The old thread on this topic disappeard, so lets start a new one.

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AH-1Z Flies With “Stealthy” Exhaust

(Source: US Naval Air Systems Command; issued June 17, 2004)

NAVAIR PATUXENT RIVER, MD --- A major survivability upgrade to the AH-1Z/UH-1Y aircraft, currently in the latter stages of developmental flight test here, made its first flights this week at the Bell Helicopter XworX facility in Texas.

The upgrade, consisting of an integrated engine exhaust management system that then turns the hot exhaust gases out and away from the aircraft's tail boom, quickly followed Monday's ground run accomplishment by expanding the flight envelope from hover to 120 knots Tuesday.

"The flight consisted of a six-minute hover," explained Marine Lt. Colonel David J. Anderson, the H-1 program's assistant program manager for Systems Engineering, "followed by an over-night teardown and inspection. Tuesday, after the Bell team put everything back together, we took it up to 120 knots."

Bell's Advance Programs unit has been exploring ways to improve survivability of the Cobra for several years, developing a solution by managing the exhaust flow and integrating off-the-shelf components, then turning the exhaust away from the helicopter's tail boom.

"This is the culmination of over a year of design integration effort by a team of dedicated professionals," said Tom Mast, a Bell design engineer on the program. "Not only will it further decrease the helicopter's infrared signature, but engineers expect it will help with decreasing engine exhaust heat on AH-1Z and UH-1Y tail booms and reducing engine compartment temperatures. The upgraded T-700 engines require more advanced engine exhaust management than the older, less powerful ones. Finally, the system permits the engine to perform more efficiently, burning less fuel for the same amount of power."

The upgrade, which will also be applied to currently fielded AH-1W Super Cobras, many of which are supporting Marine Corps operations in Iraq, Afghanistan and the Horn of Africa, is the first major engineering prototype effort for Bell's XworX to benefit the H-1 program. Flight testing of the turned exhaust modification on the AH-1W Super Cobra is scheduled to begin in October with fielding in March 2005.

"Performance of the new turned exhaust over the past two days confirms what we hoped we would see," Anderson said. "Bell Advanced Programs and XworX are living up to our expectations - they're cutting their teeth on the AH-1Z and so far, we like what we see."

As originally configured, exhaust gases flowing over the tail boom made for a larger IR signature in both the AH-1W and the upgraded AH-1Z and UH-1Y. Because of greater heat coming out of the up-rated engines in the AH-1Z and UH-1Y, the exhaust heat also started affecting the structure of the tail boom itself. Advanced non-destructive inspection technology enabled NAVAIR engineers to understand the problems caused by the heating before they became safety of flight issues.

"We developed this innovative modification to save lives and reduce support costs," said Kendall Goodman, Bell's engineering team leader.

XworX engineers, working with their NAVAIR counterparts, fabricated and installed the parts for the turned exhaust modification. Complete flight test envelope expansion flights for both the AH-1Z and UH-1Y will continue at NAS Pax River.

"We were going to do this all along to gain additional survivability," explained Marine Col. Doug Isleib, H-1 program manager here, "but we found that what works for IR signature reduction also works to lower tail boom temperatures - making turned exhaust the optimal solution to both concerns."

The H-1 Upgrades Integrated Test Team here currently has achieved approximately 1,800 flight test hours with five aircraft (three AH-1Z and two UH-1Y test aircraft, of which all but one AH-1Z are production representative). The test aircraft have flown 222 knots, maneuvered from -0.4 to +3.5 g's, been well above the 10,000-foot altitude mark and recently completed their second operational assessment by Fleet pilots. The report from that assessment is pending.

With the turned exhaust-equipped AH-1Z returned to a flight status, XWorX artisans are now turning their attention to performing the same modification on the 84 percent identical UH-1Y. Flight test on that Y-Model Huey will resume once the modification is completed.

headers to squeeze out alittle mo HP

I know the article said "turned" exhaust but something in the ole BHG keeps translateing it to "tuned" exhaust

Shame about loosing some of the ole threads, crap is all I can say....

Volfandt

How about some pictures ma' bruthas...

DEVIL'S UPGRADE: Marine Corps' AH-1 Cobra Undergoes Some Hardcore Changes
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Living in the 80's? Not anymore! Improved radar, a helmet-mounted display system, increased payload and performance: Welcome the newest chapter in the AH-1 Cobra-USMC story. The AH-1Z Super Cobra era is about to begin.

The AH-1Z, or "Zulu," is essentially a technology upgrade to the Corps' existing fleet of 180 AH-1Ws. (Image from USMC Website).

AH-1 Cobra : The Skinny

Name:
AH-1 Cobra

Type of Equipment:
Attack Helcopter

Killer Features:
One 20MM turreted cannon with 750 rounds
Capable of carrying numerous 7 and 19 shot 70mm Hydra rocket pods
16 anti-tank guided missiles (ATGM) consisting of either the 3.5km wire-guided Raytheon BGM-71 TOW missile or the 8km semi-active laser homing Lockheed Martin AGM-114 Hellfire

The AH-1 Cobra series attack helicopter has been in service with the United States Marine Corps since the 80's. (ahem, since the 70's there chief )
The newest chapter in the Cobra-USMC story is the AH-1Z Super Cobra which is expected to enter operational service in 2007. The "Zulu" is essentially a technology upgrade to the Corps' existing fleet of 180 AH-1Ws. Once completed, the rebuild-and-upgrade program will add an additional 10,000 flight hours to the existing AH-1W airframes.

The two most significant upgrades to the AH-1 are also the two most obvious. Gone are the teetering, semi-ridged two-bladed rotors. Instead, the AH-1Z will have a four-bladed, hinge-less, bearing-less rotor system. Coupled to a pair of General Electric T700-GE-401 turbo shaft engines producing a total of 3,380 shaft horsepower, the four-bladed Zulu will have nearly double the Whiskey's payload as well as improved performance and endurance.

The second most obvious upgrade to the AH-1 is the nose mounted Target Sight System (TSS.) Built by Lockheed-Martin, the TSS incorporates an eye-safe laser rangefinder/target designator, an advanced third generation 3-5 micron-staring array Forward Looking Infra Red (FLIR) camera, and CCD TV. The TSS will allow the AH1-Z crew to automatically scan, acquire, designate and engage targets.

The AH-1 Cobra

As part of an overall plan to reduce crew-training needs as well as streamline crew efficiency the crew stations in the AH-1Z are all but identical, which not only facilitates maintenance, but also eliminates the need for crewmembers to undergo "front seat/ back seat" station training. The newly designed "glass" cockpits incorporate numerous multi function color data displays, a moving map digital navigation system and the Hands On Collective and Stick (HOCAS) system integration architecture, which allows the crew to access many of the helicopter's systems without having to take their eyes off of the target. In addition, the crew will be equipped with the Thales Avionics' TopOwl helmet-mounted display system. The TopOwl is a helmet-mounted sight that slaves the aircraft's TSS to the wearer's head movement (increasing situational awareness as well as improving target acquisition and engagement times.) The TopOwl is FLIR capable. It is equipped with a Gen IV passive night vision system and can switch between day-night optics instantly.

The Z model also incorporates a number of improved self-defense features. Topping the list is the new Lockheed Martin AN/APR-39(XE2) radar warning receiver, which can detect both continuous wave and Doppler type radar signals. An ATK AN/AAR-47 missile warning system provides missile launch warnings to the crew through the use of infrared detectors that detect the missile's hot exhaust plume. To alert the crew to laser designators or directed energy threats, the AH-1Z has a Goodrich AN/AVR-2A laser warning receiver. To defend themselves, the AH-1Z is equipped with both an active IR jamming system, the AN/ALQ-144A developed by BAE Systems, and an automated flare/chaff dispensing system, the BAE AN/ALE-39 chaff and infrared flare dispenser.

The increased payload and performance of the Zulu means that it's weapons load has been increased significantly. The Zulu can carry 16 anti-tank guided missiles (ATGM) consisting of either the 3.5km wire-guided Raytheon BGM-71 TOW missile or the 8km semi-active laser homing Lockheed Martin AGM-114 Hellfire. Longbow International (a joint venture between Lockheed Martin and Northrop Grumman) is developing the Cobra Radar System for the Zulu. Based on the mast-mounted millimeter wave radar used on the AH-64 Longbow Apache, the CRS will be a pod based, weapon station mounted radar that will enable the AH-1Z to fire the radar guided variant of the Hellfire. In addition, the Z is being certified for use of the AGM-65 Maverick missile, which will allow it to attack high value hard (armored) targets, such as bunkers or bridges. In addition to missiles, the AH-1Z will be capable of carrying numerous 7 and 19 shot 70mm Hydra rocket pods, as well as the larger 127mm Zuni rockets. To meet air to air threats, the AH-1Z can carry the AIM-9 sidewinder short range IR guided anti-air missile, and for air defense suppression the "Z" can also carry the AIM-9 based SIDARM anti-radiation homing missile, which locks onto threat radar transmitters and destroys them. Finally, the AH-1Z will continue to use the Cobra's 3 barreled, nose mounted, 20mm rotary cannon with 750 rounds of ammunition.


The AH-1 Cobra series attack helicopter has been in service with the United States Marine Corps since the 80's. (What again, I SAID since the 70's there chief!)

The AH-1Z reflects the Marine Corps' tradition for frugal effectiveness. Not blessed with the budget to develop expensive end-item systems such as the M1 Tank, the Apache helicopter, or the A/V-8 Harrier, the Marines have become very adept at working with what they have and making it better. The AH-1Z is a good example of this philosophy. The Cobra is a proven design, and while it may not have the speed or the armor protection of the Apache, it also does not have its price tag. This is not to say that the AH-1Z is a slouch by any means. With the ability to fire any ATGM in the US inventory, in addition to carrying both anti-air and anti-radiation missiles, the AH-1Z is fully capable of meeting all of the Marine Corps battlefield ground support needs for the foreseeable future.

quote:

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The AH-1 Cobra series attack helicopter has been in service with the United States Marine Corps since the 80's.

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Actually, since 1969. VMO-2 (Apr-Dec 69) and HML-367 (Dec 69-Jun 71) flew Gs in Vietnam.

I think they meant the W has been in service since the 80s.

Leo - awesome pic!

Volf - awesome article!

Thanks for posting them.

Weapons firing problem interrupts AH-1Z tests

Flight International
03 Aug 2004

Hot rocket exhaust ingested into engines curtails exercise after power surge

The US Navy has halted the final phase of weapons testing with the Bell AH-1Z Super Cobra while it studies whether to introduce a firing envelope restriction following a serious problem that occurred during a 22 July live fire test.

An AH-1Z was firing single 2.75in (70mm) rockets simultaneously from pods on both sides of the aircraft when the glitch occurred. Twelve pairs of rockets were supposed to have been fired in a salvo, but a pocket of hot rocket exhaust not dispersed by the Super Cobra's rotor downwash was ingested into the helicopter's engines after only three or four rockets had been launched.

The heated air caused the engine power to surge, over-stressing the helicopter's drive train. The test team ordered the pilot to land the aircraft.

Programme engineers are now studying a range of options to avoid the problem from arising in the future, including possibly restricting the envelope for weapons firing. The current pause on weapons testing is not expected to delay the USMarine Corps' overall schedule, which covers the remanufacture of 100 AH-1Ws into AH-1Zs and 180 UH-1N Huey utility helicopters into UH-1Ys for the US Marine Corps.

The over-torque issue is the second major glitch reported by navy officials as the AH-1Z programme advances toward an operational evaluation phase scheduled to start next February. Programme development stopped for three weeks from early February 2004 to address a tailboom annealing problem caused by hot exhaust from the engines.

The problem has been solved by installing a "turn kit" that re-directs the exhaust outboard, rather than directly on to the boom. Bell is being awarded a $7.2 million contract to supply the first 24 turned exhaust kits by December 2005.

The design change also is expected to reduce infrared signature, improving survivability from heat-seeking missiles.

STEPHEN TRIMBLE / WASHINGTON DC

Dear Sgt_Schlappy,

HIthere!Wow,your photos with the information on the Cobra is Outstanding!Hey do you have the mailing address for the Huey-Cobra Squadron military mailing address for IRAQ?They leave tomorrow morning for 7months....Do you know a website I can go to in order 2 recieve updates ?Anything you can do/tell me to help me keep my sanity would be deeply appreciated...

sincerely , kellie

Which Squadron GYSGTOCHOAWMN ???

The V-22 Integrated Test Team shared a hangar with the Y/Z upgrade team up at Pax River. It was hard to get used to the new rotor noise of the 4 bladed variants like that. They've lost that old familiar "whop-whop" due to the added blades and "headers" and now sound like a miniature 53 when they are out punching holes in the sky
Now that we are back at New River, I sort of miss that unique noise......

If someone would be good enough to educate me how to post pictures here, I would be happy to post shots of Z-1 with the turned exhaust. I also heve shots of Y-1 doing rocket accuracy testing at Fort A. P. Hill. Thanks.

hinklejd, the jpg's have to be hosted on a web server that can be linked to.
You cannot link a jpg from your hard-drive unless it has a static IP address and is always on line, like a web server is.
There are many web servers that offer free hosting space but they seem to change and I'm not up on them. Perhaps someone that utilizes one will post it.
Many ISP's offer web space along with the package you get when you utilize their services, you may check and see if this is available for you.

Volfandt

Here's a host that I have had luck with on posting photo's with, I just up load them, copy the address of the photo and then hit the image button at the bottom of the post a reply ( where it says UBBCode) and they come up. You may have to play with a little while to see how it works ( the great thing about this is, it won't stunt your growth), like I did.

http://www.photobucket.com/

I've seen the new exhaust upgrade, and its different thats for sure.

AH-1Z/UH-1Y Pass 2,500 Flight Hours

(Source: Bell Helicopter; issued Jan. 19, 2005)

NAVAIR PATUXENT RIVER, MD --- The H-1 Upgrades program here achieved yet another major testing milestone recently with the achievement of 2,500 mishap-free flight-test hours for the upgraded UH-1Y and AH-1Z.

Coming as the program is rapidly bringing the system development and demonstration phase to close and preparing for the "graduation exercise" of operational evaluation this summer, the milestone reflects the success of the program to date and what's in store for the Fleet Marine Force.

"Proving their expanded capability to fight in extreme conditions like snow, cold and hot weather, high altitude, dust and desert, these aircraft are on track for a successful OpEval this summer and beginning of full-rate production," said Maj. Dave Thompson, the H-1 program's engineering and manufacturing development IPT military lead and a UH-1N pilot.

"The capabilities demonstrated by the aircraft are really exciting," he added. "Especially the UH-1Y - what a huge improvement over the UH-1N."

The program recently received positive feedback from an operational assessment by Fleet pilots and crews. Operational assessments provide more of a quick check during development. More definitive findings will be a part of this summer's operational evaluation.

Weapons testing in Arizona, meanwhile, included initial testing of the AH-1Z's ability to perform its primary mission - close air support. During the four-month weapons accuracy test, the aircraft fired nearly 800 Mk-66 2.75" rockets at air speeds ranging from 60 to 200 knots, five AGM-114 "Hellfire" anti-armor missiles, three AIM-9 "Sidewinder" air-to-air missiles and approximately 3,000 rounds of 20mm ammunition from its M-197 automatic gun.

The UH-1Y has successfully fired approximately 400 2.75-inch rockets, 12,800 rounds of machine gun ammunition, 136 flares, 104 chaff canisters and 104 decoys on nearly 40 test flights.

"This milestone is a direct result of the diligence exercised by the test team in its safe and deliberate execution of a solid test plan," said Lt. Col. David Anderson, H-1 assistant program manager for systems engineering. "Achieving 2,500 flight test hours in approximately four years shows us the inherent robustness of the platform and the program-wide professionalism behind the success."

After remanufacture, the H-1 Upgrades aircraft will feature the latest technology in rotor and drive train design, avionics, sensors and weapons. They also share approximately 84 percent of their parts, making them far more maintainable, supportable, survivable and deployable than today's H-1 aircraft.

"The Fleet's going to love these aircraft," Anderson said.

By 2014, the Marine Corps will have procured 100 UH-1Y Hueys and 180 AH-1Z Super Cobras.

If you are going to post a picture on the forums, make sure they are no bigger than 35Kb or 640X800MP. I had to delete the two pictures you posted because they were just to big. A lot of people here have dial-up modems and it takes forever to load the page up and it stretches the page to twice its width, when an abnormally large picture is posted. Thank you.

Bell backs bid to swap UH-1Y upgrade focus to new-build

Flight International
18 Jan 2005

But manufacturer says obtaining approval for SuperCobras will prove more difficult

Bell Helicopter is confident that the vast bulk of a US Marine Corps order for 100 upgraded UH-1Y Huey utility helicopters will be converted from remanufactured to new-build airframes this month, but says obtaining approval for about 40 of 180 upgraded AH-1Z SuperCobra attack helicopters is proving more difficult.

The company has already invested internally in non-recurring engineering work to launch a new-build UH-1Y production line in three years, converting 88 remanufacture aircraft into all-new airframes.

The USMC is unlikely to secure a commitment for its new-build UH-1Y acquisition strategy until later this month, when the US Department of Defense will reveal its budget request for fiscal year 2006. "If you look at the amount [of a UH-1N] we reuse it's 18% of the aircraft," says Kevin Connell, Bell's H-1 upgrade programme manager. "But when they take an aircraft out of the field to turn it into the remanufacturing cycle they are basically reducing the force structure until they get an aircraft back that they can use."

A different argument will be needed to attract support for converting to new-build AH-1Zs, which reuse about 60% of theAH-1W. Bell's marketing theme will focus on the likely attrition rate of the AH-1W fleet, which may cause airframe shortages during the remanufacturing process. "If you consider attrition today because of the war effort, [the new-build strategy] is something the customer absolutely needs to do to protect the force structure," says Connell. "What we are looking at is potentially 40 new-builds to be inserted somewhere in the Lot 4/Lot 5 aircraft timeframe so that we can minimise the number of aircraft that we pull out of the fleet."

Connell says the 40-aircraft proposal also would allow the USMC to sustain a minimum inventory of attack helicopters through 2020, assuming a 2% annual attrition rate.

The UH-1Y and AH-1Z are due to enter an operational evaluation phase in June. Both are on schedule to enter the testing period.

STEPHEN TRIMBLE / FORT WORTH

I was wondering how the war would affect the remanufacturing process. Still good to hear the H-1 program is going well. It would have been good to have the "Z" and "Y" models in Iraq. I'm almost more excited about the Huey once again flying the missions like it did long ago.

Well, they finally started the modification process changing the ole AH-1W to the new AH-1Z. Loaded the airframe in the jig last week and this week started drilling and mashing rivets. What a great sound! Building V-22's is an incredibly satisfying occupation, but there's just no feeling like a sheetmetal aircraft that can take a beating and come back asking for more.

FYI - Projected schedule shows the first flight testing sometime toward the end of the year, around November.