Author Topic: LHX - Light Helicopter Experimental pt1  (Read 4076 times)

Offline KiwiZac

  • The Modeller Formerly Known As K5054NZ
LHX - Light Helicopter Experimental pt1
« on: March 16, 2015, 09:58:21 AM »
The Light Family of Helicopters, Experimental (LHX) Programme was the largest such effort in helicopter history. Begun in 1982, every manufacturer in the United States entered designs for the competition, which sought to replace four existing types in the US Army inventory: Bell’s UH-1, AH-1 and OH-58, and the Hughes OH-6. A contract for as many as 6000 aircraft in two versions was on the line. The Scout/Attack (SCAT) variant to operate alongside the AH-64 Apache was the primary focus, with a utility transport (UTIL) also sought which was intended to use the same dynamic systems.

However it was very soon decided the UTIL would exceed weight and costing requirements and was put on hold in favour of SCAT alone. UTIL was eventually cancelled outright and more Sikorsky UH-60 Black Hawks were ordered to fulfil the role. Thus the LHX acronym was repurposed as Light Helicopter Experimental.

Formal proposals were submitted and reviewed in mid-1984, whittling down the field considerably. Boeing and Sikorsky allied for LHX-SCAT under the name “FirstTeam”, reflected by Hughes and Bell (historically rivals for Army helicopter contracts) who partnered as the “SuperTeam”. Lockheed submitted a solo effort, as did McDonnell-Douglas and Northrop. On July 4 1985 the Army announced the SuperTeam and FirstTeam designs to be the frontrunners and thus winners of Phase I – Phase II consisting of building two prototypes each, followed by a competitive fly-off (Phase III) to be held before 1990 to determine the choice of LHX.



The logos of the respective design partners

One of the key requirements of LHX was that of achieving a low-observable or “stealth” aircraft to allow the LHX to approach Soviet tanks undetected, marking targets for Apaches or even making its own attacks. The two teams went about this in different ways – Boeing-Sikorsky arrived at a faceted design (coincidentally like that of the then-unrevealed A-11 Nighthawk) with a fan-in-fin tail rotor which shrouded the radar-reflecting blades, and a T-tail. Hughes’ experience with its patented No Tail Rotor (NOTAR) system saw that facility integrated in its design with Bell, along with a more rounded airframe reminiscent of the SR-71 Blackbird, and a cruciform tail unit. Boeing-Sikorsky seemed to have an edge as its design used retractable wings for its weapons, whereas the SuperTeam LHX had fixed wings which were thought by some to create a larger radar return. Hughes-Bell emphasised the NOTAR system would even out this apparent anomaly.

Six months after the Phase I announcement Bell sold the rights to its four-blade composite rotor system - said by many to have been the former company’s sole contribution to the project - to Hughes Helicopters, and thus Hughes became the sole contractor. Accordingly the SuperTeam moniker was dropped in favour of simply “Hughes LHX”.


The logo adopted by Hughes' LHX team once Bell withdrew from the project

The race was now on. Initial mock-ups were built and displayed at airshows around the world, and experimental designations were assigned by the Army for development and test-flying – the Boeing-Sikorsky machine officially became the YAH-66, and the Hughes type the YAH-69. Commentators hung more descriptive names on the designs: the “Rough Diamond” and the “Sky Shark” respectively, based on their contrasting shapes.


FirstTeam's faceted YAH-66 design featured a FANTAIL tail rotor and five-blade main rotor

The Hughes team had the advantage of producing the AH-64 Apache, the Army’s chief attack helicopter which was proving popular with Army crews at the time. Lessons learnt from the Apache programme were put into the YAH-69 and in late 1986 the Army – and media – was told to expect a major event before the year was out, “a Christmas gift” as senior Hughes VP Noah Peterson said in November.

The prototype YAH-69, 85-18872, was rolled out at Hughes Airport in Culver City on the morning of December 22, and surprised guests by flying a circuit of the field – Hughes later revealing that flight testing had been ongoing since mid-November. The ensuing press exposure of the surprise flight meant the Boeing-Sikorsky team – whose “FirstTeam” collaborative name now became an embarrassment – had to redouble their efforts to catch up. The first YAH-66 prototype (s/n 85-18970) didn’t fly until March 12 1987, Hughes having flown hundreds of invaluable development hours by then. The second YAH-69, 85-18873, flew on March 18 and the second YAH-66, 85-18971, on April 2, at which point the US Army declared Phase II complete.


Hughes' sleek YAH-66 was the first LHX competitor to fly, its NOTAR system making it noticeably quieter than other machines

Phase III began when all four aircraft were airlifted in a C-5 to the Yuma Proving Ground for the fly-off in the summer of 1987, six weeks of test- and simulated in-service flying followed by a contract being awarded within three months. At Yuma on June 12, the first day of the fly-off, the US Army publicly announced new designations for the two hopefuls which reflected the new reconnaissance-and-attack role they would fulfil: the RAH-66 and RAH-69.

Speaking to press after the announcement, officials stressed that the time difference between the first flights of the YAH-66 and YAH-69 would have no impact on the Army’s ultimate decision and that Phase III was the only element of the programme that would affect this.

Although the actual flying was strictly off limits to media – “for safety reasons” claimed the Army, although industry commentators speculated it was to prevent industrial or Soviet espionage – cameras and reporters were frequently seen at the boundary fence waiting for the aircraft. Such was the public interest that model kits of the two aircraft (based purely on the now-outdated mock-ups and photographs) began appearing on shelves and vanished just as quickly thanks to high demand.

On July 28 85-18872 and 85-18971 were flown for the public at Yuma in a final display of their capability. This time the media was allowed to film and photograph from the base itself, and images of the two aircraft trying to outfly one another headed up evening news shows across the USA. Officials were tight-lipped but – as predicted by many – the Hughes aircraft seemed to be the front-runner.
After the demonstration the two display aircraft were handed over to the Army – the other two machines returning to their respective manufacturers – and promptly taken into storage for the remainder of the (now closed-door) evaluation.

Two months later the Army issued a release stating a press conference at Fort Rucker, Alabama – spiritual home of the US Army’s aviation corps, as well as location of its aviation museum – would be held to announce the winning LHX design, which had been transported to the base.

On September 30, 1987 the heads of Boeing, Hughes and Sikorsky were present at Fort Rucker along with a mass of media and invited guests to hear the LHX announcement. As the Army band struck up the National Anthem the Chief of Staff of the Army, General John A Wickham Jr, ordered the hangar doors open to reveal a tug – escorted by 12 soldiers in dress uniform – which pulled the YAH-69 prototype 85-18872 from the hangar amid cheers from the Hughes representatives. Gen Wickham announced a contract of 2,500 RAH-69s was to be awarded to Hughes – a contract worth close to $30billion – and that the aircraft would receive the name Navajo (the name Comanche would have been allocated to the RAH-66).

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In the real world was never really a fan of the Comanche but I was still unimpressed with its axing. I got to researching LHX and fell in love with the sleek SuperTeam design, so I thought I'd like to build it. It's from writing that backstory that I decided to do an earlier Comanche as well. So the RAH-69 Navajo WILL follow the YAH-66 - along with its backstory, already written - once I find suitable donor kits.

In the meantime I found Revell released a Snap-Tite Comanche model seemingly based on photos of the mockup. Crude, inaccurate, simple. PERFECT for bashing a prototype! So I got one cheap from Australia.


So far I've cut off the nose and tail, and cut off part of the engine cowlings (lovely deep panel lines helped immensely) to be re-built from plasticard. The FANTAIL will lose its distinctive angles and go back on straight. The gun turret will also be moved back, more in line with photos of sales models online.

Good times!! More progress this weekend.
« Last Edit: March 16, 2015, 10:00:36 AM by KiwiZac »
Zac in NZ
#avgeek, modelbuilder, photographer, writer. Callsign: "HANDBAG"
https://linktr.ee/zacyates

Offline LemonJello

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Re: LHX - Light Helicopter Experimental pt1
« Reply #1 on: March 16, 2015, 11:25:14 PM »
I'll be following this one with great interest.  Looks like you're off to a good start.

Offline KiwiZac

  • The Modeller Formerly Known As K5054NZ
Re: LHX - Light Helicopter Experimental pt1
« Reply #2 on: March 17, 2015, 06:16:32 AM »
It's fun but luckily - tempting fate - because it's faceted I don't foresee many issues with building new bits and pieces. I'm looking forward to doing more on it this weekend.
Zac in NZ
#avgeek, modelbuilder, photographer, writer. Callsign: "HANDBAG"
https://linktr.ee/zacyates

Offline Brian da Basher

  • He has an unnatural attraction to Spats...and a growing fascination with airships!
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Re: LHX - Light Helicopter Experimental pt1
« Reply #3 on: March 24, 2015, 06:59:28 AM »
You're off to a wizard start there, Zac!

Those logo designs look like they'll fit your chopper to a T.

Brian da Basher

Offline KiwiZac

  • The Modeller Formerly Known As K5054NZ
Re: LHX - Light Helicopter Experimental pt1
« Reply #4 on: April 12, 2015, 01:18:43 PM »
Finally a new photo or two! Round 1 of PSR complete, round 2 initiated. It'll be a few weeks until this is done, I fear, but I'm keen to do the best I can. I also need to start thinking about the new, longer nose.


« Last Edit: April 12, 2015, 01:28:33 PM by KiwiZac »
Zac in NZ
#avgeek, modelbuilder, photographer, writer. Callsign: "HANDBAG"
https://linktr.ee/zacyates