T-33, T-37, T-38, T-45, Alphajet, Hawk, jet Provost, Saab105, MB-339, M-346, Yak-130, L-29, L-39, IAR-99, T-50, Galeb. No two seater training versions of the actual combat aircraft, please.

Aviation and aircraft modelling pictures.

Aviation memorabilia: medals, coins, pins, cards, models, decorations and so on.

Towering clouds

Aircraft

War Machines, real or models.

Vehicles powerred by the thrust of a jet or rocket engine. The vehicles must be powerred by the reaction force not by the transmission to wheels or propeller.

Airshow pictures

Any space assets or artifacts (rockets,spaceshuttle, space suits, space vehicles and so on) operational or preserved in a museum.

Here you can find some good instructions on how to take Schlieren optics pictures: https://youtu.be/IZ0bYi9UFv8 Although is not very difficult, it is a kind of unusual topic and we can give it a try, so everybody can learn something interesting. More details on Sclieren photography here: https://en.wikipedia.org/wiki/Schlieren_photography

Diver watches

Military aircraft.

Northern lights

Air Force related pictures: aircraft, people, ground support operations and infrastructure, uniforms, artifacts and so on.

Analog or digital watches glowing in low light.

Combat aircraft builtin Europe.

Airshow pictures.

Lightning bolt

Any MiG fighter aircraft, operational, preserved or scraped.

Pilot helmets.

Air Force related picures - military aircraft, flight line, personnel wearing air force uniforms, weapons, equipment and so on.

Aviarion T-shirts

Aircraft in flight

Vehicle refueling. All types of vehicles are accepted - cars, trains, ships, airplanes and so on. No animals, birds or insects please.

Flight suits worn by aircrews or displayed in a museum, store and so on. Separate elements, as hats, helmets, gloves, boots are accepted.

Airshow

Airborne Warning and Control Aircraft

Only aircraft on floaters.

Airshow pictures.

Aircraft landing gear details. Close-up pictures of the landing gear and wheels / ski's / floaters. No landscapes with aircraft having their gear down, please.

Aircraft with their lights on. The lights must be clearly visible in the image.

Single or multiple aircraft tails. just the.Jtail section, the whole aircraft must not be visible in tJe picture,

Watch tower of a castle, airport tower and so on.

Aircraft performing a low pass. Wheels must be retracted and the aircraft must not be durung take off or landing. Aircraft with non-retractable landing gear must have the flaps up.

Camouflage - people, vehicles, weapons wearing a military camouflage.

Life on the airfield

Military rank captain, ship or aircraft captain, police, firemen captains and so on. The subject must wear an uniform.

Fall colors

The Furin Wind Bell or ‘is an icon of the Japanese culture. The Furin bells have a very distinctive quality of the sound compared to the Western wind chimes., being a single, resonant sound, clear and cool.

Tea as an art

Long exposure lights of any moving ehicle.

Warship

Cocktail

Smoking tires - cars accelerating or braking hard, aircraft landing and so on.

The subject of the picture must be mirrored by a mirror like surface: mirror, water, glass, polished metal, hot air and so on.

Upload your favorite picture of a coffee cup.

Aircraft in inverted flight. The bank anle visible in the image must exceed 90 degrees.

Solar or Moon eclipse.

Ejection Seat

Upload the picture of a battleship or large combat ship. Please do not upload pictures of small ships (frigates, corvettes, destroyers and so on).

My Room

Pictures ilustrating the power of a turbine engine.

Sophistication, a display of good taste, refinement and subtlety.

Street lights

Ice breaking

Hovercraft is "a craft capable of travelling over land, water, mud, ice, and other surfaces. Hovercraft are hybrid vessels operated by a pilot as an aircraft rather than a captain as a marine vessel". (Wikipedia. Ground effect vehicles (GEV) are also aditted to this challenge.

Engine room

Aircraft Control Stick / Wheel as a main subject. Aircraft engine throttles, and helicopter collectives are also admitted to this challenge.

Locomotives, train cars or other railroad vehicles damaged beyond repair or left in decay No injured or dead passengers in the wrecks due to accidents.

SHIP BRIDGES. "The bridge of a ship is the room or platform from which the ship can be commanded. When a ship is underway the bridge is manned by an OOW (officer of the watch) aided usually by an AB (able seaman) acting as lookout. During critical maneuvers the captain will be on the bridge supported, perhaps, by an OOW as an extra set of hands, an AB on the wheel and sometimes a pilot if...

Close up pictures of spinning wheels, propellers and aimilar objects with rotating motion. Entries must have the motion blur of the rotation movement, while the body of the object must be reasonably sharp. The pictures must be taken as close as possible - the images with too distant subjects will be disqualiffied.

Cars and trucks damaged beyond repair. No injured or dead passengers in the vehicles wrecked during accidents.

Images taken only with Pentax cameras.

Aircraft - Close and personal

Pilot / aircrew pins, insignia, badges, patches and name tags with wings.

Wings

Any weapon, natural or man made, ranging from slingshot to aircraft carrieir.

Air bubbles, soap bubbles or any other types of bubbles that you can imagine.

Picture of buterflies from close distance.

Refueling a vehicle system or any other type of refueling that you can imagine.

Any aircraft designed for pilot training, jet or propeller, used by military or civilian flight schools.

Waterfalls, natural or man-made. No water fountains please.

Vintage fighters, no longer in service (as much as possible). Jet or propeller.

Any speed indicator gauge, analog or digital, from cars, trains, boats, airplanes and so on. Indicators from any other devices are allowed as for instance for cameras), or traffic radar. No traffic speed signs please.

The picture of sea viewed from an aircraft in flight.

Single engine propeller or jet light/ultralight aircraft, general aviation or military. Drones and gliders are allowed, No parachutes, paragliders, balloons, fighters, airliners, large multiengine aircraft and so on.

Picture taken inside an aircraft. All kinds of interior pictures are allowed: cockpit, passenger cabin, cargo / weapons bays, landing gear bays, equipment or engine compartments and so on.

Formation of two or more aircraft flying together. No picture of single aircraft, aircraft lying on opposite directions or aircraft that just happened to apppear in the same frame, but that are not an organized formation.

Colorful picture of the sea, on the surface ur underwater. Sea life, ships, buildings, people or any other objects could be visible.

Military aircraft designed to carry troops or equipment. No helicopters or tilt rotor aircraft please. Pictures from outside, inside or details of the aircraft.

Upload a picture to depict the joy of the Christmas celebration. Could be anything related to Christmas: the traditional dinner or lunch, Christmas decorated trees, family or public parties, gifts, decorated houses, indooor decorations and so on.

Picture of sea during before sunrise or after sunset. Pictures with the solar disk slightly visible could be acceptable but should not exceed half of its size. Ships, buildings, people or any other objects could be visible. Twilight: "the soft glowing light from the sky when the sun is below the horizon, caused by the reflection of the sun's rays from the atmosphere" (Wikipedia).

Upload the picture of a lone tree. Forest or other group of trees should not be present in the picture. No other close constructions (buildings, poles and so on) are allowed in the pictures, but humans, animals vehicles are acceptable.

Upload the icture of a woman during one of the appiest days of her life.

Upload a picture of a city downtown, that captures the spirit of that city.

Classic or jet figher aircraft, operational or not.

Pictures taken with a mobile phone, phablet or tablet that are using Android or Windows operating systems. Apple devices are not allowed to this challenge as they just had a dedicated one.

Upload a pictures taken inside a library.

Pictures taken with an iPhone

Wedding Cake

Sports car

Upload the picture of a MiG-15 or her relatives (S-102), operational or displayed in a museum. Aircraft models, T-shirts, art-prints, books or any other items that remind the venerable MiG-15 are admitted.

Upload a panoramic image of an urban area that has a relatively wide aspect ratio. In camera panoramas are preferred but manually stitched images are allowed. Outdoor or indoor images are accepted.

Ever visited South Africa or living there? Upload a picture that best express that corner of the world. Challenge dedicated to George Veltchev.

Wind power - any picture to express the force of the blowing wind.

The fastest jet aircraft ever built, Lockheed SR-71 Blackbird still holds some speed and altitude world's records. Upload the picture of a SR-71 or her relatives (A-12, YF-12, M-21), operational or displayed in a museum. The D-21 drone, aircraft models, T-shirts, art-prints, books or any other items that remind the SR-71 are admitted.

Picture of a individual house or apartment, taken from inside or outside. No groups of houses, street view or entire apartment buildings please.

Solar power - any picture to express that.

Apple in your view.

Flying Machines of any kind.

Our Daily Bread in your view.

Airshow Season has come - upload a picture that best describes the spirit of an airshow. Any subject related to an airshow is acceptable: aircraft on the ground or in flight, crews preparing the flight or aboard thei aircraft, mechanics getting the aircraft ready for flight, ground controlers, people attending, etc.

Pictures taken with a Pentax DSLR camera.

I;m single!

High-dynamic-range imaging (HDRI or HDR) is a technique used in imaging and photography to reproduce a greater dynamic range of luminosity than is possible with standard digital imaging or photographic techniques. The aim is to present the human eye with a similar range of luminance as that which, through the visual system, is familiar in everyday life. - Wikipedia. Upload a HDR picture,...

Upload the pictiure of a national flag.

Your view on time and time passing.

A pyramid shaped object, building or setup. Things like a human pyramid or a pyramid of objects are allowed.

Upload a picture of your other camera.

Upload the picture of a royal crest. It could be anything: on a panel, clothing, plates, seals and so on.

Upload the picture of a car instrument panel. Buses, trucks and other wheeled vehicles are also allowed to this chalenge.

Pictures taken with a mirrorless Sony Alpha camera.

Military or civilian pilot patches. Only cloth patches are allowed, no metalic, plastic or any other hard pins, logos and so on.

Spiral shaped natural or man made objects, buildings, living creatures.

Pictures of telescopes used for astronomy purposes. All kinds of telescopes are allowed, including large radiotelescopes or large observatory buildings that house the telescopes.

The war veterans fought for our freedom. Upload the picture of one or more war veterans, in uniform or not.

Picture of a Chevrolet Camaro. Models, T-shirts or any other items that remind the Chevrolet Camaro are admitted.

The venerable MiG-21 was the most produced supersonic jet fighter, hundreds of them being still in service more than 60 years after the maiden flight of the first Ye-4 prototype on 16 June 1955. Upload the picture of a MiG-21 fighter or any derivative. Models, T-shirts or any other items that remind the MiG-21 are admitted.

Numerous monuments, statues, memorials commemorate those heroes who sacrificed their lives for our freedom Upload the picture of such a monument.

As the spring is coming upload a picture of the fresh green.

The subject of the challenge is the airport. Upload the picture of an airport runway, control tower or any other airport infrastructure element.

In this challenge each user is entitled to upload two pictures that show the same subject before and after an action (for instance a city area before and after a storm). As an option one could combine the two pictures in a single one, divided or not. Any subject is allowed, just unleash your creativity.

Picture of a vertical take off jet aircraft, like Harrier, VJ-101, VAK-191B, Balzac V, Yak-141 and so on. No propeller aircraft, helicopters or convertible aircraft.

Upload a panoramic image that has a relatively wide aspect ratio ratio. In camera panoramas are preferred but manually stitched images are allowed.

Picture of a F-15 Eagle fighter. Models, T-shirts or any other items that remind the F-15 Eagle are admitted.

Any picture you consider nice, no limits or rules.

Upload the picture of an aircraft or helicopter carrier. Combat ships not dedicated as carriers, with flight decks for a single or two helicopters are not allowed.

Aircraft on the final approach with gear and flaps extended. No fly-by please. Pictures from the cockpit are allowed but it must be on the short final, with the runway clearly visible (see the sample picture).

Upload the picture of a guitar.

Upload a close-up picture of an aircraft, showing a specific detail. Could be any interior or exterior partȘ cockpit dials/screens, controls, engines or engine details, parts of the landing gear,, wings or fuselage, other small details. No general overview of the aircraft or large parts of it. Preferably pictures displaying no more that a quarter of the entire aircraft body.

The picture of an Eurofighter Typhoon fighter aircraft. No models or mok-ups please.

Night sky with stars. No moon please but ground objects might be visible.

Your idea of motion.

Upload a picture to depict the Christmas decorations. Could be anything related to Christmas deorations: trees, decorated houses, outdoor or indoor decorations and so on.

Flying in December pictures. Any picture related to aviation and human flight, taken between 1st and 31st of December, based on the EXIF file information. The year doesn't matter.

"A lightning strike (or is an electric discharge between the atmosphere and an earth-bound object. They mostly originate in the thundercloud and terminate on the ground, called cloud to ground lightning." - Wikipedia. Submit a picture of a lightning (natural or artificial). The artificial lightning must be generated in a large scale laboratory. No small scale electric arcs / discharges.

November sky pictures. All pictures must be taken between 1st and 30th of November, based on the EXIF file information. The year doesn't matter.

Flying in November pictures. Any picture related to aviation and human flight, taken between 1st and 30th of November, based on the EXIF file information. The year doesn't matter.

Upload the picture of a "toy" for grown ups. It could be any object used for a hobby: sports vehicle, motorcycle, boat, private airplane, cameras, musical instruments and so on. Persons, animals or other living creatures are not allowed as the main subject of this challenge. No offensive shots please.

Upload the picture of a model aircraft, ship, car, train and so on.

Upload the picture of a military style wristwatch / tactical watch. Any model is accepted, contemporary or old, but it has to be dedicated for military operations.

Upload a picture of a man made motor vehicle in high speed. The image have to express a sense of high velocity motion. No stationary vehicles please.

Flying in September pictures. Any picture related to aviation and human flight, taken between 1st and 30th of September, based on the EXIF file information. The year doesn't matter.

Upload the picture of an artificial water curtain.

Pictures of the sky during night time.

You witnessed the space launch preparation or the actual rocket launch? Upload the picture of such a spectacular event. Only real space vehicles are allowed to this challenge. No model rockets, weather rockets, military rockets or missiles and so on.

Flying in August pictures. Any picture related to aviation and human flight, taken between 1st and 31st of August, based on the EXIF file information. The year doesn't matter.

Upload the picture of a fireworks show.

Aviation museums, aircraft preserved or used as gate-guards. No models or mock-ups please, only real aircraft or rockets, in any state.

Upload a picture of a mountain top surrounded or shrouded by clouds. Pictures taken from the air (from aircraft or drone in flight) are preferred, but those taken from the ground will not be rejected.

July sky pictures. All pictures must be taken between 1st and 31st of July, based on the EXIF file information. The year doesn't matter.

Drone pictures - image taken by a drone or of a drone.

Flying in July pictures. Any picture related to aviation and flying, taken between 1st and 31st of July, based on the EXIF file information. The year doesn't matter.

June sky pictures. All pictures must be taken between 1st and 30th of June, based on the EXIF file information. The year doesn't matter.

The portrait of a civilian or military airman. The airman must be must be in the cockpit or next to the aircraft, preparing for flight, in flight or returning from a flight. If the airman wears an uniform the aircraft presence in the picture is not mandatory.

Flying in June pictures. Any picture related to aviation and flying, taken between 1st and 30th of June, based on the EXIF file information. The year doesn't matter.

May sky pictures. All pictures must be taken between 1st and 31st of May, based on the EXIF file information. The year doesn't matter.

Water and rocks

Military cargo aircraft or their derivatives used for special missions (tankers, electronic warfare, airborne early warning, gunships and so on). No civilian airliners or aircraft designed for other roles than airlift.

Flying in May pictures. Any picture related to aviation, taken between 1st and 31st of May, based on the EXIF file information. The year doesn't matter.

Classic propeller airliners. No modern jets or military cargo aircraft please. Only propeller driven models in flying condition or not. Aircraft models are allowed. Current short range turboprops might enter the challenge, but it would be preferred to avoid them.

Propeller fighter aircraft. No jets please, only propeller driven models in flying condition or not. Modern remakes or aircraft models are allowed.

April sky pictures. All pictures must be taken between 1st and 30th of April, based on the EXIF file information. The year doesn't matter.

The picture of an airfield runway viewed the ground or from an aircraft in flight. Grass/snow/ice runways and taxiways are accepted.

Moonscape pictures - close ups of the Moon close-up taken with long focal lenses or landscape pictures taken on Earth of lunar looking areas.

March sky pictures. All pictures must be taken between 1st and 31st of March, based on the EXIF file information. The year doesn't matter.

"MiG aircraft are a staple of the Soviet and Russian air forces, and the Soviet Union sold many of these aircraft within its sphere of influence. They have been used by the air forces of China, North Korea, and North Vietnam in aerial confrontations with American and allied forces, and form part of the air forces of many Arab nations." (Wikipedia) Upload a picture of any MiG aircraft or...

Show your national flag.

February sky pictures. All pictures must be taken between 1st and 29th February, based on the EXIF file information. The year doesn't matter.

This challenge is to show an aircraft ground crews in action. The ground crew must be working in the aircraft or next to it. Other aircrew may be visible but the ground crew(s) must be the the main subject. No overall airport or aircraft views with tiny people please.

F-16 Fighting Falcon is a single-engine multirole fighter aircraft originally developed by General Dynamics for the United States Air Force (USAF). Designed as an air superiority day fighter, it evolved into a successful all-weather multirole aircraft. Over 4,500 aircraft have been built since production was approved in 1976.[3] Although no longer being purchased by the U.S. Air Force, improved...

Any propeller is allowed to this challenge. This might include propeller aircraft, UAVs and helicopters, ship propellers, windmills, fans and so on.

Military or civilian aircrew in action: pilots, navigators, mechanics, flight attendants and so on. Just genuine aircrew, not look alike. The aircrew must be in the cockpit, next to the aircraft, or in a specific airfield facility, preparing for flight, in flight or returning from a flight. The aircrew must be the the main subject and must wear their flight gear or an uniform.

People who travel by air: in airports anxiously waiting to board, in the airplane or next to it. Aircrew pictures are admitted, although they will be the subject of the next challenge.

Upload your best picture of a city, taken from an aircraft or from a drone in flight. Elements of the aircraft might be visible. Pictures from top of buildings, hills, bridges or any other grond located objects are not allowed.

White trees, covered with snow.

January sky pictures. All pictures must be taken between 1st and 31st January, based on the EXIF file information. The year doesn't matter.

December night pictures. All pictures must be taken between 1st and 31st December, based on the EXIF file information. The year doesn't matter. Sunset to sunrise pictures - twilight is allowed but Sun must not be visible in the image.

Upload a picture to depict the 2014 family Christmas celebration. Could be anything related to family and Christmas: the traditional dinner or lunch, trees, family parties, gifts, decorated houses, indooor decorations and so on. No public parties, trees or public decorations/lighting please.

Aviation or space museums, aircraft preserved or used as gate-guards. No models or mock-ups please, only real aircraft or rockets, in any state.

Upload a night sky picture. Twilight pictures are allowed bus sun must be below the horizon.

December sky pictures. All pictures must be taken between 1st and 31st December, based on the EXIF file information. The year doesn't matter.

November sky pictures. All pictures must be taken between 1st and 30th November, based on the EXIF file information. The year doesn't matter.

Pictures taken with Sony A6000 cameras.

"A tall ship is a large, traditionally-rigged sailing vessel. Popular modern tall ship rigs include topsail schooners, brigantines, brigs and barques. "Tall Ship" can also be defined more specifically by an organization, such as for a race or festival." (Wikipedia). No small boats, yachts or other types of ships or boats that don't meet the definition above.

Upload a picture that illustrates the effort to reach new frontiers in the sky, through the development of aviation and astronautics. Monuments, statues or artifacts that illustrate the will to fly are accepted. No skyscrapers, buildings, trees, birds, flying insects or other tall objects that deviate from the main idea of the challenge please.

Wrecked ships: abandoned, decommissioned, sunk.

Picture of a house or group of houses taken at night time. Twilight pictures are accepted. Only houses allowed in this challenge. Apartment blocks are not admitted.

Wrecked aircraft: abandoned, decommissioned, crashed.

Upload the picture of a hot air balloon or a blimp. The actual aircraft must be the subject of the picture. Landscapes with very distant balloons/blimps are not allowed. Try to upload a good quality shot and stay with the theme.

Picture of a parked vehicle (car, bicycle, airplane, train, boat).

Accident, incident and crash related photos. Small and/or funny accidental events are allowed (i.e. spilled coffee). No graphic images please. I will remove the images that I consider offensive, too graphic or unsuitable.

Airliner is an aircraft intended for carrying multiple passengers or cargo in commercial service. Small aircraft, as private, air taxis or business jets that are not registered with a commercial airline and do not fly on regular routes are not allowed to this challenge. The picture could be taken from outside or depict the interior of the aircraft - passengers and crews might appear in the...

Bridges at night time - twilight shots are allowed.

"Business jet is a jet aircraft designed for transporting small groups of people. Business jets may be adapted for other roles, such as the evacuation of casualties or express parcel deliveries, and some are used by public bodies, government officials or the armed forces" - Wikipedia. Please upload the picture of a business jet. Other small aircraft, as private turboprops, air taxis or ULMs...

Upload the picture of the Black Sea - the picture may include the entire range, from resorts filled with summertime tourists to the frozen waters during the harsh region winter.

The dams are barriers that impound water streams and normally they are used to retain the water. Upload the picture of a dam - the picture may include the entire range, from the huge hydro-plant dams to the beaver built ones or natural dams.

The second longest river in Europe - 2,860 km, Danube flows through four national capital cities: Vienna, Bratislava, Budapest and Belgrade. The Danube empties into the Black Sea via the gorgeous Danube Delta in Romania.

July heat pictures. They must express something about the heat of this hot month of the year.

Wings of all kind. Bird, airplane, insect or anything else, the main feature visible must be the wing(s).

Upload a picture of Easter decorated egg(s).

Aircraft performing a night or twilight landing.

The purpose of this challenge is to show your view of faster than sound speed. Could be a supersonic jet, shock wave, rockets, meteors dashing through the atmosphere, bullets and so on.

The picture of a ship viewed only from an aircraft in flight. Please do not upload picture taken from bridges, buildings or clifftops. The ship(s) must be the main subject of the picture.

Aviation museums, aircraft preserved or used as gate-guards.

Showcase your iPad, functional or not, shining or shattered. Only Apple iPads allowed to this challenge.

Once known as the "Little Paris", Bucharest has many hidden gems in terms of buildings, monuments, parks and many other. Upload a picture that best describes the Romanian Capital city - everything is acceptable, whether is people or buildings or something else.

Upload the picture of a rocket launch? Any rocket is acceptable: space rocket, model rocket, weather rocket, military rocket, space shuttle and so on.

Upload the picture of a turbine engine. No turbocharged piston engines please.

The subject of this challenge is the airport terminal building(s) or an airport control tower viewed from outside or inside, after sunset.

Upload the picture of a pilot wristwatch / aviation wristwatch (e.g. Breitling Emergency, Breitling Navitimer, Hamilton Flight Timer, Seiko Flightmaster, IWC Big Pilot’s Watch). Any model is accepted, contemporary or old, but it has to be dedicated for aircrew.

Upload the picture of an aircraft on the ground or in flight during winter. Pictures from the cockpit / flight deck are allowed but a significant part of the airplane must be visible (dashboard, wing, engine, fuselage, tail). Snow, ice or people wearing winter clothes must be visible in the picture.

Upload a picture to illustrate the act of a person thinking. It could be anything - a person or a work of art, provided that you make a proper description.

Picture of a space museum

Upload the picture of a Swarowski crystal or from your collection or a Swarowski crystal decorated object (the crystals must be visible). Crystals displayed in a store window are admitted but they have to be the main subject of the picture.

Upload the picture of an engraved crystal cube from your collection. Crystals displayed in a store window or sold at the street corner are admitted but they have to be the main subject of the picture.

Upload the picture of a Lego toy from your children's collection. Only Lego® products are admitted to this challenge. Pictures of Lego-like will be disqualified.

Aircraft that made history through long range bombing missions. Only heavy and medium bombers are admitted to this challenge.

The picture of a runway viewed only from an aircraft in flight. Grass/snow runways are accepted.

Upload a picture that best describes the spirit of an airshow. Any subject related to an airshow is acceptable: aircraft on the ground or in flight, crews preparing the flight or aboard thei aircraft, mechanics getting the aircraft ready for flight, ground controlers, people attending, etc.

Upload your best picture of a city at dusk, night or dawn, taken from an aircraft in flight. City lights must be visible in the picture.

Upload the picture of a hot air balloon or a blimp. The actual aircraft must be the subject of the picture and it should take at least 10% of the area of the picture. Try to upload a good quality shot and stay with the theme.

Upload a picture that best describes modeling as a hobby (aircraft, ships, cars, trains and so on).

Upload the picture of an aircraft on the ground or in flight during sunset / sunrise. Pictures from the cockpit / flght deck are allowed but a significant part of the airplane must be visible (dashboard, wing, engine, fuselage, tail).

Upload a picture of a weird object that fly or can fly. The subject must be capable of sustained flight. Any thing related to the subject is acceptable: unusual aircraft on ground or in flight, strange looking balloons, animals, birds, UFOs, etc.

The picture of a bridge viewed only from an aircraft in flight.

Upload a picture that illustrates the dream to fly.

Parachutes, para-gliders, hang gliders and other like these.

The picture of a forest viewed only from an aircraft in flight.

Upload a picture to describe flight simulation - it could be anything from a home made computer simulation station to a full scale simulator. Old simulators displayed in museums are accepted.

Upload the picture of a beautiful landscape that caught your eye. The picture must be taken from an aircraft in flight.

Upload a picture that best describes your idea about flight. The challenge is NOT restricted to aircraft.

Upload a picture that best describes aircraft modeling as a hobby.

Upload the picture of a bird of prey. Any bird that hunts for food is accepted - hawks, eagles, buzzards, harriers, kites, falcons, ospreys, condors, vultures as well as night birds, like owls. Or the Klingon Bird of Prey...

Upload the picture of an aircraft dashboard, preferably in flight. Both civilian or military are accepted.

Upload the picture of an aircraft in inverted flight. Both civilian or military are accepted.

This challenge is to show an aircraft mechanics in action. The mechanic must be working in the aircraft or next to it. Other aircrew may be visible but the mechanic(s) must be the the main subject.

The picture of a stretch of water viewed from an aircraft in flight - sea, lakes (natural or artificial) rivers. No swimming pools or fountains please.

Upload the picture of a glider on the ground or in flight. Pictures from the cockpit are allowed but a significant part of the glider must be visible (dashboard, wing, engine, fuselage, tail). Both civilian or military are accepted. No hang gliders or paragliders please.

The picture of clouds viewed from an aircraft in flight.

"Never was so much owed by so many to so few" - Winston Churchill. Upload a picture related to the famous Battle of Britain - the first major campaign to be fought entirely by air forces in 1940. Both sides, British and German can be represented: people, aircraft, places, memorials.

Spacecraft of any kind: prepared for launch, during launch, on the orbit around Earth, preserved in a museums or displayed in public places. No UFOs, spaceships from movies or other fantasy spacecraft.

Old aircraft built before 1960. No modern remakes please, only original models in flying condition or not.

Airports are among the most promnent features of a city, many times being small cities themselves. The subject of the picture must be the airport terminal building(s) viewed from outside or inside.

The picture of a mountain area viewed from an aircraft in flight.

Aviation museums, aircraft preserved or used as gate-guards.

Once known as the "Little Paris", Bucharest has many hidden gems in terms of buildings, monuments, parks and many other. Upload a picture that best describes the Romanian Capital city - everything is acceptable, whether is people or buildings or something else.

The subject of the picture must be the airfield control tower. It could range from the real control tower of a full scale airport to the formal control tower of a small or improvised airfield (meaning in many cases a seat, a table and a radio...).

Aircraft smoke trails during airshows, high altitude contrails and not only... The only rule is that they have to be aircraft related.

The aviation history is scattered with many unfortunate events in which aircrews lost their lives. Numerous monuments, statues, memorials remember us these heroes. Upload the picture of such a monument.

The subject of this challenge are people watching an airshow. If possible, upload a picture taken from an aircraft in flight that's overflying the area. Close-ups of people in the crowd are acceptable (people with cameras, children, etc).

Upload your best picture of a city, taken from an aircraft in flight.

Helicopters and rotating wing aircraft. The actual aircraft must be the subject of the picture and it should take at least 10% of the area of the picture. Try to upload a good quality shot and stay with the theme.

Aircraft cockpits are the subject of this challenge. The crew could be present in the cockpit and if the systems are on the better it is. The picture of the acockpit while the aircraft is in flight are desirable and it will bring more realism and sense of action.

There are just a few things that could be more spectacularthan a sunset/sunrise viewed from the air. Upload the picture of a sunset/sunrise taken from an airplane in flight.

Space Shuttle - try your best: shuttle launches, carried piggyback on the B-747 SCA, shuttle at touch down or displayed in a museum.

This challenge is to show a flight attendant in action. The flight attendant must be in the aircraft, next to the aircraft, preparing for flight or in an airport. Other aircrew may be visible but the flight attendant(s) must be the the main subject.

Absolutely no connection with the overall specifics of the "Sky is the limit" series, just a wish of my 10 years old son - Lego toys. Upload the picture of a Lego toy from your children's collection. If you want to stay with the "Sky is the limit" theme upload an aircraft/airfield/spacecraft from the "Lego City", "Lego Creator", "Mars Mission" or "Star Wars" collections. However this is not...

Upload the picture of a hot air balloon or a blimp. The actual aircraft must be the subject of the picture and it should take at least 10% of the area of the picture. Try to upload a good quality shot and stay with the theme.

Aircraft landing - try your bes: heavy smoke at touch down, hard tactical landings on summary prepared landing strips, helicopters landing in heavy dust or snow clouds, dangerous runways, heavy crosswind in Hamburg, drag chutes, carrier landings or the beautiful St Maartens.

Upload the picture of an aircraft on the ground or in flight during sunset / sunrise. Pictures from the cockpit / flght deck are allowed but a significant part of the airplane must be visible (dashboard, wing, engine, fuselage, tail).

The subject of this challenge is the runway lighting: Approach Lights, Runway Threshold/End, Edge and Centreline Lights. To add to the composition, aircraft might be present on the runway but it is not mandatory.

Show a military jet aircraft with afterburner on. Images taken in sunset or dim light conditions are preferable.

This challenge is to show a military or a commercial pilot in action. The pilot must be in the cockpit or next to the aircraft, preparing for flight, in flight or returning from a flight. Other aircrew may be visible but the pilot(s) must be the the main subject.