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Airplane / Helicopter

An aircraft is heavier than air for flights in the atmosphere (and outer space (e.g. An orbital aircraft)), which uses the airframe's aerodynamic lift to keep itself in the air (when flying within the atmosphere) and the thrust of the power (propulsion) installation for maneuvering and compensating for the loss of total mechanical energy on drag. 

A rotary-wing aircraft, in which the lift and thrust necessary for flight are created by one or more main propellers driven by an engine or several engines. They differ in maneuverability, the ability to hover and almost vertical takeoff.


Even an ordinary plane can be taken for a UFO at an unusual viewing angle, when illuminated by sunlight at sunset or dawn, when bright light from the Sun is reflected on it, as well as in a photo, especially if it does not leave a condensation trail.

There are also unusual aircraft designs. In the photo, it may look like a small dot with a metallic luster, a dark dot, a small dark or silver elongated object (cigar-shaped), etc.

It is especially often mistaken for a UFO plane without a condensation trace, if it flies next to the plane leaving a trace (the difference in size is almost invisible to the eye).

Often planes are mistaken for UFOs due to external lighting equipment, especially at night. In addition to the standard red-green-white illumination, blue lights at the end of the blades are used in night modifications of some helicopters.

Helicopter flights over and near populated areas can be caused by various reasons, in addition to military exercises, air excursions, preparation for a holiday, etc.this can be, for example, thermal imaging (infrared aerial photography) of thermal communications of the city, monitoring of the Ministry of Emergency Situations, police, and much more.

Also, various devices attached to an airplane or other aircraft can be mistaken for a UFO. For example, AWACS (Aviation Radio Detection and Guidance Complex), OGAS (Lowered sonar stations) on helicopters, etc.

The aircraft can perform various maneuvers and aerobatics both independently and in a group. To an outside observer, this may be perceived as "strange behavior for an airplane".

Most often, this is the training of pilots ' skills on military aircraft. But also, for example, an unusual flight can be observed during scientific research. Here is an example with the study of clouds:

There are five small holes in the nose of the C-130 aircraft, each of which is connected to a pressure sensor that measures the wind. By performing certain maneuvers, the NAAMES team can calibrate and verify vertical wind measurements, which are combined with humidity measurements to study particles in and around clouds. 

The following maneuvers ("Tail turns") affect the horizontal pressure sensors when the aircraft moves from side to side in a crab motion. "Porpoise" is a maneuver in which the aircraft moves up and down, using a vertical pair of pressure sensors on the nose. The purpose of the "Bow Tie" is to map out the vortex features and variability of the ocean around the ship in the least number of passes) they allow scientists to collect data at different heights and cover as much of the area as possible, while confirming the accuracy of scientific measurements.

Similar movements of the aircraft are also used for calibration of NASA instruments.

The HZ-1 aerocycle was built by De Lackner in the mid-1950s. Originally called the DH-4 Helivector, it was later renamed the HZ-1 Aerocycle and resembled a hybrid of a helicopter, motorcycle and outboard motor.

The HZ-1 aircraft was equipped with a 40 hp engine, which was mated to two coaxially arranged propellers. The screws with a diameter of 4.6 meters rotated in opposite directions, which allowed avoiding the rotation of the platform itself, on which the pilot was standing. At the same time, the pilot was positioned vertically directly above the rotating propeller blades, a steering wheel similar to a motorcycle was provided to control the device. With its help, the pilot had to change the speed, direction and altitude of the HZ-1 flight (in order to make a turn, it was necessary to tilt the entire aircraft in the right direction — just as it is done on a motorcycle).

It was assumed that the US military would be able to effectively use this flying platform only after a 20-minute briefing. But test pilot Selmer Sandbai, who tested the HZ-1, had a different opinion. In particular, he noted:

"It took me just one flight to understand that it would be damn difficult for an ordinary person to cope with this design."

All the identified shortcomings led to the closure of this program. At least one such flying platform has survived to this day, which is displayed as a museum exhibit.

Orbital plane (OS), aerospace plane (VKS), aerospace, aircraft — winged aircraft airplane schematics, or coming into orbit of an artificial satellite of the Earth by means of vertical or horizontal start and returning with her, after achieving targets, making horizontal landing on the airfield, actively using while reducing the lifting force of the glider. It combines the properties of both an airplane and a spaceship.

  • Kosmoplan-OS (VKS) as the second stage of an aerospace system (AKS), put into orbit not only by its own engines, but also by means of a launch vehicle (RN), as well as rocket stages-accelerators, either by a winged 1st stage of the AKS at a vertical launch or by a booster aircraft or by a winged 1st stage of the AKS at a horizontal launch. In systems with a horizontal launch, the air launch technology is used to launch spaceplanes. In fact, the first in the history of realized spaceplanes that performed suborbital manned space flights and for 20 years the only AKS was the American hypersonic rocket plane North American X-15 of the 1960s (13 of its flights above 80 km (US standards), and 2 of them, in which the space limit of 100 km was exceeded (according to FAI world standards), were recognized as suborbital manned space flights, and their participants were astronauts).
  • A spaceship is a single-stage AKS that enters orbit at the expense of its own engines during a vertical or horizontal launch. Due to the need for an order of magnitude more complex propulsion and structural technologies when creating spaceships, none of the spacecraft projects has been implemented to date. One of the first detailed projects of AKS and spaceships was the unrealized project of Zenger (in the late 1930s .) on the creation of a partially-orbital combat spacecraft-bomber "Silberfogel" in Nazi Germany.

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