lockheed aircraft corp.

Transcription

lockheed aircraft corp.
Analysis Range
Prepared by C.L. Johnson
Date June 4, 1936
Page
Model
LOCKHEED AIRCRAFT CORP.
*****************************************************
of Pages
No. of
FORM 100
– 37
Photographs – 0
By –
10E
Report No
RANGE STUDY OF LOCKHEED ELECTRA BIMOTOR AIRPLANE.
No.
0
C.L. Johnson
W.C. Nelson
487
Analysis Range
Prepared by C.L. Johnson
Date June 19, 1936
LOCKHEED AIRCRAFT CORP.
Page
00
Model
10E
Report No
INDEX.
******
ITEM
FORM 100
PAGES.
Face page
0
Index
00
Introduction
1
Summary and recommendations
1 –4
Discussion
3
Discussion of curves derived
4–5
Additional data
6
Conclusions
6
Flight procedure data
7
Effect of head and tail winds
8
Various curves on range performance
9 – 14
Take-off curves and effect of wing flaps
15
Normal airplane cruising charts
16
Engine power curves
17–18
Appendix and computaions
19 – 36.
487
Analysis Range
Prepared by C.L. Johnson
Date June 4, 1936
LOCKHEED AIRCRAFT CORP.
Page
1
Model
10E
Report No
487
INTRODUCTION.
*************
This report contains a complete study of the factors determining
the maximum practical range of the Lockheed Electra Model 10E bimotor airplane. The problem is gone into in considerable length in
order that complete recommendations may be made as to optimum methods
of take-off, climb and level flight. Such factors as the effect of
altitude, wind, variation of propulsive efficiency at constant forward speed, and variation of specific fuel consumption are all included in the study. As a summary, curves are given showing the
recommended values of the above throughout a flight of the greatest
possible range.
The airplane under consideration is a Model 10E Electra equipped
with Pratt and Whitney S3H1 engines rated 600 BHP at 2300 rpm for
take-off and not more than 412 BHP at 2000 rpm for cruising. To enable close control to be maintained over the mixture strength, a
Cambridge gas analyzer is connected into the exhaust system. Hamilton Standard constant rpm, controllable pitch propellers are used.
Added to this equipment is a Sperry Gyro-Pilot to lessen fatigue during long flights.
The engine operating conditions have been given careful consideration in recommending a flight procedure. Combinations of rpm and
manifold pressure are chosen with regard to engine reliability and
smoothness as well as optimum propulsive efficiency.
SUMMARY AND RECOMMENDATIONS.
*****************************************
The complete performance has been computed conservatively
based on actual flight test results on Model 10E*. Fuel consumption
data is based on results which have been obtained in flight with
careful mixture control. To get a range of 4500 miles it will be
necessary to calibrate the Cambridge Analyzer so that the fuel consumption curve shown on page 13 can be obtained.
FORM 100
Analysis Range
Prepared by C.L. Johnson
LOCKHEED AIRCRAFT CORP.
Date June 14, 1936
Page
2
Model
10E
Report No
SUMMARY AND RECOMMENDATIONS.
*****************************************
The important results from the report may be summarized as
follows:
(1). Best take–off distance is obtained using a 30° wing flap
setting. The tail of the airplane should be lifted off
the ground as soon as possible and held up through the
take–off run.
(2). On a hard run–way, using 600 BHP per engine, the take-off
distance is 2100 feet at sea level.
(3). Climb after take-off with a gross weight of 16,500# is 500
feet per minute with wing flaps at 30° (using take-off power).
(4). After obtaining a safe altitude (50 to 100 feet), the flaps
should be retracted and the engine power reduced to 550 BHP
per engine at 2200 rpm.
(5). The climb should be continued at this power to an altitude of
2000'.
(6). At 2000', the power should be reduced to 380 BHP/engine and
the flight continued at the values of altitude, power, rpm and
speed shown on the inclosed curve.
(7). During the maximum range flight, the following considerations
apply:
FORM 100
a.
Variation of altitude from that specified by amounts
as much as 2000' (except in the heavy load condition) has
very little effect on the range.
b.
With headwinds or tails winds up to 20 mph, the best
airspeed is wthin 5 mph of that shown on the flight
procedure curve.
c.
When the wind increases with altitude, the load
condition, and power conditions should be carefully
considered when choosing an altitude different than
that shown on the curves. No strict rules can be given
covering the optimum flight procedure with varying
wind gradients with altitude.
d.
Increase the power output when climbing from one altitude to another. Climb at an indicated speed of 120
to 130 mph.
487
Analysis Range
Page
Prepared by C.L. Johnson
LOCKHEED AIRCRAFT CORP.
Date June 16, 1936
3
Model 10E
Report No
487
SUMMARY AND RECOMMENDATIONS.
******************************
Continuing the di scuss ion of important factors during the
maximum range f l ight –
e. Watch the mixture closely at all times. The engines must
be run very lean.
f.
In climb when the power output is increased, check the
mixture and head temperatures.
g. When about 100 to 150 miles from the end of the flight,
put the ship in a power glide losing about 250 to 300
feet of altitude per minutes while maintaining cruising
power output.
h. The best average altitude at which to fly and the best
power output are shown on the flight procedure curve.
The lighter the load, the higher the density altitude
for best range.
i.
Standard carburetor air temperature has been assumed in
choosing manifold pressures and rpm to obtain a given
power. Normal deviations of carburetor air temperature
likely to be encoucntered may be neglected.
j.
If icing conditions are encountered, so that carbu retor
heat must be applied, the mixture may have to be richened
somewhat to prevent detonation in the engines. Normally,
the carburetor heat should be set to “FULL COLD”.
DISCUSSION.
***********
The computations and most of the basic curves are given in an
attached appendix. In attacking the problem, complete calculations
of the altitude–speed–power characteristics of the airplane with
three different gross weights were made to get the optimum operating
conditions. Most of the final curves are derived using graphical in–
tegration of the basic curves.
Methods of computation are given in the Appendix and no further
discussion on procedure will be given here. Perhaps the simplest way
to give the results of the complete study is to comment on each of the
final curves presented.
FORM 100
Analysis Range
Page
Prepared by C.L. Johnson
Date June 16, 1936
LOCKHEED AIRCRAFT CORP.
4
Model 10E
Report No
487
DISCUSSION OF CURVES DERIVED.
***************************
The various c urves are denoted by f igure numbers at the bottom
of each sheet. The impor tant points about each f igure will be discussed
in tur n:
FIGURE I .
This is the curve sheet which summarizes the results of the
maximum range study. Star ting with a g ross weight of 16,500# (1200
gallons of fuel), the elapsed time and distance in air miles is
shown plotted against the optmum operating conditions of the airplane
and engine. This curve should g reatly simplify the pilot’s duties.
FIGURE II .
The ef fect of head winds and tail winds on the optimum f light
speed for a typical case is plotted. For a 20 mph head wind, the
indicated airspeed should be increased about 4 mph for the heavy load
conditioin. For the 20 mph tail wind, the speed should be decreased
about the same amount. Values for other load conditions and wind
speeds can be obtained from this char t. It applies exactly to sea level
only, but the trends shown apply fairly well to the range of altitudes
likely to be used.
FIGURE I I I .
The best speeds, power output and the elapsed time for the
longest range f light using the most conservative fuel consumption
curve is plotted against distance. This curve was modified and approx–
imated to get F igure I. It is interesting to note that over a fairly
wide range of power and speeds, the airplane e f f i c i e n c y is constant,
so that the same range can be obtained with considerable dif ference in
elapsed time. The f light procedure outlined in F igure I is based on
the lower power output at the beginning of the f light and the higher
power over the g reater par t of the f l ight so that a low elapsed time
can be obtained with the engine operating at its best ef f iciency and
reliability.
FIGURE IV .
Figure IV shows the variation of gross weight and best altitude
in the maximum range flight.
FORM 100
Analysis Range
Page
Prepared by C.L. Johnson
Date June 15, 1936
LOCKHEED AIRCRAFT CORP.
5
Model 10E
Report No
487
DISCUSSION OF CURVES DERIVED.
***************************
FIGURE V.
F igure V shows the ef f ect of a l t i tude and power output on the
air miles per gallon for the airplane at three d i f f erent g ross weights.
Neg lecting any wind g radient, it wil l be seen from the curves how
l i t t l e gain there i s in f ly ing at a high altitude over the major par t
o f the distance considered. With the highest g ross weight, there is
a def inite disadvantage in f lying higher than 2000’.
FIGURE VI.
This curve was derived to show the minimum amoun of fuel nec–
essar y to go various distances less than the maximum range. It also
shows the g ross weight with the above amount of fuel. In order to
increase the cr uising speed for distances less than the maximum, more
fuel than that shown wil l be taken along so that higher power outputs
may be used. This curve is based on the conservative fuel consumption
curve.
FIGURE VII.
F igure VII is a col l ect i on of various curves showing specif ic
fuel consumption, optimum power and weight conditions and the ef f ect
of g ross weight on best fuel consumption per mile. The fuel consumpt–
ion curves are average propeller load curves which apply to the aver–
age pitch settings of the propeller and throttle setting of the engine
during the f l ight. The higher curve has been refer red to as the “con–
servative curve”. The lower curve which reaches a minimum specif ic
fuel conssumption of .42 #/BHP/Hr. is the one which must be obtained
to get 4500 mile range.
The other curvse shown on F igure VII are self explanator y.
FIGURE VIII.
F igure VIII i s also a col l ecti on of curves used to derive the
best f light procedure. The decrease in miles per gallon with increased
g ross weight, and the corresponding increase in speed for best range
as the g ross weight is increased are ver y interesting.
FIGURE IX.
F igure IX gi ves the engine and propeller data for take–of f cal–
culations and the ef fect of f lap setting on take–of f distance at sea
level. The computations are based on having a good hard run–way and
using the best take–of f technique. The tail should be lif ted as soon as
possible for the minimum take–of f r un. The rate of climb af ter take–of f
is also shown for al l f lap settings.
FORM 100
Analysis Range
Page
Prepared by C. L. Johnson
Date June 16, 1936
LOCKHEED AIRCRAFT CORP.
6
Model
10E
Report No
ADDITIONAL DATA.
****************
Engine power curves of two types are included in Figures X and XI.
The normal cruising chart at the ATC gross weight is also furnished on
page 16. The increase in gross weight from 10,500# to the average weight
throughout the maximum range f l i ght (namely 12,900#) cuts dow n the high
speed to 200 mph at 10,000’ at 450 BHP output per engine. High speed at
sea level with a gross weight of 16,500# and 450 BHP/engine is 177 mph.
CONCLUSIONS.
************
As a result of the study just concluded,
are obtained:
(1).
the following results
It is possible to fly a Lockheed Electra Model 10E non–stop
for a distance between 4100 and 4500 miles starting out with
1200 gal lons of gasoline and the proper amount of oil.
(2). The above range is for zero wind conditions. The procedure
outlined in this report should be followed to get optimum
results. This is especially true in regard to maintaining
proper engine mixture control.
(3). The Cambridge Gas Analyzers should be carefully calibrated
in flight to see if the fuel consumption data used in this
analysi s can be obtained. This should be done before attempt–
ing any long range flight.
(4). The airspeed indicator must be c a l i b r a t e d for pitot–static
position error.
FORM 100
(5).
Low power output f l i ghts should be made with the leanest
mixture setting to be used to check the engine head temper–
atures. They may run too cool so that a shutter arrangement
might have to be made so that the head temperatures can be
kept up to the value giving best engine e f f i c i e n c y .
(6).
Do not draw more than 600 BHP for one minute on the take–off.
Cut back the power as soon as it is safe.
487
FORM 107
KEUFFEL & ESSER CO., N.Y.
NO. 359-14
Millimeters, 10th line heavy.
Initial gross wt: – 16,500#
Applies for Wind of ± 20 mph.
Take-off at 2300 rpm
and 36 1/2" for 1 minute
WATCH MIXTURE AT ALL TIMES.
2050
2000
2000
1950
1900
Range
analysis
C.L. Johnson
prepared by
date June 3, 1936
RECOMMENDED FLIGHT PROCEDURE
******************************
Lockheed Electra Model 10E.
Data for Obtaining Optimum Range.
Engine RPM
1800
400
360
1700
350
FIGURE I.
325
BHP/Engine
250
28.5"
LOCKHEED AIRCRAFT CORP.
380
200
28.5"
28"
26.2"
26"
24"
Average Manifold Pressure
21.5"
8000' – 135 M.P.H.
150 M.P.H.
4000' – 145 M.P.H.
DISTANCE – AIR MILES
0
0
1000
5
2000
10
15
APPROXIMATE TIME in HOURS
3000
20
4000
25
30
7
page
model 10E
report no. 487
Density Altitude and True
Indicated Airspeed.
2000' – 155 M.P.H INDICATED
FORM 107
KEUFFEL & ESSER CO., N.Y.
NO. 359-14
Millimeters, 10th line heavy.
analysis Range
prepared by C.L. Johnson
date June 3, 1936
EFFECT OF HEAD WINDS AND TAIL WI NDS
ON AI RSPEED FOR OPT IMUM RANGE.
Sea Level Al t i tude Shown — Simi l ar E f f ec t for Other Al t i tude s.
EXAMPLE:
70
To f i nd the optimum f l y i ng a i rspeed f or sea l evel with a gro ss weight
o f 16,500#, with any wind cond i t ion (head or ta i l wind), draw l i ne f rom wind speed
or i g in, tangent to the proper curve as shown.
40
30
20
For above example,
the best speeds are given below.
Zero wind
— 150 mph true airspeed.
20 mph ta i l wind — 146 mph.
20 mph head wind – 154 mph.
12,300#
9,300#
The above trends can be taken to apply f a i r l y well
the range of al t i t udes to be used.
20
h
mp
Ta
Ze
il
ro
Wi
nd
d
nd
Wi
20
h
mp
to
d
n
Wi
ea
H
Head Wind
Ta i l Wind
INDICATED AIRSPEED – M.P.H.
40
0
20
0
20
40
60
80
100
120
140
160
180
8
page
model 10E
report no. 487
10
Gross Wt. — 16,500#
Resul t s :
FUEL CONSUMPTION – GALLONS PER HOUR.
FIGURE II.
50
LOCKHEED AIRCRAFT CORP.
60
FORM 107
KEUFFEL & ESSER CO., N.Y.
NO. 359-14
12
M.P.H.
Hours.
Optimum Speed, Fuel Consumption, and Elapsed Time Vs. Distance.
Electra Model 10-E
Initial Gross Wt. 16,500#
Constant R.P.M. Propellers.
Pratt & Whitney S3H1 Engines
Zero Wind.
Performance at Best Power and Altitude.
24
170
analysis Range
prepared by W.C. Nelson.
date 5-18-36.
Gallons (100)
Millimeters, 10th line heavy.
Miles Per Hour.
160
20
150
FIGURE III.
140
8
16
6
12
4
6
130
Gallons of Fuel Consumed.
Elapsed Time, Hours.
4
0
0
0
1000
2000
Distance Covered in Miles.
3000
4000
9
page
model 10E
report No.
2
LOCKHEED AIRCRAFT CORP.
10
487
FORM 107
KEUFFEL & ESSER CO., N.Y.
NO. 359-14
Variation of Gross Weight, Power Output, and Cruising Altitude With Distance
Initial Gross Wt. 16,500#
Lockheed Electra Model 10-E
Zero Wind.
Constant R.P.M Propellers.
12
17
Gross Weight - Pounds
16
8
400 13
12
6
300 11
Optimum Power Output
Alternative Power Output
(see pg. )
10
200
9
4
100
2
0
0
1000
2000
Distance Covered – Miles.
3000
4000
10
page
model 10E
report no. 487
0
Altitude – 1000'
FIGURE IV.
Optimum Cruising Altitude
14
LOCKHEED AIRCRAFT CORP.
10
15
BHP.
analysis Range
prepared by W.C. Nelson.
date 5-18-36.
Weight (1000#)
Millimeters, 10th line heavy.
KEUFFEL & ESSER CO., N.Y.
NO. 359-11
20 X 20 to the inch.
analysis Range
prepared by W.C. Nelson.
date 5-18-36.
Miles Per Gallon Versus Altitude For Various Gross Weights and Power Outputs.
Constant Speed Propellers.
Zero Wind.
Gross Wt. 16,500#
Gross Wt. 12,900#
Gross Wt. 9300#
10
400 BHP.
300 BHP.
300 BHP.
250 BHP.
Altitude – 1000'
FIGURE V.
LOCKHEED AIRCRAFT CORP.
8
375 BHP.
350 BHP.
350 BHP.
200 BHP.
6
350 BHP.
250 BHP.
4
2
3.5
Miles Per Gallon
4.0
3.0
3.5
Miles Per Gallon
2.0
2.5
Miles Per Gallon
3.0
11
page
model 10E
report no. 487
0
3.0
FORM 107
KEUFFEL & ESSER CO., N.Y.
NO. 359-14
Millimeters, 10th line heavy.
1400
19,000
1200
analysis Range
prepared by W.C. Nelson.
date 5-18-36.
Fuel and Initial Gross Weight Necessary For a Given Range.
Constant R.P.M. Propellers.
Lockheed Electra Model 10-E
Zero Wind.
Performance at Best Power and Altitude.
18,000
Gallons of Fuel.
16,000
Gross Weight – Pounds.
FIGURE VI.
800
17,000
600
400
15,000
14,000
13,000
12,000
11,000
LOCKHEED AIRCRAFT CORP.
1000
10,000
9,000
200
1000
2000
Desired Range in Miles.
3000
4000
12
page
model 10E
report no. 487
0
analysis Range
prepared by W.C. Nelson.
date 5-11-36.
13
page
model 10E
report no. 487
LOCKHEED AIRCRAFT CORP.
FUEL CONSUMPTION
B.H.P. R.P.M.
OPTIMUM R.P.M., POWER, and
WEIGHT CONDITIONS FOR
ANY ALTITUDE
350
2000
350 BHP.
For 4100 mile
range.
300
1900
For 4500 mile
range
1800
300 BHP.
250
1700
250 BHP.
200 BHP.
.55
.45
.35
Spec. Fuel cons. (#/BHP/Hr.)
200
9300#
12,900#
Gross Weight.
16,000#
Miles Per Gallon Vs. Power Output at Various Altitudes.
10,000'
5,000'
S.L.
3.5
Mi./Gal.
20 X 20 to the inch.
KEUFFEL & ESSER CO., N.Y.
NO. 359-11
4.0
3.0
10,000'
5,000'
Gross Wt. 9300#
Gross Wt. 12,900#
S.L.
Gross Wt. 16,500#
5,000'
2,500'
S.L.
2.5
200
300
BHP.
200
300
BHP.
FIGURE VII.
300
400
BHP.
analysis Range
prepared by W.C. Nelson.
date 5-18-36.
14
page
model 10E
report no. 487
LOCKHEED AIRCRAFT CORP.
Miles Per Gallon Versus Fuel Load at
Optimum Power Output and Altitude.
5
4
3
2
1
0
0
300
600
900
1200
Miles Per Hour Versus Fuel Load.
M.P.H.
180
170
160
150
20 X 20 to the inch.
KEUFFEL & ESSER CO., N.Y.
NO. 359-11
140
130
0
300
600
900
1200
Fuel in Tanks - Gallons.
H.P.M.
Hours Per Mile Versus Distance Covered.
.0070
.0065
.0060
1000
2000
FIGURE VIII.
3000
4000
5000
analysis Range
prepared by W.C. Nelson.
date 5-20-36.
15
page
model 10E
report no. 487
LOCKHEED AIRCRAFT CORP.
Blade Angle in Degrees (.75R)
Thrust (#)
Take-off Characteristics.
Sea Level.
Gross Wt. 16,500#
H.S.C.S. Prop.
600 BHP/engine at 2300 r.p.m.
2200
Thrust
2000
1800
1600
1400
14
Blade Angle
1200
13
0
40
60
M.P.H.
80
2600
800
2400
600
2200
400
2000
O°
10°
20° 30°
Flap Angle.
40°
50°
200
FIGURE IX.
12
100
Effect of Flaps on
Rate of Climb.
600 BHP. Output.
Rate of Climb in
Ft./min.
Effect of Flaps on
Take-off Run.
600 BHP. Output.
Take-off Run
in Feet.
NO. 359-11
20 X 20 to the inch.
KEUFFEL & ESSER CO., N.Y.
20
O°
10°
20° 30°
Flap Angle.
40°
50°
Analysis – Range.
By – W. C. Nelson
Date – 5–19–36.
LOCKHEED AIRCRAFT CORP.
S E A L E V EL HP. REQUIRED CURVES
Vm.p.h.
q#/ft CL
87.5
19.5
1.85
90
20.8
1.73
95
23.1
1.56
100
25.5
1.41
105
28.0
1.29
110
30.9
1.17
120
36.8
0.98
130
43.1
0.84
140
50.0
0.72
2
150
160
Page – 16
Model – 10-E
Report – 487
57.4
65.0
0.63
0.55
FLAPS DOWN 30°
CD
HPREQ
.244
508
.218
498
.197
528
.179
556
.165
591
.151
626
.132
711
.119
815
.110
940
.104
.100
1092
1270
HPREQ. = DV = CDAqYmph. = 1.22 CDqVmph.
550 375
S E A L E V EL HP. AVAILABLE — 600 B.HP. — 2300 r.p.m. — FLAPS 30°
Vm.p.h.
90
95
100
105
110
120
130
140
/ ND .382
.403
.425
.446
.467
.510
.552
.595
V
C S
β
.72
15°
.76
15°
.80
16°
.84 16.5°
.88
17°
.96
17°
1.04
17°
1.12
18°
F L A PS NEUTRAL
V m.p.h.
T.HP
95
769
100
780
105
799
110
810
120
840
130
865
140
889
150
900
HP. REQ —
498
484
476
480
500
520
556
η
0.62
0.64
0.65
0.665
0.675
0.70
0.72
0.74
HP. ex .
—
282
315
334
360
365
369
344
T.HP.
745
769
780
780
810
840
865
889
HP REQ 498
528
556
556
626
711
815
940
RC
—
564 f.p.m.
630
668
720
730
7.38
688
HP ex. 247
241
224
224
184
129
50
–
RC
494 f.p.m.
482
448
448
368
258
100
–
Analysis Range
Prepared by C.L. Johnson
Date June 17, 1936
LOCKHEED AIRCRAFT CORP.
APPENDIX and COMPUTATIONS
*************************
FORM 100
19
Page
Model 10E
Report No. 487
Range
Analysis
W.C. Nelson
Prepared by
Date 5–19–36.
R-CLJ
LOCKHEED AIRCRAFT CORP.
Page 20
Model 10–E
Report No. 487
METHOD OF COMPUTATION
The basic horsepower required curves are developed from
flight test data and include an additional variation in "e" to
account for the change in propulsive efficiency with angle of
attack. Horsepower available curves are determined from the
engine propeller characteristics. From these curves the cruising
speeds at various power outputs and altitudes is determined and
the optimum power – r.p.m. conditions selected for the engine.
Complete data on the fuel consumption of the engine was not
available so generalized data on aircooled engines was used. (see
pg.
) From the known speeds and power outputs a chart of miles
per gallon for various gross weights and alittudes was derived.
From this chart the optimum power and altitudes for flight were
selected and a graph of miles per gallon versus fuel load at any
point during the trip was drawn up. Integration of this curve
yields the range. Similarly, integration of the hours per mile
versus miles travelled curve gives the elapsed time at any point
during the trip.
Range, elapsed time, optimum speeds, power output, and
altitude are then plotted on pgs.
and
.
A curve of the gallons of fuel necessary for any given range is also presented on
pg
.
Recommended Sea Level Engine Conditions.
Gross Wt.
Power
R.P.M.
Man. Pr.
9300#
200BHP.
1700
24.5 "Hg.
9300
250
1700
26.6
9300
300
1800
27.8
9300
350
1950
28.5
12,900
250
1700
26.6
12,900
300
1800
27.8
12,900
350
1950
28.5
16,500
350
1950
28.5
*
16,500
375
2100
28.5
*
16,500
400
2100
29.5
* Would only be used at altitude where max. cruising lim–
itations of 2000 r.p.m. and 28.5" Hg. would not be exceeded.
FORM 100
Analysis Range
Prepared by W.C. Nelson
Date 5–20–36.
LOCKHEED AIRCRAFT CORP.
21
Page
Model 10–E
Report No.487
COMPUTATIONS (continued)
Take-off will be considered with a gross weight of 16,500#
and a power output of 600 BHP. per engine at 2300 r.p.m. at sea
level. Schrenk's Method of analysis will be used. The following
table of take–off relationships is then derived.
V
V/ND
CP
b
CT
0 m.p.h. 0
.0418 12.9° .102
10
.030 .0418 12.9° .100
20
.061 .0418 13.0° .097
30
.091 .0418 13.1° .093
40
.121 .0418 13.1
.090
50
.152 .0418 13.2
.090
60
.182 .0418 13.3
.086
70
.312 .0418 13.4
.082
80
.242 .0418 13.7
.080
90
.273 .0418 13.8
.078
100
.303 .0418 14.0
.075
* Effective thrust includes a 7%
losses.
Thrust
Thrust(Effective)
2,320 #/prop. 2,160 #/prop.*
2,270
2,110
2,200
2,050
2,120
1,970
2,090
1,950
2,050
1,910
1,960
1,820
1,860
1,730
1,820
1,690
1,770
1,650
1,710
1,590
reduction factor due to tip
Then:
S = W
q1
1
g (P – P )
o
1
log P
e Po
1
S is the take—off run in ft.
1
W is the gross weight = 16,500#
g = std. air density = .0765 #/cu.ft.
q = take—off impact pressure.
1
P is the initial accelerating force. P the final.
o
1
.9 C
= 1.31
Lmax.
q = 27.5 #/sq.ft. (104 m.p.h.)
1
C = 0.148
D
P = T — mW = 4320 — .04 x 16,500 = 3650#
o
o
The coefficient of friction of .04 corresponds to a good
field with hard turf.
P = T — D = 3180 - .148 x 458 x 27.5 = 1317#
1
1
1
S = 16,500
27.5
log 3660 = 2590 ft.
1
e 1317
.0765 (3660 - 1317)
FORM 100
Analysis Range
Prepared by W.C. Nelson
Date 5–20–36.
LOCKHEED AIRCRAFT CORP.
Page 22
Model 10-E
Report No.487
COMPUTATIONS (continued)
Investigating the effect of flaps down 20°:
0.9 C
= 1.57
Lmax.
C = 0.183
D
P = 3660#
o
o = 23 #/sq.ft. (95 m.p.h.)
1
P = 1620 x 2 - 0.183 x 458 x 23 = 1310#
1
S = 16,500
23
log 3660 = 2180 ft.
1
e 1310
.0765
2350
Flaps down 30°:
0.9 C
= 0.9 x 1.35 = 1.67
Lmax.
C = 0.21
D
P = 3660#
o
q = 21.6 #/sq.ft. (92 m.p.h.)
1
P = 2 x 1660 - 0.21 x 458 x 21.6 = 1240#
1
S = 16,500 21.6
log 3660 = 2080 ft.
1
e 1240
.0765
2420
Flaps down 45°:
0.9 C
= 1.75
Lmax.
C = 0.243
D
P = 3660 #
o
q = 20.6 #/sq.ft.
1
P1 = 2 x 1660 - 0.243 x 458 x 20.6 = 1000#
S = 16,500
1
.0765
FORM 100
20.6
2660
log 3660
e 1040
= 2165 ft.
(89.5 m.p.h.)
Analysis Range
W.C. Nelson
Prepared by
Date 5–20–36.
LOCKHEED AIRCRAFT CORP.
23
Page
Model 10-E
Report No. 487
COMPUTATIONS (continued)
From the preceding calculations and graphs it is evidenct
that the minimum take-off run occurs with the flaps set at approximately 30°, when it is reduced some 20% from the unflapped run.
Computations for the rate of climb curves are included in
the appendix, pg.
.
FORM 100
FORM 107
KEUFFEL & ESSER CO., N.Y.
NO. 359-14
Millimeters, 10th line heavy.
Analysis Range
Prepared by W.C. Nelson.
Date 5-18-36.
Drag Polar and Variation of "e".
1.4
1.2
CD
= .029 + CL3
20.75 e
C
Gear Up
L
Gear Down
.8
Flaps 20°,
Gear Down.
Flaps 30°, Gear Down
.6
e
Flaps 45°, Gear Down.
.4
LOCKHEED AIRCRAFT CORP.
1.0
.2
0
.02
.04
.06
.08
.10
.12
.14
.16
.85
.75
e
24
Page
Model 10E
Report No. 487
0
Range
prepared byW . C. Ne l s on
page
analysis
date
5 – 18 – 3 6 .
LOCKHEED AIRCRAFT CORP.
model
report
25
10E
no. 487
PROPELLER CHARACTERISTICS
From NACA T. R. 351 , f ig.25
Appl i ed t o H. S. 5095–6
1.0
.8
28°
23°
.6
1.6
17°
12°
.4
28°
.2
1.2
23°
V/ND
1.0
17°
Millimeters, 10th line heavy.
NO. 359-14
0
KEUFFEL & ESSER CO., N.Y.
1.4
.8
12° at
.75 R
.6
.4
.2
0
0
FORM 107
.4
.8
1.2
C
S
1.6
2.0
2.4
2.6
analysis Range
prepared by W.C.
5-18-36.
Nelson
page
26
model 10E
report no. 487
LOCKHEED AIRCRAFT CORP.
Horsepower Required and Available Curves.
Constant R.P.M. Propellers Gross Wt. 16,500#.
H.P.
Sea Level
900
5,000’
10,000’
800
600
Millimeters, 10th line heavy.
KEUFFEL & ESSER CO., N.Y.
NO. 359-14
700
S.L.–350 BHP.-1800 r.p.m.
S.L.–350 BHP.-1900 r.p.m.
500
400
80
FORM 107
100
120
140
Velocity – M.P.H.
160
180
200
analysis Range
prepared by W.C.
5-18-36
Nelson
page
27
model 10E
report no. 487
LOCKHEED AIRCRAFT CORP.
Horsepower Required and Available Curves.
Constant R.P.M. Propellers Gross Wt. 12,900#
900
Sea Level
5,000’
10,000’
800
700
600
S.L.—550 BHP.—1900 r.p.m.
500
Millimeters, 10th line heavy.
KEUFFEL & ESSER CO., N.Y.
NO. 359-14
S.L.—550 BHP.—1800r.p.m.
S.L.—300 BHP.—1700 r.p.m.
S.L.—300 BHP.—1900 r.p.m.
400
S.L.—250 BHP.—1700 r.p.m.
S.L.—250 BHP.—1900 r.p.m.
300
80
100
120
140
Velocity — M.P.H.
FORM 107
160
180
200
analysis Range
prepared by W.C.
5-18-36
Nelson
28
page
10E
model
report no. 487
LOCKHEED AIRCRAFT CORP.
Horsepower Required and Available Curves.
Constant R.P.M. Propellers Gross Wt. 19,500#
800
Sea Level
5,000’
10,000’
700
600
S.L.—350 BHP.—1800r.p.m.
500
S.L.—350 BHP.—1900 r.p.m.
S.L.—300 BHP.—1700 r.p.m.
NO. 359-14
Millimeters, 10th line heavy.
KEUFFEL & ESSER CO., N.Y.
S.L.—300 BHP.—1900 r.p.m.
400
S.L.—250 BHP.—1700 r.p.m.
S.L.—250 BHP.—1900 r.p.m.
S.L.—200 BHP.—1500 r.p.m.
300
S.L.—200 BHP.—1700 r.p.m.
200
80
FORM 107
100
120
140
Velocity — M.P.H.
160
180
200
KEUFFEL & ESSER CO., N.Y.
NO. 359-14
Millimeters, 10th line heavy.
analysis Range
prepared by W.C.
5-18-36.
FORM 107
Change in Speed With R.P.M. at Constant Power Output.
Constant Speed Propeller Gross Wt. as Indicated.
350 BHP.
300 BHP.
250 BHP.
200 BHP.
28.5'' Man. Press. Limit
1900
Nelson
R.P.M.
16,500#
1800
9300 #
12,900#
9,300#
9,300#
1700
9300#
28.5'' Manifold Press. Limit
1600
LOCKHEED AIRCRAFT CORP.
12,900#
12,900#
1500
4
0
2
4
M.P.H. Increase in Speed.
0
2
4
0
2
4
487
2
page 29
model 10E
report no.
0
Analysis – Range
By – W.C. Nelson
LOCKHEED AIRCRAFT CORP.
Date – 5-18-36.
Vmph q% 65
70
75
80
85
90
95
100
110
120
130
140
150
160
170
180
190
200
SEA LEVEL HORSEPOWER REQUIRED CURVES
C L
C D
16,500# 12,900# 9,300#
10.9
12.5
14.4
16.4
18.5
20.8
1.36
23.1
1.22
25.5
1.41 1.11
30.9
1.17 0.91
36.8
0.98 0.77
43.1
0.84 0.65
50.0
0.72 .057
57.4
0.63 0.49
65.0
0.55 0.43
43.5
0.49 0.38
82.8
0.44 0.34
92.2
0.39 0.31
102.0
0.85 0.88
W = CLAqA = 458.3ft2
CL = 36.0 for
q
= 28.2 for
q
CL = 20.3 for
q
16,500# 12,900# 9,300#
1.41
1.24
1.10
0.98
0.147
0.88
0.123
0.80
0.160 0.106
0.66
0.115 0.080
0.55
0.089 0.665
0.47
0.073 0.055
0.41
0.061 0.049
0.55
0.53 0.043
0.31
0.041 0.040
0.28
0.049 0.38
0.25
0.040 0.036
0.22
0.038 0.034
0.20
0.036 0.033
Pg –30
Model – 10E
Report – 487
HP REQ.
16,500# 12,900# 9,300#
0.160
0.126
0.105
0.089 336
0.089 329
0.068
498 330
0.056
476 332
0.047
480 350
0.042
500 376
0.039
520 418
0.036
556 451
0.034
596 508
0.033
670 564
0.032
726 655
0.032
812 726
0.031
896 821
16,500#
12,900#
9,300#
HPREQ = DV = CDAq Vmph = 1.22 CDqVmph
550
375
211
202
201
203
206
212
232
253
887
333
378
431
503
581
684
771
Analysis – Range
By – W.C. Nelson
LOCKHEED AIRCRAFT CORP.
Date – 5-18-36.
Vm.p.h.
100
120
140
160
180
200
V/ND
100
120
140
160
180
200
.575
.690
.805
.920
1.035
1.150
100
120
140
160
180
200
.575
.690
.805
.920
1.035
1.150
100
120
140
160
180
200
.514
.617
.720
.822
.925
1.030
100
120
140
160
180
200
.575
.690
.805
.920
1.035
1.150
.651
.781
.912
1.042
1.172
1.302
SEA LEVEL
Cs
1.20
1.43
1.67
1.90
2.14
2.39
SEA LEVEL
1.13
1.25
1.48
1.80
2.03
2.26
SEA LEVEL
1.09
1.30
1.51
1.73
1.95
2.16
SEA LEVEL
1.04
1.24
1.45
1.65
1.85
2.06
SEA LEVEL
1.04
1.25
1.35
1.65
1.87
2.09
200 B.HP.
1500 r.p.m.
b
19°
21°
23°
25°
26.5°
28°
200 B.HP. 1700 r.p.m.
16°
20.5°
21.5°
21.5°
23°
24.5°
250 B.HP. 1700 r.p.m.
17°
19°
21°
22.5°
24°
25.5°
250 B.HP. 1900 r.p.m.
14°
16°
17°
19°
21°
22.5°
300 B.HP. 1700 r.p.m.
19°
21°
25°
23.5°
25°
26°
Pg –31
Model – 10E
Report – 487
0.74
0.77
0.785
0.77
0.74
0.72
T.HP.
148
154
157
154
148
144
0.73
0.76
0.77
0.72
0.70
0.64
146
152
154
144
140
128
0.74
0.76
0.77
0.76
0.745
0.71
185
190
192.5
190
186
178
0.70
0.73
0.74
0.72
0.70
0.66
175
183
185
180
175
165
0.72
0.76
0.765
0.78
0.77
0.75
216
228
230
234
231
225
η
Analysis – Range
By – W.C. Nelson
LOCKHEED AIRCRAFT CORP.
Date – 5-18-36.
Vm.p.h.
100
120
140
160
180
200
V/ND
100
120
140
160
180
200
.543
.651
.760
.869
.978
1.086
100
120
140
160
180
200
.514
.617
.720
.822
.925
1.030
120
140
160
.514
.617
.720
.822
.925
1.030
.690
.805
.920
SEA LEVEL 300 B.HP. 1900 r.p.m.
b
Cs
1.00
16°
1.20
17°
1.40
18.5°
1.60
20°
1.80
22°
2.00
23°
SEA LEVEL 350 B.HP. 1800 r.p.m.
1.00
18°
1.20
19°
1.40
21°
1.60
22°
1.80
23.5°
2.00
25.5°
SEA LEVEL 350 B.HP. 1900 r.p.m.
0.97
17°
1.16
18°
1.35
20°
1.54
21°
1.74
22°
1.93
24°
5,000' 200 B.HP. 1700 r.p.m.
1.32
18°
1.55
20°
1.75
22°
5,000'
120
140
160
180
.651
.760
.869
.978
1.24
1.46
1.65
1.85
5,000'
120
140
160
180
.617
.720
.822
.925
250 B.HP.
300 B.HP.
1.17
1.36
1.56
1.75
Pg –32
Model – 10E
Report – 487
0.71
0.75
0.76
0.75
0.74
0.71
T.HP.
213
225
228
225
222
213
0.71
0.75
0.77
0.77
0.77
0.76
248
262
270
270
270
266
0.70
0.74
0.76
0.77
0.75
0.74
245
259
266
270
262
259
η
σ 1/5 = 0.972
0.76
0.76
0.75
152
152
150
σ 1/5 = 0.972
1800 r.p.m.
18°
19°
21.5°
23°
0.76
0.76
0.76
0.755
190
190
190
189
σ 1/5 = 0.972
1900 r.p.m.
17.5°
19°
21°
22.5°
0.75
0.76
0.76
0.76
225
228
228
228
Analysis – Range
By – W.C. Nelson
LOCKHEED AIRCRAFT CORP.
Date – 5-18-36.
Vm.p.h.
120
140
160
180
140
160
180
100
120
140
160
180
200
140
160
180
V/ND
.651
.760
.869
.978
.720
.822
.925
.465
.559
.651
.745
.848
.930
.651
.745
.848
10,000' 250 B.HP.
Cs
1.21
1.42
1.60
1.79
10,000' 300 B.HP.
1.32
1.51
1.70
120
140
160
180
.651
.745
.848
.559
.651
.745
.848
18.5°
20°
22°
24°
1900 r.p.m.
20°
22°
23°
SEA LEVEL 400 B.HP. 2100 r.p.m.
0.90
15°
1.08
19°
1.26
17°
1.44
18°
1.62
21°
1.80
22°
5,000' 400 B.HP. 2100 r.p.m.
1.22
18.5°
1.40
20°
1.557
21.5°
10,000'
140
160
180
1800 r.p.m.
b
400 B.HP.
1.19
1.36
1.53
SEA LEVE 375 B.HP.
1.102
1.29
1.47
1.66
η
0.75
0.77
0.78
0.78
Pg –33
Model – 10E
Report – 487
T.HP.
188
193
195
195
σ 1/5 = 0.943
σ 1/5 = 0.943
0.76
0.78
0.78
228
234
234
0.68
0.715
0.76
0.76
0.75
0.74
272
286
304
304
300
296
σ 1/5 = 0.943
0.75
0.77
0.76
300
308
316
σ 1/5 = 0.943
2100 r.p.m.
20°
21°
23°
0.75
0.77
0.79
300
308
316
2100 r.p.m.
15°
17°
18°
20°
0.72
0.76
0.75
0.74
270
285
281
278
Analysis – Range
By – W.C. Nelson
LOCKHEED AIRCRAFT CORP.
Date – 5-18-36.
Pg –34
Model – 10E
Report – 487
9300# GROSS WEIGHT
B.HP./ENG. R.P.M. MAN. PR.
350
300
250
200
350
300
250
350
400
350
400
375
1950
1950
1950
1800
1800
1800
1700
1700
1700
1700
1700
1700
28.5 "Hg
26.5
24.6
27.8
25.8
23.7
26.6
24.5
22.5
24.5
22.5
20.5
1950
1950
1950
1800
1800
1800
1700
1700
1700
28.5
26.5
24.6
27.8
25.8
23.8
26.6
24.5
22.5
1950
1950
1950
2100
2100
2100
1950
2100
2100
2100
2100
28.5
26.5
24.6
29.5
27.2
25.5
28.5
28.5
28.5
26.5
24.5
ALTITUDE
SPEED
S.F.C.
0 ' 174 m.p.h. 0.46#/BHP.HR.
5,000
181
0.46
10,000
189
0.46
0
164
0.465
5,000
170
0.465
10,000
177
0.465
0
151
0.47
5,000
157
0.47
10,000
162
0.47
0
135
0.515
0.515
139
5,000
143
0.515
10,000
12,900# GROSS WEIGHT
0
165
0.46
5,000
170
0.46
10,000
175
0.46
0
152
0.465
5,000
156
0.465
10,000
158
0.465
0
133
0.47
5,000
133
0.47
10,000
—
—
16,500# GROSS WEIGHT
0
144
0.46
5,000
128
0.46
10,000
—
—
0.465
0
162
164
0.465
5,000
10,000
159
0.465
2,500
141
.046
2,500
163
0.465
0
153
0.46
5,000
151
0.46
10,000
143
0.46
TOTAL FUEL CON.
IN GAL.. PER HR.
MILES PER GAL.
HR./GAL.
53.6
53.6
53.6
46.5
46.5
46.5
39.2
39.2
39.2
34.3
34.3
34.3
3.24
3.37
3.52
3.52
3.66
3.8
3.85
4.00
4.14
3.93
4.05
4.17
.0186
.0186
.0186
.0215
.0215
.0215
.0255
.0255
.0255
.0291
.0291
.0291
53.6
53.6
53.6
46.5
46.5
46.5
39.2
39.2
—
3.07
3.17
3.26
3.27
3.36
3.40
3.39
3.39
—
.0186
.0186
.0186
.0215
.0215
.0215
.0255
.0255
—
53.6
53.6
—
62.0
62.0
62.0
53.6
62.0
57.5
57.5
57.5
2.68
2.38
—
2.61
2.65
2.56
2.63
2.63
2.66
2.62
2.48
.0186
.0186
—
.0161
.0161
.0161
.0186
.0161
.0174
.0174
.0174
Analysis – Range
By – W.C. Nelson
LOCKHEED AIRCRAFT CORP.
Date – 5-18-36.
Values Derived From
FUEL
DISTANCE
USED
COVERED
300 gals. 846 mi.
600
1812
900
2880
1200
4080
0
0
Pg –35
Model – 10E
Report – 487
Graphical Integration of Miles Per Gallon Vs. Fuel Load Curve.
OPTIMUM HOURS
SPEED
PER MILE
160 m.p.h. .00625
153
.00633
153
.00654
143
.00700
162
.00617
Values Derived From Graphical Integration of Hours Per Mile Vs. Distance Covered.
DISTANCE
COVERED
1,000 mi
2,000
3,000
4,000
ELAPSED
TIME
6.20 hrs.
12.49
18.97
25.68
DISTANCE
DESIRED
FUEL
NECESSARY
GROSS
WEIGHT
0 miles
500
1000
2000
3000
4000
0 GAL.
120
244
520
820
1165
9,300#
10,020
10,764
12,420
14,220
16,240

Similar documents