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Kachia’s Kmax logging Dismal Mtn 2/97

Hurricane Fran Blowdown Salvage


Kachia’s Kmax logging Dismal Mtn 2/97

Showing service landing in background



Presented at:





Hank Sloan

Roanoke, VA



Jim Sherar

Asheville, NC


ABSTRACT:  Three harvesting alternatives were considered to salvage Appalachian Hardwoods blown down by Hurricane Fran 9/96.  Helicopter Logging was the chosen Alternative, being the least costly, least impacting, and allowing salvage of the most timber.  A case study of the KMAX Helicopter Production and Costs for the project indicate production average 10.7 mbf/hr at a cost of $209/mbf International.  Comparison of case study results to estimates by HELIPACE, a PC program to simulate helicopter production and costs, indicate estimates for the KMAX may need refining.


Key Words:  Helicopter, Logging, Helipace, KMAX






On September 6, 1996 Hurricane Fran impacted the dismal mountain Area on the Pedlar Ranger District, approximately 5 miles west of Lowesville, Va.  The damage to the forest consisted mainly of blown down trees and broken tops in a variety of intensities ranging from scattered individual trees to areas of complete collapse of the dominant forest.  This paper looks at the alternative methods of harvest which were considered, presents a case study of the implemented helicopter logging, and reviews the effectiveness of the computer program Helipace (Aerial Forest Management Foundation, 1996) to predict costs based upon the case study results.





The sawtimber that blew down was subject to rapid deterioration in the 1997 growing season due to staining.  The specie composition was 80% Yellow Poplar, 20% Northern Red Oak.  The damaged sawtimber component would be characterized as High Quality in a market where the industrial demand is outstripping the available supply (Sloan, 1995).  The damaged small roundwood component of this timber is very common in the market area, and of little economic value, either in terms of stumpage receipts or in meeting industrial demands for forest products.  Available supply of small roundwood exceeds industrial demand (Sloan, 1995).  The focus of this salvage effort was therefore on the sawtimber component.


The salvage area terrain is characterized as rocky with extensive steep slopes, >35%.  The soils are shallow with bedrock surface exposure in several areas.  The ownership pattern was such that some salvage areas could not be accessed by ground due to a lack of easement.  These factors restrict the operability of logging systems.


Three harvesting alternatives for the salvage of the blown down timber were considered.  1) Conventional cable skidder with forwarder swing, 2) Downhill skyline with cable skidder bunching, and 3) Helicopter Logging.


Alt. 1  conventional logging with forwarder swing


Due to the steep ground, an extensive network of skid roads would be required in this alternative.  Given the shallow soils and bedrock exposures this alternative also presented some risk associated with the ability to build skid roads without blasting.  These same factors also limit the ability to build truck road in the area.  In lieu of building truck road, a forwarder road was considered more feasible, utilizing forwarding to a full service landing at an existing truck road.  The forwarder road would require the construction of a temporary bridge to cross Kings Creek, a trout fishery.  This logging system alternative is the closest match to the area’s conventional systems and, being common, would theoretically make the timber sale offering have the greatest market exposure.  However, the difficult terrain and the availability of forwarders would limit significantly this alternative’s marketability.  The timber that was blocked by lack of easement would not be salvaged.  This alternative’s projected sale volume was 621 mbf (International 1/4”).  Given the mid winter sale date, it is likely that harvest operations under this alternative would be delayed until early spring and production would be limited by the forwarding swing to the truck road.  Given the average skid of 800 ft combined with a 2400 ft average forward, the logging system production is estimated at 9-10 mbf/day.  At this rate of logging production the harvest would conclude in late summer/early fall of 1997.  The staining of the sawtimber would begin to occur in late spring, and by harvest end would be quite heavy.  The value loss due to stain degrade would be high.


Alt. 2 downhill skyline with cable skidder bunching


In order to reduce the ground impacts and risks associated with road building, an alternative using a downhill skyline system was developed.  In areas where there was insufficient deflection for skylining, a cable skidder would be used to bunch the timber under a skyline corridor.  The timber that was blocked by lack of easement would not be salvaged.  Approximately half of the estimated 621 mbf in this alternative would need to be both skidded and yarded.  The cable skidder would need to have a system of roads built, although this alternative would reduce the roading required by approximately 40%.  Harvesting could begin without delay in the half of the area to be yarded directly, delaying skid road building until seasonal weather permitted.  The logging system production for this alternative is estimated to be 12-15 mbf/day.  At this

rate of logging the harvest would conclude in mid summer, and by harvest end value loss due to stain degrade would be moderate.


Alt. 3 helicopter


Given the rough terrain, the trout fisheries, inaccessible timber, and the fairly intense amount of development required in the first two alternatives a helicopter alternative was planned.  The timber that

was land locked to ground based systems could be harvested, and this alternative’s projected sale volume was 925 mbf.  Estimated volumes of removal in the 10+ mbf/ac range provided the opportunity to hook full turns and minimize helicopter costs.  Initially, it was thought that an optimal number and spacing of landings could be selected to minimize helicopter costs.  The environmental analysis process, however eliminated all landing opportunities except one, due to cultural resource protection or Land Management Planning allocations.  Fortunately this landing location was fairly central to the timber to be salvaged.  Production for this alternative was estimated to be 80-100 mbf/day, and logging production could begin without delay.  At this rate of logging the harvest would conclude in late winter,

prior to any loss due to stain degrade.  See figure 1. for map of this alternative.



 Figure 1. Dismal Helicopter Salvage Sale Map




Table 1. Harvest alternative comparison.



                                                            Alternative 1                     Alternative 2                     Alternative 3     

                                                            Cable Skid                           Skyline with Cable             Helicopter

                                                            Forwarder Swing                Skid Bunch                                          

                                                                           Total                                    Total                                    Total

                                                            #             Cost                      #             Cost                      #             Cost


Landings                                             2 ea        $1200                   4 ea        $2000                   1 ea        $6000

Swing Landing                                   1 ea           600                   

Forwarder Road                                 2400 ft    3000

Forwarder Bridge                              1 ea          4200

Skid Road                                           8000 ft    7000                   4600 ft     4000

Swing Vol.                                          544 mbf   24480                 345 mbf   17250

Logging Costs 1                                 621 mbf 62100                  621 mbf   74250                 925 mbf   130425

Total Vol.                                           621 mbf                               621 mbf                               925 mbf

Total Costs                                                        102580                                97770                                  136425

Unit Rate 2                                         $165.20/ mbf                      $157.40/ mbf                      $147.50/ mbf

Estimated time to harvest                 7 months                             5 months                             1 month

Potential Deterioration                    High                                     Medium                               None       



1 Fell and Skid/Yard Rates estimated by Alt are:  Alt 1. $100/mbf;  Alt 2. $120/mbf;   Alt 3. $141/mbf

2 Costs are stump to landing



Decision to utilize helicopter logging


The decision to use the helicopter alternative was based upon these factors:

     1.  Salvaged the most timber.

     2.  Estimated to be the most cost effective.

     3.  Estimated to have the least soil, water,

          fisheries, visual impacts.

     4.  Minimized the risk of developments in rugged   terrain.

     5.   Minimized loss in value due to stain degrade.


Helicopter logging is normally thought of as the most expensive logging method.  As this comparison shows that is not always the case.  There are no “rules of thumb” which can be applied to logging system selections.  A comparison of typical unit rates for logging systems is not sufficient to portray enough information to base a reliable decision.  Each alternative must be developed in sufficient project detail to allow for specific cost estimates,  environmental impacts and risk assessment.


It is possible to identify when helicopter logging should be considered as an alternative.  These factors are when:

     1.  Conventional logging costs are higher than            

normal and particularly when swing systems are needed.


2.  When conventional logging systems can not

access all timber, either through operability

limitations or ROW easement limitations.


 3.  When environmental impacts from conventional logging are heavy or unlawful.  This includes timber with BMP restrictions such that it either eliminates harvest conventionally or forces BMP variance to harvest conventionally. 


4.  When road costs are higher than normal, or

when permanent access is not needed for future management.


5.   When quick salvage is necessary over large areas due to substantial risk of degrade, particularly during weather related inoperable seasons.





The Dismal Salvage Helicopter sale was prepared under the Recission Act legislation (Salvage Rider, Section 2001 (f( (1) Public Law 104-19) which made the environmental decision to harvest not subject to administrative appeal.  This act expired December 31, 1996 and due to administrative limitations late in the year, any timber sale under this legislation needed to be awarded by year end.  If not awarded by year end the decisions to make the sale would need to revert to a “normal” environmental analysis process lasting at best 6 months.  This would effectively eliminate the need to salvage, as the timber would be wasted due to deterioration and of little remaining value.


This timber sale was a “fast track” project with the time of awareness of the salvage opportunity to time of bidding less than three months.  The Glenwood Ranger District Timber Management Assistant, Glenn Szarzynski, is the man credited with providing the leadership and coordination that made this project a timely and successful salvage operation.  The sale was formally advertised December 12, bids opened December 30th, and award was made on December 31st, 1996.


The advertised minimum acceptable price for the 936 mbf was $41,000.  Two bids were received, one of  $55,567 and the high bid of $102,003.  Kachina Forest Products, Boise, ID, was the successful bidder.


Kachina Forest Products was formed as a partnership between Kachina Aviation and George Jenson Logging in 1996.  This partnership combined over 50 years of aviation and logging expertise to focus on the business of heli-logging.  Kachina Forest Products is interested in contract heli-logging opportunities with their KMAX helicopter.  They may be contacted by calling Keith Watson, (208) 343-8749.


Equipment Utilized:

    Helicopter:  KMAX, 6000# lift capacity, Cost                                     $3,500,000

    Other:  1400 gallon Jet A Fuel Truck, Aircraft maintenance trailer, Dozer (Landing Construction, CAT D5C), Front End Loader (CAT 1T28F), Knuckleboom Loader with Buck Saw (Prentice 180), Skidder (Landing Clearing, Timberjack 380B), 4 subcontract Log Trucks


The contract was executed and paid for January 8, 1997 and cutting began January 10, 1997.  Timber falling conditions were extremely difficult due to Hurricane Fran’s fury.  The timber was in places blown down in jackstrawed layers 4 deep, root wads, broken boles and tops, on very steep (65%+) ground.  The cutting job was subcontracted to Ross Hojem, Hojem Logging, out of Chehalis, WA.  Ross and crew did an excellent job in dealing with these dangerous cutting conditions.  Ross had never cut for a helicopter job, but he has worked extensively with a wide range of logging systems on steep ground.  He also had valuable experience cutting Appalachian Hardwoods (Sloan, 1992), something that Kachina Forest Products lacked.  Timber cutting production average 10mbf/man-day, and was done with safety in

operations as first priority.  No cutting occurred on windy days, length of work day was controlled to minimize fatigue, and communication was maintained between the cutting crew members.   The cutting contract rate was $22/mbf International.


Both the service and log landing construction was accomplished with a rented Caterpillar D5C dozer.  Along with some minor road widening, the landing clearing and construction process took a full week.  In order to armor the landing for winter season work, 400 tons of Va #2 stone (3-4”/dia) was placed.  The cost of these landings were $2100 D5C, $4800 stone, $1500 labor for a total cost of $8400.


Flying of the timber began on January 23 with a schedule of working Monday through Saturday when not limited by visibility or wind (>35mph).   The following table represents a summary of the production data recorded during the project.


Table 2. KMAX production data record

Date                Total             Total               Aborts             Flights           Turns/                Pounds/

                        Pounds         Turns                #                   Hours             Hour                   Turn


1/23/97            382380               81                 4                    3.6                22.5                    4721

1/24/97            333590               70                 6                    3.6                19.4                    4766

1/27/97            699890             146                 7                    6.5                22.5                    4794

1/29/97            706750             151               12                    6.9                21.9                    4680

1/30/97            778390             172                 6                    6.9                24.9                    4526

1/31/97            748690             164                 7                    7.0                23.4                    4565

 2/1/97             699010             156                 5                     6.6                23.6                    4481

 2/3/97             826420             189                                        6.7                28.2                    4373

 2/4/97             751200             162                                        6.3                25.7                    4637

 2/5/97             867500             193                                        6.3                30.6                    4495

 2/7/97             795200             186                                        5.5                33.8                    4275

 2/10/97           152360               37                                        1.2                30.8                    4118

 2/11/97           461720             104                                        3.6                28.9                    4440

 2/15/97           609620             140                                        4.9                28.6                    4354

 2/18/97           897310             198                                        7.3                27.1                    4532

 2/19/97           402070               94                                        3.5                26.9                    4277


Totals           10112100          2243                47                  86.4                26.0                    4508





Total timber sale cruised volume to be flown was 925 mbf International broken down as follows:

     Species Group      MBF International

     Yellow Poplar                  743

     Red Oak                          174

     Misc HWD                          8


Based upon the cruised volume and the actual flight records, production for the KMAX was 10.7 mbf/hr International.


Total timber sale delivered volume as recorded from mill receipts was 754 mbf Doyle broken down as follows:

   Species              MBF Doyle

   Yellow Poplar          595

    Red Oak                  109

    Chestnut Oak            27

    Ash                             7

    Hickory                       6

    Hard Maple                 3

    Basswood                    3

    Soft Maple                   2

    Misc.                           2


Based upon the delivered volume and the actual flight records, production for the KMAX was 8.73 mbf/hr Doyle.


One of the most critical factors in determining the aircraft costs is the utilization rate of the aircraft.  Annual utilization can be projected from this project, based upon the availability of the aircraft to fly with weather delays and scheduling conflicts.  On this project 86.4 flight hours were recorded with 23 scheduled days.  The projected utilization rate is (86.4/23)* 300 scheduled days/year =1127 hours/year.  Based upon this annual utilization rate, the projected cost for the KMAX is estimated to be $1615/flight hour (Sloan, 1994).


The unit rate for the KMAX flight operations only would be:


     $1615/10.7 = $151/mbf International

     $1615/8.73 = $185/mbf Doyle


In addition to the flight costs, there were 4 hookers, 2 chasers, and 1 loader with operator to support the job.  Estimated cost for this is $150/man-day average plus $500/day for the loader.  The number of days worked was 16 days.
The unit rate for hooking, chasing, and clearing the chute would be:

     ($150*7*16)+($500*16)/ 925 MBF = $27/mbf International

     ($150*7*16)+($500*16)/ 754 MBF = $33/mbf Doyle



Table 3. Total unit rate cost[2] for KMAX helicopter salvage


                                              $/MBF            $/MBF

                                             International         Doyle

Felling                                         22                    27

Flying                                        151                  185

Hooking, Chasing, Clearing        27                    33

Landing  Construction                   9                    11

Total Stump to Landing             209                  256


1 These costs exclude mobilization, travel, and profit



During the operation, there were some observations where improvements in productivity might be possible.  There was not enough lead time between the cutting operations and the yarding operations.  This resulted in an approximate 4 day delay in the yarding where the KMAX could have flown, but there was no timber cut to be flown.  By planning helicopter operations, and scheduling enough lead time, this delay could be avoided.  The lack of Kachina Forest Products experience in Appalachian hardwood timber, combined with extremely difficult cutting conditions, undoubtedly contributed to this delay.  The load factors, actual turn weight/available turn weight, could be improved.  With the average cut per acre of 13.2 mbf Int. or 10.8 mbf Doyle, there was ample opportunity to hook full turns.  The average load factor was 4508#/6000# = 75%.  The target load was 5000#, or a load factor of 5000#/6000# = 83%.  By utilizing different techniques (Sloan, 1994) it is felt that this can be improved.  The variability in density in Appalachian hardwoods needs to be accounted for in the process of turn building.  Kachina Forest Products has reported average loads of 5200# on western projects, indicating that the inexperience in Appalachian hardwoods contributed to the below average load factor on this project. 


The yarding distance on this sale averaged 2700ft, with the closest unit 1300ft and the longest 4300ft.  In analyzing the turns per hour the average was 26 with the fastest being 33.8 and the slowest of 19.4.  An equation set for turns per hour, tons/hr, mbf/hr, and $/mbf based upon this projects logging conditions and flight distance would be approximately:


Turns/flight hour = 33.8 - .0048*(flight dist., ft -



Tons/flight hour = 76.2 - .0108*(flight dist.,ft. - 1300)


MBF Int/hr = 13.9 - .00198*(flight dist.,ft - 1300)


MBF Doyle/hr = 11.4 - .00161*(flight dist., ft -



$/MBF Int. = 1000/(6.52 - .000926(flight dist., ft - 1300)


$/MBF Doyle = 1000/(5.31 - .000755(flight dist., ft - 1300)


Both $/MBF equations do not include landing cost, mobilization, or profit





In order to effectively plan and appraise timber value in helicopter timber sales the USFS in concert with the Aerial Forest Management Foundation developed a PC based computer simulation program to model production and costs for heli-logging called Helipace (Aerial Forest Management Foundation, 1996).  The program was introduced in 1990, and has gone through numerous updates, with the latest version being 2.71 (1997) and includes the KMAX

helicopter.  In order to test the effectiveness of the program to predict production and costs, a comparison of this case study results to that predicted by Helipace is made.


In order to make the comparison, the actual values for pounds per board foot and pounds per turn from this case study were input along with all the other data required to run the Helipace program.

Table 4.  A comparison between the production estimated by Helipace and the case study results


                            Helipace 2.71        Case Study             

                                           Int.                         Int.

Unit  Flight dist  Turns/       mbf/      Turns/       mbf/

           Feet           Hr             hr             hr            hr

1         1346         25.6         10.6          33.6        13.8

2         2214         23.5           9.6          29.4        12.1

3         3204         21.4           8.9          24.6        10.1

4         4307         19.4           8.0          19.4          7.9

5         3004         23.9           9.9          25.6        10.5

6         3043         21.7           9.0          25.4        10.4



It appears from the above case study comparison table that Helipace as an estimator for the KMAX tends to underestimate productivity at shorter average yarding distances.  In viewing the aircraft coefficients used in Helipace, the same base times and coefficients are used for the KMAX as that for much larger ships.  It appears that coefficients specific for the KMAX need to be developed to increase the accuracy of the productivity estimates.


A comparison between the costs estimated by Helipace and the case study results are shown in the following table.


Table 5. Comparison betweeen the costs estimated in Helipace and case study.


                              Helipace 2.71  Case Study

Unit      Flight dist   $/MBF Int      $/MBF Int

1              1346        163                 154

2              2214        183                 177

3              3204        201                 210

4              4307        221                 268

5              3004        180                 202

6              3043        198                 204




It appears that from the above case study comparison table that Helipace tends to overestimate costs at shorter yarding distances and underestimate costs at longer yarding distances.  This variance can, in part,  be explained by the difference in the productivity previously outlined.  Further explanation can be made by examining the costs in the program for the KMAX.  The total cost in the program is $1311.50/hr, which is considerably less than the $1615/hr used in this case study.  This difference could be in the annual utilization rate.  If the annual utilization of the KMAX were 1500 hr/yr the costs for the KMAX are estimated at $1324.07/hr (Sloan,


1994).  This rate of utilization would yield costs which are in closer alignment with the

costs included in Helipace.  If the delays due to poor scheduling of lead time for timber falling are taken out from this study’s estimate of annual utilization, the predicted utilization would change to 1364 hr/yr.  These estimates of utilization do not include move time.  It is unlikely that for a contract heli-logging company, moving around the country for work, would get annual utilization of much greater than 1200-1400 hrs/yr.  Helipace does not include information on the annual utilization rate used in costing, nor the ability to adjust it, or any other cost variables for specific situations.


Additional concerns for predicting KMAX costs using HELIPACE are mobilization.  The program does not allow the user  to modify the equipment spread and people that must be mobilized, and is fixed on the mobilization needs of a larger aircraft.


The Helipace program is an excellent tool to become aquatinted with the variables associated with helicopter logging.  Hopefully, there will be continuing support which will keep it current as the technology of heli-logging changes.




Aerial Forest Management Foundation; USDA Forest Service PNW. 1996. HELIPACE Helicopter Logging Production and Cost Estimation. Program Documentation, Canby, Or. 51p.


Sloan, H.; LeDoux, C.; McWilliams, W.; Worthington, V.; Sustainability of Forest Products Production in the Jefferson National Forest Market Area.  In: Proceedings of the 1995 Council on Forest Engineering; 1995 June 5-8; Cashiers, NC.; 100-120.


Sloan, W.H.; Shovel Logging in the Mountains of Virginia.  In: Forest Engineering--Challenges in the Southern Appalachians Southern Council in Forest Engineering 1992; 1992 April 20-22; Blacksburg, VA: 1-4.


Sloan, H.; Technology Advances in Heli-logging:  A Case Study of the KMAX.  In:  Proceedings of the 1994 Council on Forest Engineering; 1994 July 24-29; Portland, OR:  237-246.

[1] Presented at the meeting of the Council On Forest Engineering, Rapid City, SD, July 28-July 31, 1997.


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