Martin COIN
Naval COIN aircraft
Counter-insurgency aircraft or COIN aircraft (Counter-insurgency aircraft) is now a specialized variety of military light attack aircraft , designed for counter-insurgency operations, armed reconnaissance , ground troops air escort and ground support "low-intensity combat"; usually an informal insurgency group equipped with aircraft cannons and/or portable rocket . The surging Third World anti-colonial movement around the world in the 1950s and 1960s gave birth to such a special category in the air force of capitalist countries.
AT-28D
used for COIN aircraft AT-28D
The US imperial began to intervene in Vietnam in the early 1960s, thus turning the anti-insurgency mission into the main task of naval air force. At first, the US Navy tried to use the North American T-28 trainer and the bulky A-1 attack aircraft to undertake such tasks. However, these non-professional aircraft are naturally difficult to adapt. The T-28 is too fragile, while the A-1 attack aircraft is not flexible enough, and it is too burdened with a single-person crew at ultra-low altitudes.
A-1
L2VMA
L2VMA solution provided by Colonel Rice
Last issue (
L2VMA concept model and A-1 attack aircraft size comparison
Then the Navy integrated the demand for COIN aircraft with the Marine Corps' L2VMA. Next, as Pentagon became more and more interested in this aircraft, the US Army and Air Force joined in, in 1963, various Required to be merged into the three armed forces specifications of the Light Armed Reconnaissance Plane (LARA).
L2VMA Demand Indicators
L2VMA Weapons
Martin COIN
Martin Company Booklet Cover
The protagonist of this issue was Martin. At that time, they had not merged with Lockheed. They were one of the LARA project 11 bidders. Martin had already met with the Navy as early as 1961 in the 1961st Navy's COIN aircraft stage. Touch. Therefore, even after the project has been renamed LARA, I still call my plan Martin COIN.
full-size model
The author of this model: allysonca
air blowing tail wing
Martin's plan is very similar to the concept of L2VMA, small, dual-engine, turboprop power, and double tail braces. There is a tandem dual cabin, with a small cargo hold at the rear, which can also be carried by people. In addition to the driver, the driver can carry up to 6 armed steps. Soldiers, or four stretchers and a medical staff, with a rectangular single wing, the engine compartment is located in the middle, and two United Airlines T-74 engines drive three-blade propellers. The tail beam extends from the rear of the engine.
three views and fuel tank layout
crew layout
airdrop cargo
airdrop cargo
The most obvious feature is the inverted V-shaped vertical tail. This vertical tail is not only a unique shape, but also has a unique function, using Martin Engineer Hans The patented technology developed by Multhopp, the engine exhaust will be blown to the surface of the inverted V vertical tail through a special conduit.
Hans Multhopp's patented air blown tail wing
The working principle of the tail wing
It is said that this layout can automatically correct the imbalance caused by single-shot faults in low-speed states. This performance is very important to COIN, because the Navy attaches great importance to short-range take-off and landing capabilities, especially when deck take-off and landing. The combat load take-off speed of Martin COIN is only 25 knots, and the maximum speed is 250 knots. Take-off and land The frame is a front three-point type, with large diameter front wheels and double rows of main wheels to adapt to the non-paved temporary runway. The front wheel is loaded forward into the nose of the machine, and the main wheel is folded backward in the engine compartment.
cockpit and structure
sectional view
combat take-off weight is 4027kg, and the take-off and run distance is only 135 meters. The weapon equipment is built-in four-studded 7.62mm M-60 machine gun, wingtip two mounts can mount the Rattlesnake missile, and three mounts under the fuselage can mount the common rocket and the conventional bomb .
Weapon system layout
According to the special needs of the Navy, COIN must be able to quickly transform into seaplane . Martin gave a double float plan.
Pilot boarding process
ending
Martin said COIN is fully competent for close-range support, patrol and reconnaissance, artillery observation, front-line transportation and other tasks. It has excellent short-range take-off and landing capabilities and excellent single-engine flight capabilities.
Martin COIN Full Size Model
Martin COIN's data are just right among competitors. Martin has built a full-size model and printed exquisite brochures. The unique air-blown tail wing is studied in NASA's wind tunnel. However, none of them were favored by the Navy, and the Navy finally chose the North American NA-300, which is the OV-10 North American Mustang.
NASA's research model data
NASA's research model data
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