Boeing Vertol alternate HLH proposals and other crane helicopters
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Boeing-Vertol C6041 Heavy Lift helicopter concept poster found on eBay.
URL:
http://www.ebay.com/itm/Boeing-s-Heavy-Lift-Concept-Matted-Print-Poster-/200780733142?pt=LH_DefaultDomain_0&hash=item2ebf76dad6
URL:
http://www.ebay.com/itm/Boeing-s-Heavy-Lift-Concept-Matted-Print-Poster-/200780733142?pt=LH_DefaultDomain_0&hash=item2ebf76dad6
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Artist's impression of Boeing Vertol XCH-62 (Model 301) Heavy Lift Helicopter (HLH) press photo circa 1973 found on eBay.
Source:
http://www.ebay.com/itm/1973-Boeing-Vertol-Division-sketch-Press-Photo-/200794612779?pt=Art_Photo_Images&hash=item2ec04aa42b
Source:
http://www.ebay.com/itm/1973-Boeing-Vertol-Division-sketch-Press-Photo-/200794612779?pt=Art_Photo_Images&hash=item2ec04aa42b
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The Boeing Vertol HLH;
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19820015368_1982015368.pdf
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19820015368_1982015368.pdf
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From NASA/HAA Advanced Rotorcraft Technology and Tilt Rotor Workshop. Volume 6: Vehicle Configuration Session
Source:
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19820015368_1982015368.pdf
Abstract:
Source:
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19820015368_1982015368.pdf
Abstract:
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What bugs me is that Boeing closed the door on flying cranes just because the HLH contract was cancelled.
If the idea had so much potential as these beautiful paintings suggest, why didn't they try to push the concept forward on the civilian market all the same?
If the idea had so much potential as these beautiful paintings suggest, why didn't they try to push the concept forward on the civilian market all the same?
Sikorsky sold the manufacturing rights to the S-64 Skycrane to Erickson Air-Crane of Portland, Oregon in 1992. Erickson refurbishes old S-64 helicopters and manufactures new S-64 Aircrane helicopters. Erickson Air-Crane is also the largest operator of S-64 helicopters.
I wonder how many units Boeing or Sikorsky would need to sell of skycranes to make it worth their while as opposed to a niche business.
I haven't seen skycrane helicopters used to unload and transport ISO Intemodal containers at sea or at cargo terminals. I could see the military being interested in doing this if they need to offload cargo at destinations with no local infrastructure, but commercial operations usually use ports with cargo handling equipment that can offload ISO Intermodal containers onto trucks or railroad cars. Seems to me that skycranes would be an expensive way to transport ISO Intermodal containers and cause noise and airspace congestion issues that would make them unpopular with civilian populations.
I wonder how many units Boeing or Sikorsky would need to sell of skycranes to make it worth their while as opposed to a niche business.
I haven't seen skycrane helicopters used to unload and transport ISO Intemodal containers at sea or at cargo terminals. I could see the military being interested in doing this if they need to offload cargo at destinations with no local infrastructure, but commercial operations usually use ports with cargo handling equipment that can offload ISO Intermodal containers onto trucks or railroad cars. Seems to me that skycranes would be an expensive way to transport ISO Intermodal containers and cause noise and airspace congestion issues that would make them unpopular with civilian populations.
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General arrangement and text excerpts about the Model 301 by Boeing Vertol (source):
Vehicle Description
The Boeing Vertol Model 301 is a heavy lift helicopter (HLH) designed to provide vertical airlift capability for large and heavy loads. As originally designed, it was configured as a 'crane' helicopter primarily designed to lift external loads such as standard shipboard container modules, slings, platforms or special pods. For study purposes, a civil transport version of the Model 301 also was investigated. This transport configuration would have a larger fuselage with the capability of transporting 140 passengers in a 7-abreast, dual-aisle airline arrangement. Although similar in many ways, each helicopter has sufficient differences to be treated separately for the crane and transport configurations.
The heavy lift helicopter, described in this section, is the result of an intensive design study performed for the U.S. Army. The HLH rotor system was assembled and whirled on both a rotor tower as well as an integrated powerplant/drive system test facility (DSTR) which included one rotor, transmissions, and engines.
Model 301 Crane
The Boeing Vertol Model 301 crane is a tandem rotor shaft-driven helicopter powered by three T701-AD-700 gas turbine engines of 8079 HP each. It provides a vertical airlift capability for loads carried externally beneath the fuselage utilizing either a single or two point suspension system. The crew compartment accommodates a pilot, copilot, flight engineer and load controlling crewman. A combination troop/light cargo compartment is aft of the crew compartment. Aft of the troop compartment, the center section contains the cargo handling equipment in the forward and aft positions. Each of the two hoists are located in this section.
The main rotors are four-bladed and operate at 156 RPM (750 fps tip speed). A fly-by-wire flight control system has been incorporated in the aircraft.
Model 301 Transport
The Boeing Vertol Model 301 transport, like the crane, is a tandem rotor, three engine helicopter. It has the same drive system and rotor as the crane, but the airframe is configured to transport 140 passengers. The load controllers cab and associated flight controls, etc. have been removed.
Noise Sources
Model 301 flyover noise levels have been estimated using measured test rig data as well as predirtive methodology. Noise levels were based on: (1) measurements of an HLH rotor on a whirl tower, (2) data obtained on the dynamic system test rig, (3) comparison with flyover noise levels measured on the Boeing Vertol Model 347 (similar rotor geometry to the Model 301), and (4) analytical predictions.
The basic approach to estimating Model 301 flyover EPNL was to relate it to Model 347 flyover data since overlap and rotor configuration are similar on the two helicopters. Therefore, PNL flyover time histories were assumed to have similar characteristics, although absolute levels differed.
Since rotor geometry, powerplants, drive system and gross weight are similar on the crane and transport configuration, noise sources are similar. Configuration changes on the transport rotor system also are the same as those for the crane.
Vehicle Description
The Boeing Vertol Model 301 is a heavy lift helicopter (HLH) designed to provide vertical airlift capability for large and heavy loads. As originally designed, it was configured as a 'crane' helicopter primarily designed to lift external loads such as standard shipboard container modules, slings, platforms or special pods. For study purposes, a civil transport version of the Model 301 also was investigated. This transport configuration would have a larger fuselage with the capability of transporting 140 passengers in a 7-abreast, dual-aisle airline arrangement. Although similar in many ways, each helicopter has sufficient differences to be treated separately for the crane and transport configurations.
The heavy lift helicopter, described in this section, is the result of an intensive design study performed for the U.S. Army. The HLH rotor system was assembled and whirled on both a rotor tower as well as an integrated powerplant/drive system test facility (DSTR) which included one rotor, transmissions, and engines.
Model 301 Crane
The Boeing Vertol Model 301 crane is a tandem rotor shaft-driven helicopter powered by three T701-AD-700 gas turbine engines of 8079 HP each. It provides a vertical airlift capability for loads carried externally beneath the fuselage utilizing either a single or two point suspension system. The crew compartment accommodates a pilot, copilot, flight engineer and load controlling crewman. A combination troop/light cargo compartment is aft of the crew compartment. Aft of the troop compartment, the center section contains the cargo handling equipment in the forward and aft positions. Each of the two hoists are located in this section.
The main rotors are four-bladed and operate at 156 RPM (750 fps tip speed). A fly-by-wire flight control system has been incorporated in the aircraft.
Model 301 Transport
The Boeing Vertol Model 301 transport, like the crane, is a tandem rotor, three engine helicopter. It has the same drive system and rotor as the crane, but the airframe is configured to transport 140 passengers. The load controllers cab and associated flight controls, etc. have been removed.
Noise Sources
Model 301 flyover noise levels have been estimated using measured test rig data as well as predirtive methodology. Noise levels were based on: (1) measurements of an HLH rotor on a whirl tower, (2) data obtained on the dynamic system test rig, (3) comparison with flyover noise levels measured on the Boeing Vertol Model 347 (similar rotor geometry to the Model 301), and (4) analytical predictions.
The basic approach to estimating Model 301 flyover EPNL was to relate it to Model 347 flyover data since overlap and rotor configuration are similar on the two helicopters. Therefore, PNL flyover time histories were assumed to have similar characteristics, although absolute levels differed.
Since rotor geometry, powerplants, drive system and gross weight are similar on the crane and transport configuration, noise sources are similar. Configuration changes on the transport rotor system also are the same as those for the crane.
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Boeing Vertol considered some modifications to improve on the Model 301. Here are some text excerpts and diagrams (same source as above):
Model 301 Crane
Configuration Changes - Tradeoff Variables
The modification includes new rotor blades, modified cockpit vibration absorbers, a new gear ratio for the generators and acoustically lined engine inlets.
Impact of Design Changes on Performance, Weight and Cost Performance
As noted for the CH-47, the 301 is a derivative of a military helicopter. At a gross weight of 118,000 pounds reductions in rotor speed to 141 RPM (681 ft/sec) are within the capability of the existing airframe and dynamic system.
In addition, at a mission radius of 3 nautical miles, for example, reduction of tip speed from 750 ft/sec to 681 ft/sec reduces rotor power required and SFC, effectively increasing
the number of sorties from 37 to-40. A reduction in payload of approximately 9000 pounds is associated with this rotor speed reduction, however, limiting the payload to 41,000 pounds. This represents a reduction in payload of 18 percent. Obviously, payloads in excess of 41,000 pounds would be the only loads affected.
Weight
The modification to the crane version of the Model 301 increases weight empty from 62,120 pounds to 63,534 pounds, an increase of 1414 pounds. This is comprised of an additional 643 pounds due to increased blade chord, 150 pounds for the retuned vibration absorbers and 621 pounds resulting from the lined engine inlet plenum area.
Cost
For the cost study, the mission of the Model 301 crane was based on 2.3 statute mile sortie as defined in the 'performance' section, cruising outbound at 90 knots to a work area. The hover pickup of load and inbound cruise, hover and deposit of load results in a block speed of approximately 49 mph.
Since the crane is designed to carry external loads, not passengers, the cost study was based on ton-mile rather than seat-mile costs. Ton-mile costs were developed from air-mile costs divided by the payload which is a function of tip speed. Thus, at a tip speed of 750 fps payload was approximately 25 tons while at 680 ft/sec the payload was reduced to 21 tons.
The Model 301 crane was considered to be a 'new' helicopter for this study with the implied assumption that nonrecurring costs were spread over the entire production base. This production base was assural over a range of 50 to 1000 units to display the effect which this varifebifi has on operating costs.
Modification 1 to the baseline crane configuration results in a 3 EPNdB reduction in flyover noise. Air-mile costs remain essentially unchanged as a result of the configuration change to the crane. However, the reduction in rotor tip speed from 750 to 685 ft/sec results in a reduction in payload from 25 tons to 21 tons resulting in a tonmile cost increase by 17-19.7 percent. If crane payload had been 21 tons or less initially, no increase in ton-mile costs would be incurred due to the reduced tip speed of Modification 1.
Reductions in flyover EPNL below that defined by Modification 1 did not appear to be achievable. A reduction in tip speed to 650 ft/sec with the increased solidity main rotor blade showed only a 1 dB reduction in Perceived Noise Level. Further reductions in rotor noise are not apparent for this 90 foot diameter rotor. Additional research is required in the area of broadband noise reduction of large rotors.
Model 301 Transport
Impact of Design Changes on Performance, Weight and Cost Performance
The transport mission is a two minute warmup at maximum continuous power and takeoff at sea level-standard day conditions, climbing to 2000 feet and cruising out at 99 percent optimum range and landing with a 45 minute fuel reserve for a 99 percent optimum range cruise speed. For the transport gross weight of 118,000 pounds which includes 25,000 pounds fuel and 140 passengers and baggage at 200 pounds each, no impact on pay load is noted to tip speeds of 665 ft/sec. Below this rotor speed, the number of passengers or fuel load would be reduced by a requirement to maintain a 35 degree band angle maneuver. Modification 1 operates at 681 ft/sec, which is within this limit.
Lower rotor power required results in an increase in cruise speed from 138 kt to 151 kt, a 9 percent increase. Similarly, the range increases from 417 to 545 nautical miles, an increase of 14 percent.
Weight
The weight empty of the transport increases by 1594 pounds for Modification 1, from 64,638 to 66,232 pounds. Note that for the transport, cockpit vibration absorber weight has been reduced to 100 pounds to reflect the deletion of the load controller's station. In addition, the floor isolation system must be retuned for Modification 1 to the baseline helicopter, adding 112 pounds to weight empty.
Cost
The mission of the Model 301 transport for this study as defined in the performance section consisted of a 100 seat mile flight at a cruise speed of 138 knots. This cruise speed represents 99 percent best range speed. Block speed associated with this is 125.8 knots. The transport configuration seats 140 passengers resulting in a design gross weight of 118,000 pounds. This gross weight is well below the engine torque limits for all rotor speeds, and the reduced tip speed of the Modification 1 configuration does not limit the transport payload capability.
The Model 301 transport was considered to be a 'new' helicopter for this program with all nonrecurring costs spread over the entire production base. As for the other aircraft in the study, the production base was evaluated over a range of 50 to 1000 units to determine the effect which this variable has on operating costs.
Changes in air mile costs resulting from Modification 1 changes to the transport version of the Model 301 produce only minimal changes in direct operating costs. As a 'new' aircraft, only those changes to the transport which incur additional material costs result in an increase in direct operating cost, since all nonrecurring is similar for both configurations. The additional material is in the wider chord blades, engine plenum acoustical linings, the retuned vibration absorbers in the cockpit and cabin floor and the fuel isolation system.
Further reductions in rotor noise for a rotor of this diameter (90 feet) are not apparent. Additional research is required to reduce the broadband component of large rotors.
Several cases of rotational and broadband noise evaluation showed that reduction in rotor speed alone without other rotor modifications resulted in no reduction in Perceived Noise Level for that rotor. This stemmed from an increasing average rotor lift coefficient as rotor speed was reduced having the effect of increasing broadband noise. The result was generally offsetting noise trends between rotational and broadband noise. Only when blade chord was increased did both rotational and broadband noise decrease.
Model 301 Crane
Configuration Changes - Tradeoff Variables
The modification includes new rotor blades, modified cockpit vibration absorbers, a new gear ratio for the generators and acoustically lined engine inlets.
Impact of Design Changes on Performance, Weight and Cost Performance
As noted for the CH-47, the 301 is a derivative of a military helicopter. At a gross weight of 118,000 pounds reductions in rotor speed to 141 RPM (681 ft/sec) are within the capability of the existing airframe and dynamic system.
In addition, at a mission radius of 3 nautical miles, for example, reduction of tip speed from 750 ft/sec to 681 ft/sec reduces rotor power required and SFC, effectively increasing
the number of sorties from 37 to-40. A reduction in payload of approximately 9000 pounds is associated with this rotor speed reduction, however, limiting the payload to 41,000 pounds. This represents a reduction in payload of 18 percent. Obviously, payloads in excess of 41,000 pounds would be the only loads affected.
Weight
The modification to the crane version of the Model 301 increases weight empty from 62,120 pounds to 63,534 pounds, an increase of 1414 pounds. This is comprised of an additional 643 pounds due to increased blade chord, 150 pounds for the retuned vibration absorbers and 621 pounds resulting from the lined engine inlet plenum area.
Cost
For the cost study, the mission of the Model 301 crane was based on 2.3 statute mile sortie as defined in the 'performance' section, cruising outbound at 90 knots to a work area. The hover pickup of load and inbound cruise, hover and deposit of load results in a block speed of approximately 49 mph.
Since the crane is designed to carry external loads, not passengers, the cost study was based on ton-mile rather than seat-mile costs. Ton-mile costs were developed from air-mile costs divided by the payload which is a function of tip speed. Thus, at a tip speed of 750 fps payload was approximately 25 tons while at 680 ft/sec the payload was reduced to 21 tons.
The Model 301 crane was considered to be a 'new' helicopter for this study with the implied assumption that nonrecurring costs were spread over the entire production base. This production base was assural over a range of 50 to 1000 units to display the effect which this varifebifi has on operating costs.
Modification 1 to the baseline crane configuration results in a 3 EPNdB reduction in flyover noise. Air-mile costs remain essentially unchanged as a result of the configuration change to the crane. However, the reduction in rotor tip speed from 750 to 685 ft/sec results in a reduction in payload from 25 tons to 21 tons resulting in a tonmile cost increase by 17-19.7 percent. If crane payload had been 21 tons or less initially, no increase in ton-mile costs would be incurred due to the reduced tip speed of Modification 1.
Reductions in flyover EPNL below that defined by Modification 1 did not appear to be achievable. A reduction in tip speed to 650 ft/sec with the increased solidity main rotor blade showed only a 1 dB reduction in Perceived Noise Level. Further reductions in rotor noise are not apparent for this 90 foot diameter rotor. Additional research is required in the area of broadband noise reduction of large rotors.
Model 301 Transport
Impact of Design Changes on Performance, Weight and Cost Performance
The transport mission is a two minute warmup at maximum continuous power and takeoff at sea level-standard day conditions, climbing to 2000 feet and cruising out at 99 percent optimum range and landing with a 45 minute fuel reserve for a 99 percent optimum range cruise speed. For the transport gross weight of 118,000 pounds which includes 25,000 pounds fuel and 140 passengers and baggage at 200 pounds each, no impact on pay load is noted to tip speeds of 665 ft/sec. Below this rotor speed, the number of passengers or fuel load would be reduced by a requirement to maintain a 35 degree band angle maneuver. Modification 1 operates at 681 ft/sec, which is within this limit.
Lower rotor power required results in an increase in cruise speed from 138 kt to 151 kt, a 9 percent increase. Similarly, the range increases from 417 to 545 nautical miles, an increase of 14 percent.
Weight
The weight empty of the transport increases by 1594 pounds for Modification 1, from 64,638 to 66,232 pounds. Note that for the transport, cockpit vibration absorber weight has been reduced to 100 pounds to reflect the deletion of the load controller's station. In addition, the floor isolation system must be retuned for Modification 1 to the baseline helicopter, adding 112 pounds to weight empty.
Cost
The mission of the Model 301 transport for this study as defined in the performance section consisted of a 100 seat mile flight at a cruise speed of 138 knots. This cruise speed represents 99 percent best range speed. Block speed associated with this is 125.8 knots. The transport configuration seats 140 passengers resulting in a design gross weight of 118,000 pounds. This gross weight is well below the engine torque limits for all rotor speeds, and the reduced tip speed of the Modification 1 configuration does not limit the transport payload capability.
The Model 301 transport was considered to be a 'new' helicopter for this program with all nonrecurring costs spread over the entire production base. As for the other aircraft in the study, the production base was evaluated over a range of 50 to 1000 units to determine the effect which this variable has on operating costs.
Changes in air mile costs resulting from Modification 1 changes to the transport version of the Model 301 produce only minimal changes in direct operating costs. As a 'new' aircraft, only those changes to the transport which incur additional material costs result in an increase in direct operating cost, since all nonrecurring is similar for both configurations. The additional material is in the wider chord blades, engine plenum acoustical linings, the retuned vibration absorbers in the cockpit and cabin floor and the fuel isolation system.
Further reductions in rotor noise for a rotor of this diameter (90 feet) are not apparent. Additional research is required to reduce the broadband component of large rotors.
Several cases of rotational and broadband noise evaluation showed that reduction in rotor speed alone without other rotor modifications resulted in no reduction in Perceived Noise Level for that rotor. This stemmed from an increasing average rotor lift coefficient as rotor speed was reduced having the effect of increasing broadband noise. The result was generally offsetting noise trends between rotational and broadband noise. Only when blade chord was increased did both rotational and broadband noise decrease.
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Model of Boeing XCH-62A Heavy Lift Helicopter manufactured by Topping found on eBay.
Source:
http://www.ebay.com/itm/300590326146?nma=true&si=mQt59qMSk235qeqNTmClfG9NAAc%3D&rt=nc&_trksid=p4340.l2557&orig_cvip=true
Source:
http://www.ebay.com/itm/300590326146?nma=true&si=mQt59qMSk235qeqNTmClfG9NAAc%3D&rt=nc&_trksid=p4340.l2557&orig_cvip=true
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A sad footnote to the history of the XCH-62. There was a meeting going on concerning the Joint Heavy Lift project (the latest doomed heavy lift effort), when we got word that the XCH-62 at Ft. Rucker was being destroyed as we sat there. The meeting immediately went on break and a number of us drove over to the demolition site. After a couple of minutes of talking with the contractor (who was baffled why anyone would want to rummage around in scrap metal), we secured the ident plates, sticks & grips, along with the huge external hook that would have picked up howitzers.
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Shipping costs are a lot cheaper here... so I'm bidding.
Artist's impression poster for the Boeing Heavy Lift Helicopter (HLH), which was later designated XCH-62, found on eBay.
Source:
http://www.ebay.com/itm/Signed-15X18-Poster-Boeing-Vertol-Divison-Heavy-Lift-Helicopter-Concept-Army-/231386011353?pt=LH_DefaultDomain_0&hash=item35dfae56d9
Source:
http://www.ebay.com/itm/Signed-15X18-Poster-Boeing-Vertol-Divison-Heavy-Lift-Helicopter-Concept-Army-/231386011353?pt=LH_DefaultDomain_0&hash=item35dfae56d9
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The image shared by sferrin did not quite depict the XCH-62A but some other Boeing Vertol concepts.
We already had it here:
http://www.secretprojects.co.uk/forum/index.php/topic,565.msg182711.html#msg182711
I have therefore moved the post to that topic.
We already had it here:
http://www.secretprojects.co.uk/forum/index.php/topic,565.msg182711.html#msg182711
I have therefore moved the post to that topic.
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Good Day All!
A recent donation of Army Aviation material to the Museum has delivered some Boeing Vertol HLH material to add to this thread. I have some photos of a briefing room for an HLH presentation I need to scan - walls are covered in prints, vuegraphs and artwork and there are a number of models in the images as well. I'll post those once I get them scanned. In the meantime here's two trifold brochures on the HLH. I don't know which was published/printed first - I find it interesting one is Boeing Vertol Company and the other just Boeing.
The donor was heavily involved in the acquisition process for the HLH and for the AH-56 - we will be interviewing him in about a month and the subject of just what the HLH/XCH-62 at Ft. Rucker was (mock up, test rig, prototype) is on my list of questions.
Enjoy the Day! Mark
A recent donation of Army Aviation material to the Museum has delivered some Boeing Vertol HLH material to add to this thread. I have some photos of a briefing room for an HLH presentation I need to scan - walls are covered in prints, vuegraphs and artwork and there are a number of models in the images as well. I'll post those once I get them scanned. In the meantime here's two trifold brochures on the HLH. I don't know which was published/printed first - I find it interesting one is Boeing Vertol Company and the other just Boeing.
The donor was heavily involved in the acquisition process for the HLH and for the AH-56 - we will be interviewing him in about a month and the subject of just what the HLH/XCH-62 at Ft. Rucker was (mock up, test rig, prototype) is on my list of questions.
Enjoy the Day! Mark
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Going through a friends estate, I found the Aircraft Geometry Basic Points drawing for the Model 301.
I looked through this topic and did not see this drawing in the previous posts.
I see Scott is trying to sell the inboard profile, so won't post my scans.
I looked through this topic and did not see this drawing in the previous posts.
I see Scott is trying to sell the inboard profile, so won't post my scans.
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Last edited:
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