Talk:AH-56 Cheyenne

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[edit] AH-56 or AH-56A?

Is this the AH-56 or the AH-56A, as it is listed in the external link? Rigadoun 19:55, 16 June 2006 (UTC)

This is the AH-56A following the Air Force designation system for aircraft. Technically, if there were to have been a family of AH-56 variants they would collectively have been known as the AH-56. I believe that this should be the AH-56A Cheyenne page and the 'AH-56 Cheyenne' should redirect here just as 'AH56 Cheyenne' does. However, it is a popular and accepted technique to leave the variant designation out when talking about a single instance of an aircraft. (Born2flie 23:12, 16 July 2006 (UTC))

[edit] XH-51 and AH-1G

My real issue on this page was that this aircraft was not designed to replace the AH-1G, but rather the AH-1G was selected as the interim aircraft until the AH-56A could be put into production and deployed to the Aviation units. This is evident from the dates of the programs and design periods. The AH-1 survived much longer than intended as an 'interim aircraft' (due to the cancellation of the AH-56A) much like the OH-58D survived much longer than intended as the 'interim aircraft' between the OH-58A and OH-58C variants and the LHX (later the RAH-66 Comanche).

Additionally, the XH-51 was actually Lockheed's CL-595 helicopter purchased by the Navy for a test program, commissioned by the Army, to study the survivability of helicopters based on the extra speed of compound helicopters. The study consisted of two CL-595's redesignated XH-51[1], both heavily instrumented. The XH-51A was simply instrumented, but the XH-51B was highly modified with stub wings. The left wing had a turbofan engine mounted on it and the right wing had a wingtip fuel tank to extend range, and the cockpit was reinforced to withstand the high speeds of the compound aircraft. The tests consisted of flying three circuits of three routes; 1. low, open terrain; 2. shallow hills; 3. mountainous; with motion cameras mounted in the helicopters and at likely anti-aircraft gun emplacement locations. The results showed that the significant speed advantage, while causing the aircraft to fly slightly higher, reduced the time available to detect, locate, and target the compound helicopter. Based on this study and the demonstrated performance capabilities of the XH-51B, the Army submitted the Request For Proposal for the Advanced Aerial Fire Support System (AAFSS).

Once I have my sources lined up, I plan on editing this page. --Born2flie 16:20, 15 July 2006 (UTC)

[edit] Abridged history of the Army Attack Helicopter program

I googled on the AAFSS and found this interesting study from 1973 [2]. I think it could be a great resource for this article. I just peeked into it... --Marvin talk 22:34, 22 July 2006 (UTC)

I think you've found a great reference. The article itself, being an official document, but then the bibliography is gold. Odd that this hasn't come up in my previous searches over the years. (Born2flie 18:33, 23 July 2006 (UTC))
I am glad that I can be of a help :) I searched on AAFSS A-X. --Marvin talk 00:26, 24 July 2006 (UTC)

I did numerous internet searches for that report and can not find an electronic copy. I searched on dtic.mil and googled *.mil sites and entire web using parts of that title with no luck. But it looks like Born's link 5 below is it. Don't know why file doesn't show up on a search.. -Fnlayson 04:16, 29 May 2007 (UTC)

[edit] Stub-class

I rated this article as a stub class due to incomplete information. (Born2flie 03:46, 11 September 2006 (UTC))

[edit] Copilot/Gunner Location

I think there is some confusion initiated by this article as to where the gunner's seat is located. The copilot/gunner is positioned in the front seat and the pilot is positioned in the rear seat like a typical American attack helicopter. If there is a dispute about this, I have photos of the front and rear seats (unsure of the copyright) and it is pretty evident which one is front and which one is rear. Not to mention that I've actually climbed on and into one of the copies at the Army Aviation Museum at Fort Rucker and can personally attest to the rotating gunner seat's location. (Born2flie 12:30, 15 November 2006 (UTC))

[edit] MANPAD

Around this time shoulder fired missiles were being deployed by many of the world's armies.[3]

– Lyta79

Born2flie: Around what time? The MANPAD missile (e.g. SA-7 Grail) is popularly touted as one of the reasons for the demise of the Cheyenne, but the official Army documentation blames the Army for painting an inexperienced helicopter manufacturer into a corner. The SA-7 didn't enter the theater until 1971-2, well after the Army had cancelled the production contract (1968) and just before the Congress cancelled the program entirely. The truth about the final cancellation is probably much closer to the Army becoming focused on a Fulda Gap scenario, and while the Cheyenne could be adapted to the tactics, the powers that be determined that, based on lessons learned from Vietnam (shootdowns by crew-served weapons), more survivability measures needed to be incorporated in the aircraft design. Interestingly enough, neither the UH-60 nor the AH-64 were developed with survivability designs to withstand Surface-to-air missiles (MANPADAS or otherwise). So, even with the reference, the statement remains unqualified because no direct correlation can be made to the introduction of the SA-7 into the Vietnam theater and the cancellation of the Cheyenne program in favor of the AAH. --05:00, 21 January 2007 (UTC)

[edit] death of the AH-56

See the this article at the centennial of flight website.[4] MANPADS did play a role in killing the AH-56. The inflation of the 70's did not help either. I wish I still had my "World Air Power Journal" books (lost them when I joined the army). Lyta79 05:51, 21 January 2007 (UTC)

Born2flie: I've seen and rejected that article as a reliable reference. See this reference.[5]. The Cheyenne died for the same reason the Comanche did. It took too long to develop because the Army kept changing the terms as they went along in order to get what they thought was the best possible solution. I also have VHS videos of Army doctrinal development for the AH-56, with the AH-1 standing in for the AH-56 in a Fulda Gap scenario (one that is well aware of the USSR's ADA threat). On page 9, of the reference I provided the link for, you will find this paragraph at the bottom of the page:

"On 14 January 1972, the Army established a special task force to conduct a reevaluation of its attack helicopter requirements and to prepare an updated and defensible Materiel Need (MN) document. In the generation of this MN, the Task Force considered field tests, combat experience and computer simulations that have been conducted over the past several years as well as actual flight evaluations of the CHEYENNE and two company-funded prototypes (Bell KING COBRA and Sikorsky BLACKHAWK). The requirements identified for an Advanced Attack Helicopter which could be available in the late 1970's described an aircraft that would be more agile, smaller, slower and less sophisticated than the CHEYENNE. This requirement also defined a less costly system than that of the original AAFSS requirement, Based on these results, the Secretary of the Army announced on 9 August 1972 the decision to terminate CHEYENNE."

So, the SA-7 did not come close to being a reason the AH-56 program was ended.

"During the Spring and Summer of 1971 LAC and the Army initiated a producibility/cost reduction (P/CR) study in an attempt to significantly reduce AAFSS costs. The then estimated procurement unit cost of $3.8 million was reduced by about $0.5 million through a variety of means. P/CR efforts continued up to cancellation of CHEYENNE."

Inflation did not play a part, since the producibility/cost reduction studies had reduced system cost to by almost $0.5 million. Consider that 4 years later, the AH-64 came off the line at close to $6-8 million per unit. These arguments about the demise of the AH-56 are much akin to the argument that Lady Byrd Johnson owned stock in Bell and that is why the OH-6 was replaced by the OH-58; Army aviation urban legend. --06:46, 21 January 2007 (UTC)

Why does the Redstone Arsenal's Historical Information web site's TOW MISSILE SYSTEM CHRONOLOGY [6] reference the SA-7 twice? The army's experience with the AH-1 in Vietnam, where the SA-7 was used, caused the Cheyenne to be killed off.

May 1972 The decision to deploy the 1st Combat Aerial TOW Team to the Pleiku/Kontum area near the Dak Poko River was based on two main considerations. The first was the 2nd Corps Tactical Zone’s (CTZ’s) critical need for an antitank system to counter the high probability of a large number of NVA armored vehicles in that sector. Another reason was the need to protect the XM26 TOW/HUEY helicopter assets from the SA-7 Grail antiaircraft missile system which the enemy had deployed in the 1st and 3rd CTZs.
...
9 August 1972 The Army terminated the CHEYENNE (AH-56A) program. The experiences of the airborne TOW teams in Vietnam played a role in this decision. With a combat-proven point weapon system, the Army was able to convince Congress to support the AAH program.[7]

Lyta79 08:05, 21 January 2007 (UTC)

Born2flie: Again, the reference I provided would tell you that the TOW was a designated CHEYENNE weapons development system until the production contract was cancelled and then it was designated a COBRA system. The CHEYENNE continued to remain in development until its cancellation, but you still haven't clearly drawn a line between the system's presence and the cancellation of the program. I would also mention that the second half of the document I'm referencing covers the earliest part of the AAH program. --12:02, 21 January 2007 (UTC)
Born2flie: I will also say that many of the published works that only mention this program cite other works that are only slightly less removed from the timeframe than themselves. Therefore, I find this reference to be highly accurate since it is closer in time to the actual events.
In regards to the TOW Missile system, apologies for remembering the chronology incorrectly and my reference. However, even that does not invalidate my arguments. 1968, the TOW system is designated for development of the AH-56. I've seen the test fire videos and demonstration video with the system mounted on the AH-56. It was fully functional on the airframe, therefore could not have been a valid reason for termination of the AH-56. After the AH-56 termination it is designated a COBRA program, not an AAH program. Why? Because the HELLFIRE program was already underway (1971) and this system would be developed for the AAH.[8] TOW? Not a factor.
Two other things are easily established to counter your arguments. The SA-7 (incorrectly listed as the SAM-7 in your reference) wasn't introduced until Spring of 1972 in the Vietnam theater. This is established by reports from AC-130/AC-119 crews over the Ho Chi Minh trail[9] and an actual report of an OH-6 being shot down that summer.[10] The AC-130 sources I've seen describe difficulty in establishing the missile system's presence as a fact to PACAF, therefore, until it was clearly established, it is likely that such a system would not have any real influence on programs that were currently being developed. Also, any tactics to counter the use of this threat system would not have been developed and used to influence system design (or continuation) until real world experience drove the tactics to be developed, which, based on the threat system's introduction would have occurred after the program had been cancelled and the next program established. And, while countermeasures had probably been in development since the introduction of the SA-7 into the Soviet arsenal in 1967, the CHEYENNE design and the requirements that had spawned the AAH, were created in absence of the influence of intelligence about this system.
The AAH Materiel Need (MN) document was produced in January 1972. Again, you offer no reference that this Materiel Need and its requirements were created based on the introduction of the SA-7 system into the theater. Why? Because the timeline cannot, in any way, support such a suggestion. The reasons we know that the Cheyenne did not meet the need was because it didn't have the survivability features (dual engine, redundant systems, crash attenuation) that were built into the AH-64 and UH-60. Your reference makes the claim that the AH-56 could not be down among the trees, but the CH-47 is an older, larger, heavier airframe that is made to do the same thing with two large rotors and for the same reason as your claim states. In addition, the Army had already created the concept of anti-tank doctrine and NOE tactics around the CHEYENNE, going so far as to use AH-1Gs, the "interim solution", as stand-ins for the Cheyenne (May 1971),[11] even as the concept was being validated in combat with the UH-1B TOW/HUEY program aircraft.
The AH-56 was designed to avoid being hit, the AH-64 was designed to absorb some hits, but neither aircraft was envisioned nor designed in reference to the SA-7. The current countermeasure for the threat is an add-on to the current Army airframes, just as it was back in those days. And the change in tactics is applied to large and small helicopters alike. Once again, the introduction of the SA-7 as a factor of the AH-56 program's cancellation is an unqualified statement; there is no proof that it is accurate based on an evaluation of both the timeline facts and the replacement program's design criteria. --17:11, 21 January 2007 (UTC)

Going by the Abridged History report, the AH-56 had several pending problems when it was canceled and that would probably drag out development and increase program costs. -Fnlayson 04:21, 29 May 2007 (UTC)

  • Fnlayson, that is the Production Contract. Keep in mind, the Army changed the performance requirements prior to finalizing the contract and this after awarding the contract based on Lockheed's design proposal. This caused major re-engineering of Lockheed's design after the fact of the contract being awarded. By the time Cheyenne was viable and cheap enough to afford, the Army was looking for a different solution. Compare with the Comanche that spent 20 years in development and has been in the works as the Advanced Scout Helicopter (ASH, later LHX) since the AAH was in development. --Born2flie 18:42, 8 June 2007 (UTC)

[edit] Developed from

It is really accurate to list the XH-51 in the "developed from" field? I understand the Cheyenne's rotors are basically scaled-up versions on those on the XH-51, and as such it certanly qualifies to be listed under the "related" field in the {{aircontent}} template. But other than the rotor systems, do they actually share any design features or components? Just asking. It's certianly not comparable with the AH-1 being developed from the UH-1, in my opinion. - BillCJ 04:17, 22 March 2007 (UTC)

It's the rigid rotor system design. There is a clear line from the CL-475 to the CL-595 to the CL-840 as far as the rotor system's development. Each aircraft, although none look alike, build on the developments in the rotor system before it. I believe that was Lockheed's focus, specializing in a new type of rotor system that allowed more stable helicopter handling. If the fiasco, that the Cheyenne program turned into, hadn't happened, helicopters today might have been easier to fly from the start, and the Lockheed 286 might have turned into a commercial success. --Born2flie 12:14, 22 March 2007 (UTC)

I certainly makes them related, and I agree the rotor system design is key to the whole concept Lockheed developed. But the AH-1G is basically a UH-1C with a different front end. Everything on the Cheyenne is different in airframe and design, save for the rotor system design. I'm not trying to be picky, as I considered putting the XH-51 in that field myself. Just asking for your justification, and you've given that. At this point, I know where you stand on it, and I won't be engaing in a revert war over it, or I would have just deleted it without discussion. I've done that enough to know it's usually best to ask you first! I accept that you have a valid reason (you usually do), and it's not worth pursing beyond that. - BillCJ 15:52, 22 March 2007 (UTC)

Bill, you don't have to defer to me. I won't have a real problem if you remove it and simply list the XH-51 in the Related development section. Either way is fine with me, but thanks for asking, I appreciate and understand your desire to avoid any conflict over it. --Born2flie 17:38, 22 March 2007 (UTC)

Hey, you fly helicopters, I READ about them - I know there's a difference! :) - BillCJ 18:32, 22 March 2007 (UTC)

[edit] WP Assessments

I don't believe this article currently covers the AH-56 well enough to meet the "reasonably covers the topic" criteria for B class rating. Is that how others see it or not? -Fnlayson 21:18, 1 October 2007 (UTC)

I agree with you, Jeff. Not even close to adequately covering the subject to be a B-Class article. I occasionally try to improve my sandbox version of this article. When I get it more organized, I'll invite you and Bill to help edit it. --Born2flie 21:36, 1 October 2007 (UTC)
  • Good. I didn't think there was anything seriously inaccurate with it. I'll be glad to help with your sandbox article when you're ready. -Fnlayson 21:41, 1 October 2007 (UTC)

[edit] Prototypes later use

OK, there were 8 prototypes left after cancellation of the program. I guess these just stored. Seems like they would try using them for flight test research or weapons fitting, something. Judging by what I've been able to find, any later use was minor or didn't happen. Is this correct? Thanks. -Fnlayson 15:17, 21 October 2007 (UTC)

Four prototypes have survived to be displays. One at Fort Campbell, KY, one at Fort Polk, LA, and two at the Army Aviation Museum at Fort Rucker, AL. I believe the rest were gunnery targets, I'm not sure what location. --Born2flie 00:30, 22 October 2007 (UTC)
  • Thanks. I need to go see to one and other helos at Fort Rucker. There might be some good pictures to take there. -Fnlayson 00:46, 22 October 2007 (UTC)
I would say that the Fort Polk aircraft is in the best shape, as it was recently restored in the 1990s. The Fort Rucker aircraft on display is in terrible shape and the one in storage is in a better condition but badly in need of a repaint. The Fort Campbell aircraft, the last I saw it, needs a lot of work. Pretty good, though, to have four displays of the aircraft that never made it into the inventory! --Born2flie 02:00, 22 October 2007 (UTC)
  • OK. Fort Campbell is the next closer one to me. I can't think of another aircraft where 10 prototypes were built of the same variant. Maybe I haven't paid a lot of attention to that. -Fnlayson 02:13, 22 October 2007 (UTC)

Each of the 10 prototypes was built for a particular task

1000, No serial Number, never flew, was simply a static test article, Aberdeen Proving Grounds as of 1982

1001, Ser 66-8826, Ground test vehicle, never flew, Used for various ground, engine and rotor tests, Used for ballistic survivability testing at Rock Island Arsenal, Was in state of dissasembly at Aberdeen proving grounds as of 1982

1002, Ser 66-8827, Flight Development Vehicle, Initial Flying qualities and areodynamics, 1st to fly, Fort Polk Display

1003, Ser 66-8828 Flight Development Vehicle, Envelope Expansion, Crashed, Killing Dave Beil

1004, Ser 66-8829 Weapons Integration Vehicle, Scrapped

1005, Ser 66-8830 Avionics Vehicle, 1st to have the full avionics (IHAS) Fort Rucker, Storage

1006, Ser 66-8831 Weapons Test Vehicle, Used in the Cheyenne / Cobra Flyoff at Hunter Ligget Fort Campbell Display

1007, Ser 66-8832 Missle and night Vision Vehicle, Fastest recorded flight of all prototypes 240 knots, Fort Rucker Display

1008, Ser 66-8833 Avionics Labrotory, never flew, Aberdeen Proving Grounds as of 1982

1009, Ser 66-8834 Flight Development Vehicle, replaced 1003 as the envelope expansion vehicle and was fitted with an F-104 Ejection seat in the front cockpit after the loss of 1003, scrapped

1010, Ser 66-8835 Complete Systems Vehicle, Destroyed in Ames wind tunnel —Preceding unsigned comment added by 74.166.21.69 (talk) 08:38, 5 January 2008 (UTC)

[edit] Dash speed

The AAFSS requirements were for a cruise speed of 195 knots with dash speed of 220 kt. What is the 212 knots dash speed mentioned in the article? The actual max speed it reached maybe. Thanks. -Fnlayson (talk) 18:40, 5 January 2008 (UTC)

I believe that 212 knots was listed by Jane's (I don't have access to my reference copy, but that is the reference I listed) and is probably the highest speed achieved during flight testing. --Born2flie (talk) 07:59, 6 January 2008 (UTC)
  • Thanks, that was my guess. I missed the Jane's reference for the specs. That'd be a good bit of info to add. "The Cheyenne reached a maximum speed of 212 knots during flight testing." or something along those lines. But I don't have a good reference handy. I'll see what I can find... -Fnlayson (talk) 16:55, 6 January 2008 (UTC)

According to Lockheed, 1007 reached a maximum speed of 240 knots during flight testing, the fastest of all of the prototypes that actually flew.

And since we're discussing dash speed, Allow me to better explain my opposition to the the original last sentence of the 1st paragraph. The sentence began by stating that the compound design was intended to produce a dash speed of 200+ knots and then stated that it was so that the cheyenne could escort tranport helicopters such as the Iroquois.

It seemed to me to be very much like saying that the police utilize interceptor type cars to deal with all the people driving Yugo's.

Additionally The speed requirement, according to the Abridged History of the Army Attack Helicopter Program, "Appeared to have been a combination of what was technically feasible and the rule of thumb (Pi/2 X [escorted vehicle cruise speed]" Utilizing this algorithm and the 212 knot dash speed, the escorted vehicle cruise speed would need to be around 140 knots which is of course in excess of the Iroquois' max speed

Lastly, should we not mention something about how a hybrid overcomes that which limits the speed of traditional helicopters, namely, retreating blade stall? —Preceding unsigned comment added by 74.166.21.69 (talk) 09:19, 19 January 2008 (UTC)

[edit] Cheyenne vid clip

FYI I have posted a clip which has a few seconds of the Cheyenne at low-level on LV:

http://www.livevideo.com/video/26958AF88B864CD4B154822DC09ACE0D/the-ill-fated-cheyenne-attack-.aspx

Fascinating plane. Good WP.

Royzee (talk) 16:55, 29 January 2008 (UTC)