NASA Technical Reports Server (NTRS) 20000095082: A Characterization of the Terrestrial Environment of Kodiak Island, Alaska for the Design, Development and Operation of Launch Vehicles

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by  NASA Technical Reports Server (NTRS)

P6.6 A CHARACTERIZATION OF THE TERRESTRIAL ENVIRONMENT OF KODIAK, ALASKA
FOR THE DESIGN DEVELOPMENT, AND OPERATION OF LAUNCH VEHICLES
Michael A. Rawlins, Raytheon ITSS/MSFC Group, Huntsville, AL
Dale L.Johnson, NASNMSFC/ED44, Huntsville, AL
Glen W. Batts, Computer Sciences Corporation, Huntsville, AL
1. Importance of Natural Terrestrial Environment To be most beneficial, terrestrial environment
Definitions definitionsshoulda) beavailable attheinceptionofthe
program and based onthedesired operational
A quantitative characterization ofthe terrestrial performance ofthelaunch vehicle, b)be issued under
environment is an important component inthe success thesignature oftheprogram manager and bepartofthe
of a launch vehicle program. Environmental factors controlled program definitionand requirements
such as winds, atmospheric thermodynamics, documentation, andc) specifythe terrestrial
precipitation, fog, and cloud characteristics are among environment for all phases of activityincludingpre-
many parameters that must be accurately defined for launch, launch,ascent, on-orbit, decent, and landing
flight success. The National Aeronautics and Space (Pearson, etal., 1996). Since thebeginning ofthe
Administration (NASA) iscurrently coordinating weather space era, NASA has utilized some ofthemostdetailed
support and performing analysis for the launch of a assessments oftheterrestrial climatic environment in
NASA payload from a new facility located at Kodiak design, development, andoperations ofboth
Island, Alaska in late 2001 (NASA, 1999). Following the expendable and reusable launch vehicles. Projects
first launch from the Kodiak Launch Complex, an Air such as theSatum V, Space Transportation System
Force intercontinental ballistic missile on November 5, (STS), alsoknownas the Space Shuttle program, and
1999, the site's developer, the Alaska Aerospace newprograms suchas X-33 and X-37 haveall reliedon
Development Corporation (AADC), is hoping to acquire environments definitions from bothobserved
a sizable share of the many launches that will occur meteorological data (Meteorology Group Range
over the next decade. One suchcustomer is NASA, Commanders Council, 1983) andatmospheric models
which is planning to launch the Vegetation Canopy Lidar (Adelfang etal., 1994; Justus andJohnson, 1999).
satellite aboard an Athena Irocket, the first planned
mission to low earth orbit from the new facility. To 2. U.S Standard Atmosphere
support this launch, astatistical model of the
atmospheric and surface environment for Kodiak Island, The first modern standard atmosphere was
AK has been produced from rawinsonde and surface- developed inthe early 1920's by United States and
based meteorological observations for use as an input European advisory committees inorder to establish
to future launch vehicle design and/or operations. In standardization of aircraft instruments andperformance
this study, the creation of a "reference atmosphere" from (COESA, 1962). A standard atmosphere, as defined by
rawinsonde observations is described along with the World Meteorological Organization (WMO) is, ".. A
comparisons between the reference atmosphere and hypothetical vertical distribution of atmospheric
existing model representations for Kodiak (Rawlins and temperature, pressure, and density which, by
Johnson, 2000). Meteorological conditions that might international agreement, is roughly representative of
result inadelay on launch day (cloud cover, visibility, year-round, mid latitude conditions..." (U.S. Standard
precipitation, etc.) are also explored and described Atmosphere, 1976). Developed from theory, these
through probabilities of launch by month and hour of tables contained values of atmospheric properties to a
day. This atmospheric "mission analysis" is also useful geopotential altitude of 300 km. Sponsors ofthis effort
during the early stages of avehicle program, when included NASA, the National Oceanic and Atmospheric
consideration of the climatic characteristics of a location Administration (NOAA), and the United States Air Force.
can be factored intovehicle designs. Intime, reliable rocket and satellite data made possible
the definition of atmospheric properties up to 1,000 km
and in 1961 a new Working Group of the Committee on
Extension to the Standard Atmosphere (COESA) was
convened with thetask of developing a new standard
atmosphere. The U. S. Standard Atmosphere, 1962 is
divided into four altitude ranges, -5to 20 km, 20 to 32
km, 32 to 90 km, and 90 to 700 km. A revision
Corresponding author address: Michael A.Rawlins, incorporating new solar data was published in 1976, and
Raytheon ITSS/MSFC Group. NASA/MSFC/ED44, subsequent analysis showed that densities are about
Huntsville, AL 35812. 10% lower in the 70- to 80-km region and 10% higher in
Phone: [phone], Fax: [phone], the 90-km region than inthe 1962 Standard (U. S.
Email: michael.rawlins @msfc.nasa.gov Atmosphere, 1976).
3. Global Reference Atmospheric Model 4. Rawinsonde and Surface Data for Kodiak
Standard atmospheric models have been used Atmospheric thermodynamics and windparameters
repeatedly over theyears foraerospace vehicledesign (mean speed, direction,and U and Vcomponents) are
and missionplanning. However, early modelssuchas computed from a setoftwice-daily rawinsonde ascents
theU. S. Standard Atmosphere (1962 and 1976) have for Kodiak, AK from 1973-1995. Temporal consistency
no spatialvariability andonlylimited temporal ofthedata isverygood, withan average of-60
variability. The NASA/MSFC Global Reference soundingsper monththroughthe period. Quality
Atmospheric (GRAM) fills thisvoid. GRAM contains Controlprocedures, includingverticalconsistency and
gridded(2.5 X2.5 degree) monthlymean estimates of limitscheckswere applied toeach sounding inorderto
windand thermodynamic parameters derived from eliminate erroneous data. Soundings were also
rawinsonde andaircraftobservations (Justusand screened forobvious errorssuch aswind directions
Johnson, 1999), and providescomplete global greaterthan 360°orless than 0°orair temperatures
geographic coverage and altitudecoverage from the greaterthan 40 °C (104 °F). Furtherchecks ensured
surface toorbitalaltitudes. GRAM alsohas the thatpressures decreased throughthesounding.
capability tosimulate spatialandtemporal perturbations Soundings passingquality controlchecks were
representing phenomena suchas turbulence, interpolated to50-meter intervals from thesurface to30
mesoscale processes, and baroclinicwaves. kmandthen averaged (bymonth) over theperiod 1973-
GRAM-99, the latest versionofthemodel, isa 1995 tocreate the"Empirical" Kodiak Reference
combination ofthree empirically based modelsthat Atmosphere (KRA). Only data atmandatory reporting
represent differentaltitude ranges. The Global Upper levelswas usedtocreate each individualinterpolated
AirClimaticAtlas (GUACA) covers altitudes from 0 to27 profile. Tabulations ofwind speed, pressure,
km(Ruth etal., 1993). Altitudesfrom 20 to 120 kmare temperature, density, water vapor pressure, virtual
represented bydata from MiddleAtmosphere Program temperature, and dewpointtemperature at1km
(MAP) (Labitzke et al., 1985), and regionsabove 90 km intervalscomprising theKRA, as well as detailsofthe
are simulated bytheJacchia model (Jacchia, 1970). interpolationstothevertical grid,additional analysis,
GRAM-99 employs afairing procedure to ensure a anddocumentation arepresented intheRawlins and
smooth transitionfrom onedata settothe nextin Johnson (2000) report.
regionswhere thedata setsoverlap. The model also Climatological data for Kodiak used inthe
allowsfor use ofthenewer Global Gridded UpperAir atmospheric "mission analysis" aretaken fromthe
Statistics (GGUAS) data inthelower altitude regionin standard (historical) hourlysurface weather
place oftheGUACA data set. For detailsofGRAM-99, observations. Data utilized inthisstudyaredrawn from
theGUACA data, andthe GGUAS the reader isreferred the period1970-1998. Froma total of39 available
toJustus andJohnson (1999). weather parameters, cloudceiling height, totalsky
A new feature ofGRAM-99 istheoptiontouse data cover, visibility,occurrence ofthunderstorms, and
from aset ofRange Reference Atmospheres occurrence ofprecipitation provide the5 inputsused to
(Meteorology Group Range Commanders Council, illustratethe importance ofanatmospheric mission
1983) as an alternate totheGRAM data for aflight analysis inaerospace programs.
profilenear a particular range. Beginning in1963, a
seriesoftechnical documents characterizing wind 5. Atmospheric environment of Kodiak, AK
components and atmospheric thermodynamics were
produced for a numberof launchsitesbothin theUnited Wind
States andabroad. Derived from thebestavailable Mean windspeeds tabulated inthe KRA are
upperatmosphere data from rawinsondes and examined to characterize the general vertical and
rocketsondes, the Range Reference Atmospheres seasonal distributionfrom the surface through30 km.
containtabulations ofmonthlyand annual means, Speeds are greatest atapproximately 10 kmwithmean
standard deviations, andskewness coefficientsfor wind values beingover 25 rn/s(Figure 1),although mean
andatmospheric thermodynamics from thesurface to windscan readily exceed 70 m/s inmore intense
30 km, orsurfaceto as highas 70 kmwhen data from storms. Winds are generally lightinsummer,
rocketsondes were available. Skewness isa measure particularly between 20-25 km. Examination ofthe U
ofthe lackofsymmetry ina probabilitydistribution. For and Vcomponents (Figure notshown) reveals winds to
example, anormal distribution haszero skewness, and be generallywest-southwesterly during much ofthe
alognormaldistributionispositively"skewed". Inorder year, however bothzonal and meridional windsare very
to maintain a level ofstandardization, themodeling light(< 10 m/s) insummer. Zonal winds are typically
code, publicationtext andtable format for each Range westerly, witheasterly winds insummer between 22 and
Reference Atmosphere was tobe identical. To maintain 30 km, andbelow 5 km.
consistency, the Rawlins andJohnson (2000) document Differences between windcomponents intheKRA
contains tabulations andstatisticsthat mirrorthese andthose represented inGRAM-99, illustratethe
documents. accuracy ofthe GRAM model. Ucomponent
differences are small, onlyexceeding 4 m/s between 12
and22 km inDecember (Figure 2), withmostdeviations
lessthan 2 m/s. Differences intheV components
+
Mean Wind Speed at Kodiak, AK RLL, - , + , . , , r_ ' - 1 r 1 , ,
wind speed in m/s
-1+-12-10 4 -4 -4 -2 0 l 4 S 8 10
o !.I.".+..+"1
o_d(_-Og forOv_
2 3 4 5 6 7 9 10 11 12
Mont_
Figure 1. Mean windspeed at Kodiak, AK.
-1+-12-10 -8 _ -4 -_ 0 l 4 _ S 10
U Component Difference between KRA and GRAM-99
+, V.,)°
-14-12-10-e --_ -4 -2 o 2 4 _ 6 _o
Figure 3. Airtemperature differences between the
KRA, U.S. Standard Atmosphere, and GRAM-99 for
I l :i 4 6 o 7 I o Io 11 12 January, July,and Annual mean temperatures.
M_._th
V Component Difference between KRA and GRAM-g9 Monthly Mean Temperature D_fference between KRA and GRAM-99
I t,
t 2 3 4 5 IO 7 8 II I0 11 12
Monnthegat_ diffenl_Atl (m/l) it1doIh41_ I_,e_ + z .] + + i+ + a l m 11 ;z
momt_ neQoli._ diffem+m I (K) i+ d_lh+d li_l
Figure 2. Wind component differences between the
Figure 4. Differences inmean monthlytemperature
KRA andGRAM-99. Differences (m/s) aredefined as
between theKRA and GRAM-99.
KRA value minusGRAM-99.
Standard Atmosphere are substantial, particularly when
(which are considerably lowerthan the U components)
comparing January temperatures below 10 km where,
are generally less than 1.5 m/s.
as one might expect, the KRA temperatures are 6-15 K
colder (Figure 3). January temperatures in the 10-20
Air Temperature
km region are relatively warmer than the U. S. Standard
Forover 40 years,the U. S. Standard Atmosphere
Atmosphere, owing inpart to the shallow depth of the
has been thebenchmark definition ofthemidlatitude
troposphere at higher latitudes. This fact isevident in
atmosphere for theaerospace industry. With the
July temperatures as well, with KRA values 6 Kwarmer
development oftheGlobal Reference Atmospheric
than the Standard Atmosphere above 10 km. Asimilar
Model (JustusandJohnson, 1999) engineers havebeen
pattern is also evident inannual temperatures.
abletoassess seasonal and geographic variabilityfor
GRAM-99 estimates of air temperature at Kodiak are
locationswhere theU. S.Standard Atmosphere may not
in much better agreement with the KRA values (Figures
besufficientlyaccurate. Indeed differences inair
3and 4)than the KRA/U. S. Standard Atmosphere
temperature between thenew KRA andthe U.S.
comparisons. Differences are less than +/- 2 Kfrom the
surface to26 km inboth January and July, withthe KRA
estimates being slightly colder. Annual temperatures
are invery close agreement; differences are small
through most ofthe profile. Across all months,
deviations are generally less than +/- 1K, with the
exception of altitudes above 27 km, where the KRA
estimate are 2-4 Kcolder than the GRAM-99
0.01 0.O3 o.O3 0.O4 O.05
representations (Figure 4).
Coef,tlckl_ _ V_tk, n f_ 0w'm_
Density
Atmospheric density isone of the more important
inputs interrestrial environment definitions for
aerospace applications. Density affects flight
performance, aerodynamic heating, and vehicle load
stresses to name a few. Variability indensity can be
0 0.0_ O.02 O.O3 O.04 O.05
illustrated through the coefficient of variation, defined as C.o_t_m,¢ at ,,l_lt,on
the standard deviation divided bythe mean. For 1-km
densities derived and tabulated inthe new KRA,
minimum variability inJanuary density occurs at 2-3 km,
which is referred to as the isopycnic level, while a
maximum is found at 11 km (Figure 5). In July abroad
minimum occurs from the surface to 10 km and like |
January, the maximum is near 11 km. As one might
expect, the coefficient of variation is larger for annual 0.01 0.02 O.O3 0.O4 O.05 O.05
density, sincethe means and standard deviations are
determined from allderived densities at agiven altitude
Figure 5. Coefficient ofvariationfor January, July,
over the year. andAnnual mean density.
Density differences between the KRA and U.S.
Standard Atmosphere, as was the case with air
temperature differences, are relatively large (Figure 6).
Fordensity we define the differences inpercent, relative
to the KRA densities. InJanuary KRA density is less
than the U.S. Standard Atmosphere value through most
of the profile (due to awarmer layer inthe U. S.
Standard Atmosphere), exceeding 6% difference from
10-20 km. Deviations are smaller inJuly, with percent
differences greater than 4% between 20-27 km only. -10-I-e-7-8-_-4-3-2-I 0 I 2 3 4 s
Annual density differences, like those inJanuary, are
non-trivial; KRA density is less than the U.S. Standard
Atmosphere by greater than 5% from 10-16 km, and
again between 27-30 km.
Comparisons between the KRA and GRAM-99
reveal veryclose agreement inmostcases. Differences
are within 1%through most of the January, July and
annual profiles (Figure 6), with differences exceeding -*O-g-8-7-a-_-¢-3-2-1 0 1 I I 4 5
om_y ¢_e_t a_m
1%above 26 km in January and above 28 km for
annual density. Over all months, percent differences
are again small, exceeding 1% at afew altitudes/months
(Figure 7). Itis apparent that the GRAM-99 depiction of
atmospheric density at Kodiak is invery good
agreement with the historical twice-daily rawinsonde
observations used to create the KRA.
6. Surface Climatological Analysis
Figure 6. Density differences between KRA, U.S.
Terrestrial environment factors, ormore specifically Standard Atmosphere, and GRAM-99 forJanuary, July,
weather-related variables, can have agreat impact on and Annualmean density.
the probability of achieving asuccessful launch.
Characterization of the surface environment is also vital
inthe design phase of a new launch vehicle. Most are made for single parameters or acombination ofa
statistical summaries of weather- related variables few variables. However, interest is not only in the
Density Percent D(iKffeRrenAc-eGRbeAtwMeenO/gK)KRRAAand GRAM-99
Table 1.
hr J F M A M J J A S O N D
LST
NOGO Probabilities inpercent
0 78 78 72 78 79 81 77 75 76 69 69 74
1 77 76 73 77 78 80 78 76 76 69 71 74
2 84 85 81 84 83 82 82 80 81 77 81 81
3 78 75 73 76 78 81 79 76 75 68 73 77
4 79 76 73 79 77 81 78 74 74 65 73 76
5 84 83 80 78 79 79 81 74 76 74 80 83
6 77 74 72 80 78 84 81 76 71 66 72 76
O" _0 'O
7 75 72 68 77 78 83 80 76 74 63 69 74
1 2 _ 4 _ _ 7 S O 1D 11 J2 8 76 71 69 77 80 81 80 74 75 66 68 72
Month negotlveperce_togeminOash_ _inea 9 72 69 68 77 79 86 81 73 74 63 66 71
10 73 72 68 78 80 86 81 73 73 64 66 72
Figure 7. Percent density difference between KRA and 11 75 71 67 77 81 81 81 74 73 66 67 71
GRAM-99. Difference is KRA minus GRAM-99 divided 12 76 69 66 76 81 85 81 75 74 65 66 73
13 76 72 67 77 80 84 81 76 75 68 66 74
by KRA value * 100.
14 75 71 69 76 82 79 79 76 75 70 68 73
15 76 69 68 76 78 82 79 77 75 68 68 76
16 77 70 68 76 78 82 79 77 75 68 67 75
probability of occurrence for each of the individual 17 77 71 68 75 79 77 77 76 76 71 70 79
events taken separately but also in the chance that at 18 74 71 69 75 77 79 79 75 77 67 67 77
least one of those events will occur during any particular 19 75 73 68 74 77 80 80 74 75 68 69 77
phase of the mission (Johnson, et al., 1997). For 20 81 80 77 76 78 75 79 73 78 77 77 84
example, there may be constraints due to several 21 76 74 69 76 76 79 79 72 73 72 70 77
22 78 75 69 75 76 78 79 73 73 71 70 77
environmental parameters, with the occurrence of any
23 84 83 79 82 81 78 81 79 78 76 77 82
one of the conditions constituting a "No-Go" situation.
An atmospheric "mission analysis" isoften used to
Overall percent average = 75.4
answer questions such as a) what is the probability that
a particular event will (will not) occur during a given
reference period, b) what is the probability that a
particular event will (will not) occur for Nconsecutive Table 2.
days during a given reference period, and c) once a
designated condition has (has not) occurred for N hr J F M A M J J A S O N D
consecutive days at a particular time of day, what is the LST
probability that the given condition will continue for N NOGO Probabilities in percent
additional days (Johnson, et al., 1997). 0 57 54 52 59 59 63 60 49 49 41 45 54
1 55 56 51 58 60 65 61 50 51 41 46 54
An atmospheric mission analysis for Kodiak was
2 58 57 51 58 62 61 60 52 51 44 48 52
performed using hourly surface weather data for the
3 56 54 51 58 60 66 61 50 50 41 46 54
period 1970-1996. To illustrate the effect on Go-NoGo 4 57 56 51 60 61 68 61 51 49 40 49 54
probabilities, the mission analysis was run for two 5 60 56 51 56 62 64 63 53 49 43 45 52
relatively disparate sets of constraints. In both cases no 6 59 54 50 61 62 68 61 53 49 41 47 54
thunderstorms or precipitation was allowed. For case 1, 7 56 53 50 60 62 69 62 53 51 40 46 53
visibility cannot be < 10 nautical miles, cloud ceiling < 8 56 57 52 60 65 65 64 54 53 45 48 52
10,000 feet, or total sky cover >0.5. In case 2, a very 9 54 56 53 60 62 71 61 48 50 42 48 53
liberal set of constraints was set. Visibility was relaxed, 10 54 59 51 61 60 68 61 49 50 43 48 55
11 57 58 51 58 62 63 59 51 50 45 48 56
and cannot be to < 1 nautical mile, cloud ceiling <2,000
12 56 55 51 58 61 67 58 45 48 43 47 56
feet or total sky cover > 0.9. Tables 1 and 2 list the 13 57 54 51 55 59 65 56 46 47 43 47 56
probabilities that at least one of the constraints will 14 58 54 51 55 60 59 56 48 47 47 50 56
occur, listed by hour and month, based on empirical 15 56 54 52 57 56 62 55 46 46 45 52 60
data for the period 1970-1996. For case 1, No-Go 16 57 55 52 55 55 60 56 47 46 46 50 61
conditions were present 75.4% of the time (on average), 17 58 57 50 55 58 57 56 49 49 49 49 59
with late morning hours during summer being the most 18 57 55 52 57 56 61 56 48 47 49 48 61
19 58 56 52 57 57 61 59 47 46 47 48 59
challenging launch environment. No-Go probabilities
20 59 55 52 58 60 56 58 50 49 47 48 56
are significantly decreased for the more relaxed set of
21 56 54 54 60 59 61 59 49 49 45 48 57
meteorological conditions (Case 2); sufficient conditions 22 57 54 53 60 61 63 61 49 49 46 46 58
are met an average of 54.2% of the time. Early morning 23 59 53 53 57 62 60 60 52 48 44 46 52
hours in autumn provide the best opportunity for launch,
with average probabilities of just over 40% (Table 2). Overall percent average = 54.2
Examination of the individual meteorological parameter
probabilities (Tables not shown) indicates that visibility
is the most sensitive parameter. Requiringaminimum Alabama inHuntsville; O. E. Smith, Stanley I.Adelfang
visibilityof10 nautical milescauses a No-Go probability and Carl G.Justus, Computer Sciences Corporation.
ofapproximately 35% (averaged over all hours/months).
Byrelaxing visibilitytoaminimum of 1nauticalmile, No- References
Go probabilities from thevisibilityconstraint arereduced
toanaverage of 1%. Cloud ceilingisthenextmost Adelfang, S. I., O. E. Smith andG. W. Batts, (1994):
sensitiveconstraint;average No-Go probabilities are "Ascent Wind Modelfor Launch Vehicle Design",
nearly halved when requiringa2,000 feet ceilingversus Journal of Spacecraft and Rockets, Vol. 31, number 3,
themore stringent 10,000 feet requirement. Totalsky pp.502-508, May-June
cover has thesmallestimpact on probabilities. Itshould
be noted thattheconstraints incase 1should notbe COESA, (1962): "U. S. Standard Atmosphere, 1962",
considered unreasonable for mostlaunch vehicles. But U.S. PrintingOffice, Washington, D.C., 278 pp.
regardless ofthepreciseenvironmental constraints
imposed, Kodiak Island,Alaska isclearly achallenging Jacchia, L.G., (1970): "New Static Models ofthe
environment for missionsuccess, particularly during Thermosphere and Exosphere withEmpirical
morninghoursinsummer months. Temperature Profiles",Smithsonian Astrophysical
Observatory, Special Report 313
7. Summary Remarks
Johnson, D.L., S. D.Pearson, W. W. Vaughan, G. W.
Launch vehicledesign and operation aredependent Batts,(1997): "Role ofAerospace Meteorology inthe
on accurate definitions oftheterrestrial environmentfor Design, Development, andOperation ofNew Advanced
mission success. A new reference atmosphere for Launch Vehicles", Seventh Conference onAviation,
Kodiak, Alaska hasbeen developed fromhistorical Range, and Aerospace Meteorology, 2-7 February
rawinsonde observations and compared tothe U.S.
Standard Atmosphere and GRAM-99. Substantial Justus, C.G. and D. L.Johnson, (1999): 'qhe
disparity isnoted between theKodiak Reference NASA/MSFC Global Reference Atmosphere Model-
Atmosphere (KRA) and theU. S. Standard Atmosphere, 1999 Version (GRAM-99)", NASA TM-1999-209630,
which wasdeveloped to represent atypicalmidlatitude May
environment. Excellentagreement isevidentbetween
the KRAand GRAM-99 for windcomponents, air Labitzke, K., J.J. Barnett, B.Edwards, (1999): "Middle
temperature and density,particularlybelow 25 km Atmosphere Program -Atmospheric Structure and its
where the GRAM model primarily utilizestheGUACA Variation inthe Region 20 to 120 km -Draft of a New
database. Reference Middle Atmosphere", Handbook for MAP,
Analysis ofGo-NoGo probabilitiesdueto launch Vol. 16, 318 pp., July.
weather constraintsreveals relatively high No-Go
probabilities when usingtypicalmeteorological Meteorology Group Range Commanders Council,
requirements. Probabilitiesofencountering adverse (1983): "Range Reference Atmosphere", Published by
weather conditions byhourand monthcan begreater Secretariat Range Commanders Council, White Sands
than 75% for the typicalrequirements, suggesting that Missile Range, New Mexico, 88002
careful launchscheduling maybe prudent toavoid
costlydelays. Hourlyweather data used inthe NASA (1999): "NASA Awards Launch Contract for
atmospheric missionanalysis wasgathered atKodiak Athena Rocket", Kennedy Space Center Press Release
City,AK, whichisapproximately 40 miles northofthe No. 30-99
Kodiak Launch Complex at NarrowCape. Itispossible
that adverse weather conditions(lowclouds,fog) atthe Pearson, S. D., W. W. Vaughan, G. W. Batts,and G. L.
launch site maybeworse than thestatisticsindicate, Jasper, (1996): "Importance oftheNatural Terrestrial
depending ontheprevailing winddirection. Environment With Regard to Advanced Launch Vehicle
Rocketsonde data previously has been used to Design and Development", NASA TM-108511, June
estimate winds and atmospheric thermodynamics above
typicalrawinsonde ascents. However, noneexistsfor Rawlins, M. A. and D.L.Johnson, (2000): "Reference
Kodiak. Incorporationofsatellite estimates, nearby Atmosphere for Kodiak Island, Alaska", NASA Technical
rocketsonde data orotherrepresentative information Report (in preparation)
may prove usefulinthefuture. A comprehensive report
detailing theKodiak Reference Atrmosphere, the Ruth, D. B.,(1993): "Global Upper AirClimatic Atlas
surface environment, andadditional descriptions and (GUACA)", CDROM data set Version 1.0, US Navy - U.
analysis isbeing planned for use infuture launch S. Department ofCommerce (NOANNCDC), April
vehicledesigns and/or operations.
U.S. Standard Atmosphere, (1976): Prepared underthe
Acknowledgements sponsorshipofthe National Aeronautics and Space
Administration, United States AirForce, and United
The authors wishto acknowledge frequent and useful StatesWeather Bureau, Available throughU. S.
discussionswithWilliam W. Vaughan, Universityof Government PrintingOffice, Washington, D.C., October