Posted : Monday Jun 28, 2010
CAMP BASTION, Afghanistan — In answer to criticism calling the Osprey vulnerable to enemy attack and lacking fire power, the Marine Corps shipped a handful of 7.62mm belly guns to Afghanistan last winter.
But the remotely operated turret guns, designed to give the aircraft a more effective way to neutralize enemy threats, has gone widely unused because Marines and their leaders believe its drawbacks frequently outweigh its benefits.
Marine Medium Tiltrotor Squadron 261, out of Marine Corps Air Station New River, N.C., has five belly gun systems with it downrange, but it is seen as heavy and difficult to use. A Marine crew chief, frequently a gunnery sergeant, operates the system from the inside using a controller and can rotate the gun 360 degrees. He acquires targets using a monitor that is fed color images from a forward-looking infrared sensor.
Marines, however, acknowledged that operating the belly gun system can cause nausea for the crew chief using it, since he must stare at the screen while the aircraft maneuvers.
Another major drawback is that the belly gun is heavy, weighing in at 800 pounds. That dramatically affects how much cargo or troops an MV-22 can carry. The Osprey can carry about 12,000 pounds of fuel, personnel and equipment in 70-degree weather, but when the temperature exceeds 107 degrees — as the summer weather in southern Afghanistan does regularly — the Osprey’s capacity drops to between 8,000 and 8,500 pounds, Woods said.
Lt. Col. Ivan Thomas, VMM-261’s commander, has told the media that the rules of engagement pose another challenge. Last summer, Army Gen. Stanley McChrystal, then the commander of NATO forces in Afghanistan, issued new guidelines directing commanders to restrict air-to-ground munitions and direct fire against residences. Thomas has said the risk of civilian casualties often is just too great to use the weapon system.
The belly gun was pushed out quickly based on an urgent need from the field for an all-quadrant defensive weapon system, but the mission-based system was never meant to be a permanent solution, Welding said.
Despite its drawbacks, pilots with VMM-261 say the 7.62mm weapon, formally known as the Interim Defense Weapon System, has impressed them with its accuracy and ability to lock onto targets while Ospreys are in flight. They are more comfortable though, using the Osprey’s tilt-rotor design to zip in and out of combat situations quickly.
“They gave it to us to work with, and it’s a phenomenal weapon,” said Capt. Brandon Woods, who has flown the Osprey since 2006. “But from our standpoint, it’s still easier to transition the aircraft to airplane and use our speed.”
The Ospreys in Afghanistan are also equipped with either a 7.62mm M240 machine gun or a .50-caliber machine gun on the rear door. Marines pick a weapon based on the perceived threat for each mission they undertake.
“The IDWS … is not intended to be carried on every flight,” said Maj. Brian McAvoy, the MV-22 plans and policies officer at the Pentagon. “In most instances during day-to-day assault support operations, the primary mission is to carry troops and cargo from place to place, and in these instances, the ramp gun provides adequate defensive fire suppression. What the IDWS does provide, when the commander needs it or wants it, is a crew-served, all-aspect, enhanced defensive suppressive fire capability that can be used in concert with the ramp gun.”
Navy and Marine Corps officials are working with BAE to monitor data gathered from the field, which will be used to determine what the long-term solution will be, Welding said.
The aircraft has been used frequently to ferry troops around Helmand province. It also has been used to insert troops during combat operations as well as longer missions to near the Pakistani border to the south and the Iranian border to the west.
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| A 7.62mm belly-mounted turret gun, known as the Interim Defense Weapon System. |
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| U.S. Marine Sgt. Danny L. Herrman, a flight line crew chief with Marine Medium Tiltrotor Squadron-263, test fires a 240 Gulf heavy machine gun on the back of a MV-22B Osprey while flying on a mission over the Al Anbar Province of Iraq. U.S. Marine Corps photo by Cpl. Sheila M. Brooks (Released) |