Lockheed D-21

Un drone rapide, le Lockheed D-21 sur Wikipedia de langue anglaise

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The [Vous devez être inscrit et connecté pour voir ce lien] D-21 was a [Vous devez être inscrit et connecté pour voir ce lien] 3+ [Vous devez être inscrit et connecté pour voir ce lien].

The drone was originally designed to be launched off the back of its [Vous devez être inscrit et connecté pour voir ce lien]-based M-21 aircraft. Development began in October 1962.

Originally known by the Lockheed designation Q-12, it was intended for reconnaissance missions deep into enemy airspace.

The D-21 was designed to carry a single high-resolution photographic camera over a pre-programmed path, then release the camera module into the air for retrieval, followed by the drone's self-destruction.

^{[Vous devez être inscrit et connecté pour voir ce lien]} Only four operational flights were made over the [Vous devez être inscrit et connecté pour voir ce lien] before the program was cancelled in 1971.

Development

In the early 1960s, Lockheed had developed the Mach 3 [Vous devez être inscrit et connecté pour voir ce lien] reconnaissance aircraft for the [Vous devez être inscrit et connecté pour voir ce lien].

After the [Vous devez être inscrit et connecté pour voir ce lien] of [Vous devez être inscrit et connecté pour voir ce lien]' [Vous devez être inscrit et connecté pour voir ce lien] in 1960, a number of different concepts were proposed as alternatives.

[Vous devez être inscrit et connecté pour voir ce lien], in charge of Lockheed's secret [Vous devez être inscrit et connecté pour voir ce lien] that had built the A-12, developed the concept of a long-range drone that used much of the technology as the A-12 In October 1962, the CIA and the [Vous devez être inscrit et connecté pour voir ce lien] instructed Lockheed to study a high-speed, high-altitude drone concept.

Kelly Johnson specified speeds of Mach 3.3–3.5, an operational altitude of 87,000–95,000 feet (27,000–29,000 m) and a range of 3,000 [Vous devez être inscrit et connecté pour voir ce lien] (5,600 [Vous devez être inscrit et connecté pour voir ce lien]; 3,500 [Vous devez être inscrit et connecté pour voir ce lien]).

It was intended to make a one-way trip and eject its camera payload at the end of the mission for recovery before self-destructing.


^{[Vous devez être inscrit et connecté pour voir ce lien]} The Q-12 had a double-delta wing similar to the A-12's wing design.

The Q-12 was to be air-launched from the back of an A-12, and used key technology from the A-12 project, including [Vous devez être inscrit et connecté pour voir ce lien] construction and employed similar measures to reduce its [Vous devez être inscrit et connecté pour voir ce lien].^{[Vous devez être inscrit et connecté pour voir ce lien]}

Le bal des débutantes...

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Kelly Johnson wanted to power the Q-12 with a [Vous devez être inscrit et connecté pour voir ce lien] engine built by [Vous devez être inscrit et connecté pour voir ce lien] for the [Vous devez être inscrit et connecté pour voir ce lien] long-range [Vous devez être inscrit et connecté pour voir ce lien].

Marquardt and Lockheed had already collaborated on several programs and had a close working relationship.

The engine, the RJ43-MA-11, could be be used, but it needed a lot of work since it was only designed to burn as long as a BOMARC needed to hit a target.
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In contrast, the Q-12's engine needed to operate for at least an hour and a half and operate at high altitudes.

These conditions required extensive modifications to allow the engine to work at the high temperatures and low pressures of the Q-12's flight profile.

The modified engine was designated as the RJ43-MA20S-4.

A full-scale mockup of the Q-12 was ready by 7 December 1962 and had already undergone preliminary tests to measure its radar cross-section. Marquardt had also successfully tested the modified RJ-43 in its [Vous devez être inscrit et connecté pour voir ce lien] in the meantime.


^{[Vous devez être inscrit et connecté pour voir ce lien]} However, the CIA was not enthusiastic about the Q-12, mostly because the agency was overextended at the time with U-2 missions, getting the A-12 up to speed, and covert operations in Southeast Asia.

In contrast, the Air Force was interested in the Q-12 as both a reconnaissance platform and a cruise missile, and the CIA finally decided to work with the USAF to develop the new drone.

Lockheed was awarded a contract in March 1963 for full-scale development of the Q-12.^{[Vous devez être inscrit et connecté pour voir ce lien]}

The [Vous devez être inscrit et connecté pour voir ce lien], its [Vous devez être inscrit et connecté pour voir ce lien], and [Vous devez être inscrit et connecté pour voir ce lien] were carried in a cramped "Q-bay" below the drone's air [Vous devez être inscrit et connecté pour voir ce lien].

These systems were built into a module that fit into the bay and was known as a "hatch".

The hatch would be ejected at the end of the mission and it would be snagged out of the air by a J[Vous devez être inscrit et connecté pour voir ce lien], a technique that had been developed by the Air Force to recover film canisters from satellites.

If the C-130 missed, the hatch was equipped with flotation devices so it could be recovered by ship.

JC-130

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[Vous devez être inscrit et connecté pour voir ce lien] built the [Vous devez être inscrit et connecté pour voir ce lien] systems and new construction techniques and materials had to be developed to withstand the high temperatures, extreme vibrations and lack of space in the D-21.

The [Vous devez être inscrit et connecté pour voir ce lien]-coated wires proved to be very brittle and tended to break when the connectors were seated or if the pins moved.

Despite these advanced techniques and materials the actual instruments were fairly primitive.

One Lockheed assessment of the avionics said that they used "outdated 1940s-era electro-mechanical relays, technology and hardware that were not compatible with speeds in excess of Mach 3.3 at or above 90,000 feet (27,000 m)"

In late 1963, the project was named "Tagboard"; the Q-12 was re-designated D-21 while the A-12 version became M-21 (D- for "daughter" and M- for "mother").

Two of the original 18 A-12 aircraft were designated as M-21s, serial numbers 60-6940, and -6941.


The M-21 was a two-seat version of the A-12, with a pylon on the fuselage centerline between the [Vous devez être inscrit et connecté pour voir ce lien] to carry the drone in a nose-up attitude.[Vous devez être inscrit et connecté pour voir ce lien]

Operational history

Testing

The M-21/D-21 combination began captive flight-testing on 22 December 1964. [Vous devez être inscrit et connecté pour voir ce lien] covers were initially placed over the intake and exhaust to reduce [Vous devez être inscrit et connecté pour voir ce lien], but had to be removed after the first few tests, as a method of discarding them at Mach 3 without damaging the M-21 and/or D-21 could not be devised.<sup>[Vous devez être inscrit et connecté pour voir ce lien]

[Vous devez être inscrit et connecté pour voir ce lien]</sup>"The first launch of the D-21 from the back of the M-21 occurred successfully on 5 March 1966.

The release was successful, though the drone hovered above the back of the M-21 for a few seconds, which seemed to one of the flight crew like "two hours".