Initial Sizing InputsShare -ware !Simplified Aircraft Design
Spreadsheet for HomebuildersEnter items in blue and purple. Come
back and re-enter purple items after the drawing is
analyzed.Version 1.0 Copyright C 2003 by Daniel P. Raymer. All
Rights Reserved. See legal notice for further restrictions.LEGAL
NOTICE !Better to save this spreadsheet as a renamed copy before
changing it for your airplane, in case it gets messed up!Send
problems & questions to [email protected]
LoadingInputsCalculated ValuesOther Factors UsedEquations (from
book)Misc Useful CalcsStall speed(kts)60Stall speed(ft/sec)101.3(OK
to change these if you know what you are doing)Takeoff air
density(slugs/ft^3)0.00238Dynamic pressure(psf)12.2Wing
CLmax1.6Wing loading (W/S)(psf)19.55power loading(lb/hp)8.3333Wo
-known engineIf sizing to a range requirement, ignore this input
for now but enter it later when Wo is calculated and engine is
selectedYou cannot enter Wo! Engine power and power loading are
multiplied to calculate Wo. If sizing to a range requirement, do
calculation below, read Wo from graph, and select an engine that
gives the desired Wo=P*P/WEngine Power(hp
-each)120Wo(lb)2000.0Number of Engines2Wing Area(sq ft)102.3Wo
Sizing to a range requirement (engine is not yet
selected)Swet/Sref4.2Cfe0.0053Cdo0.0223Aspect ratio (A)10K
(=1/piAe)0.0424e (Oswald)0.75Cruise air
density(slugs/ft^3)0.00176W/S cruise19.2Wcruise/Wo0.98Cruise
velocity(kts)180Cruise
velocity(ft/sec)304.0CL-cruise0.2355959596Dynamic
pressure(psf)81.3L/D cruise9.57Engine SFC(lb/hour /bhp)0.45Engine
SFC(lb/sec /bhp)0.000125Prop Efficiency
(cruise)0.75Range(nmi)800Range(ft)4860800Breguet
Exponent0.1539Wf/Wo0.1641Non-cruise weight allowance0.975Fuel
allowance(%)6Wf/Wo with allow.0.1739Empty Weight constant
"a"1.2438Empty Weight exponent-0.09Fuel Weight347.8(lbs)Weight -
crew(lbs)180Fuel Vol58.0(gal)Weight - Passengers(lbs)180Weight -
payload(lbs)20See Sizing Graph sheet for Wo ResultsWing
GeometryWing taper ratio0.5Wing Span(ft)31.98Root Chord(ft)4.26Tip
Chord(ft)2.13Mean Chord(ft)3.32Tail SizingHorizontal tail
arm(ft)10Tail areas:Preliminary tail sizing using these methods
does not guarantee that the aircraft will be stable, controllable,
or safe. You must perform stability calculations after doing your
design layout!Cht (volume coeff)0.6Sht (horizontal)(sq
ft)20.35Vertical tail arm(ft)10Cvt (volume coeff)0.04Svt
(vertical)(sq ft)13.08
If you really want to use a particular engine, and you really
want a particular Wo, you must cheat! Calculate power loading
(W/hp) from these values and enter it and the horsepower of your
engine. This should give you the Wo you want. However, you should
check the performance calculations because the results may not be
what you want!including landing gear drag if not retractableBased
on the methods, definitions, and equations in Dan Raymer's
Simplified Aircraft Design for Homebuilders, Design Dimension
Press, Los Angeles, 2003. For ordering information please visit
http://www.aircraftdesign.comTHIS SPREADSHEET IS NOT FREEWARE! See
legal notice in red box.THIS SPREADSHEET IS NOT FREEWARE! It is
provided free of charge ONLY to original purchasers of the book Dan
Raymer's Simplified Aircraft Design for Homebuilders. Others
wanting to use it LEGALLY must send $25 to: Design Dimension Press
PO Box 923156 Sylmar, CA 91392-3156, USA (CA residents add $2 for
sales taxes)For information about school licenses please contact
the author at [email protected]. This spreadsheet may NOT
be modified or edited (other than to input data for your airplane),
nor incorporated in any other spreadsheet or program, without the
written permission of the author.
LICENSE AGREEMENT AND DISCLAIMER OF WARRANTY:
This Simplified Aircraft Design spreadsheet is COPYRIGHT (C)
2003 by DANIEL P. RAYMER. ALL RIGHTS RESERVED. No part of this
spreadsheet software may be reproduced, distributed, or
transmitted, in any form or by any means, or stored in a database
retrieval system, without prior written permission of Daniel P.
Raymer.
This license agreement replaces and supersedes any and all other
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(Design Dimension Press is a subsidiary of Conceptual Research
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statements above)
Sizing GraphSizing CalculationsWo guessWe/WoWeWo
calculated10000.6680668.02403.215000.6440966.02087.320000.62761255.11914.225000.61511537.71801.0Pick
Wo from graph, where the two lines cross. Enter this value below to
find the minimum horsepower engine for your power loading.If sizing
graph lines do not cross, change Wo-guess values above.Enter Wo
from graph(lbs)2000Pick engine with horsepower of at least:120Now
find a suitable engine of at least this horsepower and enter its
power below:Power of Selected Engine:120Calculated Power
Loading:8.33Now go to sheet 1 and enter the power of your selected
engine and the power loading calculated above in the boxes this
color.
Sizing
Graph2403.245643491210002087.278763920615001914.204415092420001801.00340513612500
Wo GuessWo CalculatedSizing Graph
As-Drawn PerformanceAs-Drawn Performance Calculations for
Simplified Aircraft Design for HomebuildersUse this sheet for
performance calculations after you have drawn your design and
measured its geometry.Values from Sheet 1 - OK to change these
here, but then link from Sheet 1 is lostCalculated ValuesEquations
(from book)Wo(lb)2000wing loading (W/S)(psf)19.55Engine
Power(hp)120stall speed(ft/sec)101.34Number of Engines2stall
speed(kts)60.00Engine SFC(lb/hour /bhp)0.45power
loading(lb/hp)8.33Wing Area(sq ft)102.3Takeoff
Parameter123.2Cdo0.0223Takeoff Groundroll(ft)874.2K
(=1/piAe)0.0424Takeoff to 50 ft(ft)1159.1Wing CLmax1.6Takeoff air
density(slugs/ft^3)0.00238e (Oswald)0.75Wcruise/Wo0.98Cruise
Weight(lb)1959.99216Non-cruise weight allowance0.975Fuel
allowance(%)6Weight - crew(lbs)180Weight - passengers(lbs)180Weight
- payload(lbs)20Empty Weight(lbs)1255.1Other InputsPropeller
Diameter(ft)5Engine RPM(rev/min)2700Cooling Power Loss(%)6Cruise
Power Setting(% of SL hp)62Cruise air
density(slug/ft^3)0.00176Power Coefficient Cp0.1317Go to next sheet
for climb, cruise, and maximum speed calculations then return
hereCruise speed(kts)180Cruise speed(ft/sec)304.02Cruise Advance
Ratio J1.3512Cruise Prop efficiency0.85Cruise q(psf)81.3Cruise
W/S(psf)19.2Cruise L/D9.6Wfuel (total)(lbs)365Wfuel
(usable)(lbs)344Wfuel (cruise)(lbs)294log
term1.1776908892Range(ft)5854552Range(nmi)964
Uses straight-line approximation of takeoff parameter chart in
bookYou should change this approximate empty weight value to match
your group weight calculations. Or, you can change the empty weight
constant "a" value on the first sheet so that this box produces the
empty weight you calculated. This allows you to resize your design
if you wish using a "calibrated" We/Wo equation.As found from chart
on next sheet
Climb, Cruise, & Max SpeedClimb, Cruise, & Max Speed
Calculations for Simplified Aircraft Design for HomebuildersUse
this sheet for performance calculations after you have drawn your
design and measured its geometry.Input adjusted valuesEquations
(from book)V ktsV ft/secAdvance Ratio JPropeller EfficiencyTotal
Thrust lbsCruise Thrust lbsDynamic pressure qCLCDDrag lbsClimb
(fps)5084.450.37533333330.59866.8703374778537.45960923626.27598623.11563636360.4342331415278.7433152541520.4344601092100168.90.75066666670.8587.7087033748364.379396092425.10394480.77890909090.0480083213123.27017329882401.3463726253150253.351.1260.85416.2936648905258.102072232156.48387580.34618181820.0273460882157.98622195632003.3403807298200337.81.50133333330.82301.2007104796186.7444404973100.41577920.19472727270.0238692701245.1549212659579.5615303804220371.581.65146666670.8267.1403197158165.6269982238121.5030928320.16093163040.0233591531290.2979312743-263.4165221221Read
Cruise speed where cruise thrust line crosses drag line and enter
in cruise speed box (this color) on previous sheet
Using Power Coefficient from Sheet 3. Include adjustments for
scrubbing drag and other propeller losses (see book).
Climb, Cruise, & Max
Speed866.8703374778537.4596092362278.743315254587.7087033748364.3793960924123.2701732988416.2936648905258.1020722321157.9862219563301.2007104796186.7444404973245.1549212659267.1403197158165.6269982238290.2979312743
Total ThrustCruise ThrustDragVelocity - ktsThrust or Drag
-lbsMaximum & Cruise Speed
WeightSheet1520.43446010922401.34637262532003.3403807298579.5615303804-263.4165221221
Velocity - ktsClimb - fpmRate of Climb - Sea Level
A-optWeight Reporting Format for Simplified Aircraft Design for
HomebuildersUse this sheet for reporting weights calculations &
estimating center of gravity.Input only items in blue(Sorry, no
weights estimation methods here, just the form to enter your
estimates. Moments & cg are
calculated)WeightLocMomentWeightLocMomentlbsftft-lbslbsftft-lbsSTRUCTURES661.05600EQUIPMENT69.0429Wing2766.51794Flight
Controls105.555Horizontal Tail2421.0504Instruments105.555Vertical
Tail1819.0342Hydraulics26.012Ventral
Tail817.0136Electrical126.072Fuselage1559.01395Avionics155.075Canopy158.0120Air
Conditioning0Nacelle on
wing509.0450Anti-Icing0Nacelle/cowling307.5225Furnishings &
Equipment208.0160Motor Mount107.575Main Landing Gear569.0504(% We
Allowance)10enter %Nose Landing Gear192.955Empty Weight
Allowance114.17.8891dont enter thesePROPULSION411.02877TOTAL WEIGHT
EMPTY1255.17.89797Calculated Empty Weight constant "a". Go to
Initial Sizing Inputs sheet and revise value in purple
box:1.2438Engine3407.02380Air Induction37.021USEFUL
LOAD744.9Cooling37.021Crew180.08.01440Exhaust87.056Fuel358.97.52692Don't
enter this! It is calculated from Wo, We, and other Useful Load
Group itemsEngine Controls27.014Oil65.030Misc. Engine
Inst57.035Passengers1808.01440Propeller307.0210Payload2010.0200Starter107.070Fuel
System107.070TAKEOFF GROSS WEIGHT2000.07.815598Possible Loading
ConditionsCrew+Pass+Pld, No Fuel1641.17.912907Crew+Pass,No Pld,No
Fuel1621.17.812707Crew only, No Fuel1441.17.811267Crew only, Full
Fuel1800.07.813958
If these velocities are too slow or too fast you can change
them, but you must have only 5 velocitiesAt takeoff weight WoFrom
Sizing Inputs Sheet - OK to change but then link is lostFrom Sizing
Inputs Sheet - OK to change but then link is lostFrom Sizing Inputs
Sheet - OK to change but then link is lost
ASPECT RATIO OPTIMIZATION:
DR-4A-baseline10Wo2000.0Wwing-base276We-base1255.1Read performance
results and enter hereAA/AbaseWwing/ Ww-baseDelta WeWe-newRangeMax
SpeedCruise
SpeedROCmax*10cruise*1060.600.74-7311821165212175220021201750101.001.0001255964220180240022001800141.401.22621317760221181250022101810Enter
delta on Weight sheet (I stuck it in the unused Anti-Ice entry),
and change aspect ratio and empty weight "a" factor on Initial
Sizing Sheet
1165212017502200964220018002400760221018102500
RangeMax Speed *10Cruise Speed *10Rate of ClimbAspect Rationmi,
kts, or fpmAspect Ratio Trade Study
MBD000AE140.unknown
MBD000AE64C.unknown
MBD000B58E9.unknown
MBD000AE44D.unknown
MBD00022254.unknown
MBD000551C9.unknown
MBD0007D92E.unknown
MBD0003D561.unknown
MBD0004BC4A.unknown
MBD00027BBD.unknown
MBD000103D8.unknown
MBD00010751.unknown
MBD0000E884.unknown
MBD0000EB55.unknown
MBD000052FA.unknown
