Piasecki HU-21

Piasecki HU-21
País	Eua
Tipo	Helicóptero de carga
Período	1952-1967
Fabricante	Helicóptero Piasecki

O Piasecki H-21 Workhorse/Shawnee is an American helicopter, the fourth of a line of tandem rotor helicopters designed and built by Piasecki Helicopter (later Boeing Vertol). Commonly called “the flying banana”, it was a multi-mission helicopter, utilizing wheels, skis, or floats. The H-21 was originally developed by Piasecki as an Arctic rescue helicopter. The H-21 had winterization features permitting operation at temperatures as low as −65 °F (−54 °C), and could be routinely maintained in severe cold weather environments.

Fonte: Piasecki HU-21 na Wiki

Piasecki HU-21B Anda por aí
Fotógrafo	Cees Hendriks
Localização	Desconhecido
Fotos	73

Click on a photo and use the mouse scroll to view all photos

Espere, procurando fotos do PIASecki HU-21 para você...

Piasecki HH-21B Workhorse
Fotógrafo	Vladimir Yakubov
Localização	Museu da Base Aérea de Travis
Fotos	182

Piasecki HH-21B Cavalo de batalha

Carregar mais...

Espere, procurando fotos do PIASecki HU-21 para você...

CH-21B Shawnee Walk Around
Fotógrafo	Michael Supko
Localização	Museu Americano do Helicóptero em West Chester, PA
Fotos	22

CH-21B Shawnee

Carregar mais...

Veja também:

Piasecki H-21C Workhorse Walk Around
Fotógrafo	Randy Ray
Localização	Museu Do Ar e do Espaço pima
Fotos	34

Click on a photo and use the mouse scroll to view all photos

Piasecki H-21C Shawnee (Vertol V-43A) Walk Around
Fotógrafo	Burhand Donke
Localização	Desconhecido
Fotos	59

Piasecki H-21C Shawnee

Carregar mais...

The Kinked Workhorse

O Piasecki HU-21 (later redesignated the H-21 Workhorse/Shawnee) was a revolutionary tandem-rotor helicopter that solved a major early problem in aviation: center-of-gravity limits. By placing a rotor at each end of the fuselage, Frank Piasecki created an aircraft that could carry heavy loads anywhere in its cabin without becoming unstable. Its distinctive “kinked” fuselage was designed to prevent the two massive rotors from striking each other. Though it looked awkward, it was the first helicopter capable of carrying significant numbers of troops, making it a vital asset in the early days of air assault and Arctic rescue.

Attribute	Technical Specification (H-21C / CH-21C)
Papel	Multi-mission Transport / SAR
tripulação	2 (Pilot and Co-pilot)
Capacidade	20 troops or 12 stretchers
First Flight	April 11, 1952
Usina	1 × Wright R-1820-103 Cyclone radial engine
Horsepower	1,425 hp (1,063 kW)
Maximum Speed	127 mph (204 km/h)
Gama	265 miles (426 km)

Design Highlights: Tandem Power

The “Banana” Bend: The fuselage was curved upward in the rear to ensure that the rear rotor sat higher than the front rotor. This prevented the rear blades from catching the turbulent “wash” of the front blades and, more importantly, prevented the two sets of blades from colliding during flight maneuvers.
Single Engine, Dual Rotors: Despite having two rotors, the H-21 only had one engine. It was mounted in the middle/rear of the fuselage, with long driveshafts running to the front and rear gearboxes. If the engine failed, both rotors would continue to spin together for a safe autorotation.
Arctic Adaptability: The H-21 was often equipped with large “snowshoe” floats over its wheels, allowing it to land in deep snow or marshy tundra without sinking. This made it the primary support aircraft for the Distant Early Warning (DEW) Line in the Arctic.
All-Metal Strength: Unlike many helicopters of the 1940s that used fabric-covered frames, the H-21 was a fully stressed-skin metal design, making it durable enough for frontline combat operations.

Combat and Legacy

The First “Gunships”: In the early stages of the Vietnam War, the U.S. Army experimented with arming the H-21 Shawnee. They mounted .30 and .50 caliber machine guns in the doors and even experimented with fixed forward-firing rockets, paving the way for the dedicated attack helicopters that followed.
French Action in Algeria: The French Air Force used the H-21 extensively during the Algerian War. They were among the first to prove that helicopters could be used to rapidly deploy troops directly into the middle of a battle (vertical envelopment).
Heavy Metal Vibrations: The H-21 was notorious for its vibration. Because of the long driveshafts and massive moving parts, pilots often joked that if the “Banana” stopped shaking, it meant the engine had died.
Successor to the Crown: The H-21 proved that the tandem-rotor concept was superior for heavy lifting. This design lineage led directly to the Boeing CH-46 Sea Knight and the legendary CH-47 Chinook, which still dominates the heavy-lift world today.