Were helicopters used in second world war?

Answer 1

The Germans:

The Focke-Achgelis FA 330 Bachstelze (English: Wagtail) was a type of rotary-wing kite, known as a gyroglider or rotor kite. They were towed behind German U-boats during World War II to allow a lookout to see farther.

Because of their low profile in the water, the submarines could not see more than a few miles over the ocean. To solve this, the German admiralty considered a number of different options, including a folding seaplane (Arado Ar 231). In the end, they chose the FA 330, a simple, single-seater autogyro kite with a three-bladed rotor.

The FA 330 could be deployed to the deck of the submarine by two people and was tethered to the U-boat via a 150 m (500 ft) cable. The airflow on the rotors as the boat motored along on the surface would spin them up. The kite would then be deployed behind the U-boat with its observer/pilot aboard, raising him approximately 120 m above the surface where he could see much farther; 25 nautical miles (46 km) compared to the 5 nautical miles (9 km) visible from the conning tower of the U-boat. If the U-boat captain was forced to abandon them on the surface, the tether was released and the FA 330 descended slowly to the surface.

When not in use, the FA 330 was stowed in two watertight compartments aft of the conning tower. Recovering, dismantling, and stowing the FA 330 took approximately 20 minutes and was a difficult operation.

On the Allied side:

The YR-4B was full-scale wind tunnel-tested at Langley Army Airforce Base in Hampton, VA in 1943--JC Lovell, father of astronaut Lovell, was a member of the NACA team that undertook this testing. They called themselves the 'Society of Rotor Wretches'--I have the group ID badge created by this team bearing J. Lovell's name upon it, and HIS copy of Notes on Helicopter Design Theory, by Alexander Nikolsky and translated from the Russian original, and bears on the inside cover both JC Lovels signature and then current address in Hampton, VA

On 22-23 April 1944, U.S. Army Lieutenant Carter Harman of the 1st Air Commando Group conducted the first combat rescue by helicopter using a YR-4 in the China-Burma-India theater. Despite the high altitude, humidity, and capacity for only a single passenger, Harman rescued a downed liaison aircraft pilot and his three British soldier passengers; two at a time.[4] On 22-23 January 1945, another rescue by the R-4 involved several legs for refueling and navigating through passes between mountains nearly 10,000 feet (3,000 m) tall, to reach a weather station located at an elevation of 4,700 feet (1,400 m). The higher than normal altitude required a downhill run of 20 ft (6.1 m) to get airborne.