Jeppesen CR-3, Manual

Page 1: ...he CR 33 Conversions 5 Flight Planning with Weight of Fuel and Oil 9 Forecast Winds 37 Finding Winds in Flight 41 Altitude 11 True Cow se Track and Density Altitude 12 Ground Speed 44 True Altitude 12...

Page 2: ...autical Statute Conversion Arrows 0 Calibrated Air Speed Window G Time Index 0 True Air Speed Windows 0 Base Disc CR 5 0 Top Disc 0 Temperature Conversion Scale G Indicated Temperature Window 4D Mach...

Page 3: ...g you first a word about reading the scales on the C R Each figure on the outer scales of the compu ter can stand for any number con taining the given digits T he poim marked 40 can tand lor I 1 40 40...

Page 4: ...lled 105 U S g lllorr ol g r olinc in I hr 30 lllrll f ind Gallon J l r hour and potrrrd per hour 4 1 CONVERSIONS Thing arcrr t al ay what OU want them to he But the CR will help Oll change thcn1 For...

Page 5: ...tttiral mi le etc It would also have been possible to 111atch the ST TUT E arrow on the out iclc c tle with the NAUTICAL arrow on the in idc s a lc reading latu te mi les on the outside scale and naut...

Page 6: ...er Service express altitudes in meters instead of feet That is no trouble at all The CR makes the conversion by lining up the meters arrow near 44 on the inner scale and the feet arrow near 14 on the...

Page 7: ...Oppo itc SEC a11ow ncar 3G on inside scale read 81 Answer 1312 minute 810 SC 011 1 10 ALTITUDE Altitude comes in assorted V ll ieties Ever wonder how high 1s up No need for confusion if you remember t...

Page 8: ...calibrated altitude or indicated if calibrated is not available and true air temperature Greater accuracy can be obtained if you also know the altitude of the ground station giving your altimeter set...

Page 9: ...C R computer 14 While either knots or MPH can be used with the CR Modern True Air Speed Solution more accurate true air speed answers will result from using knots when dealing with speeds over 200 Th...

Page 10: ...ed scale T his value indi cates that the aircralt is flying at 78 times the speed ol sound Since 1 rath Number is dependent upon the speed of sound which varies only with tempera ture the same 1 Iach...

Page 11: ...ue air speed out lined in Figs 12 and 13 make use of i11dicated air temperature See the following section for the he t method of finding true air speed when true air temperature is available 18 True A...

Page 12: ...h a CT of 8 the Or 8 cursor line is used and the vaJue found on the TEMPERA TURE RISE C0 Or 1 0 scale is muJtiplied by 8 Given Find 20 Example Calibrated air speed 276 kts Pressure altitude 10 000 Ind...

Page 13: ...the shortest way home See the Jeppesen CR Computer Manualj tVorkbook or a good m1vigation text lor funher explanation of pressure paltern naviga tion However if you already know something about it he...

Page 14: ...es are approximately equivalent to those of a 12 straight rule The 6 diameter CR 3 scales are equivalent to those of a 17 straight slide rule and the 33 4 CR 5 scales equal a 10 rule Multiplication an...

Page 15: ...te answer by replacing numbers in problem by numbers that arc close in value but easier to multiply and divide For instance in problem above the figures are similar 25 X to 20 which equals 12 5 H ence...

Page 16: ...ation Solution Time to Station Elapsed time min x 60 Degrees of change 3 X 60 g On calculator side set 3 on outside scale opposite 9 on inside scale Opposite 60 1 00 on inside scale read answer on out...

Page 17: ...Only Dual 0 thru 180 scales for grid navigation problems adding and subtracting and other uses 4 CR 3 Only Clockwise 0 thru 360 scale for ADf relative bearing solutions and other usc 3 and 4 above arc...

Page 18: ...btract 29 from 8 1 locate 29 on sotle to the left o TC index and above 29 read 55 32 WIND SOLUTION ON THE C R The wind side of the CR IS a diiTcrem looki ng gismo but this is nothing to be shook up ab...

Page 19: ...ally and you con put thl C R in your pockel In the wind triangle above il you draw a line rom the end of the TH TAS line perpendicular to the TC GS line you will have a small triangle at the top of th...

Page 20: ...calc fr01n 0 wHO if tht wind i less than 80 knot or i 1PI I l e tht s1nall r tlc fmnt 0 to lliO if the wind is more than 80 011 e Oil h I C hmcn the dc ired lcalc me it throu hmn the p1ohlent taking C...

Page 21: ...ation II 0 W vVind 40 J IPH from 100 True Find Crab Angle 1 fagneti H eading and Ground Speed Solution Sec Fig J 1 Keep the true air speed index on 180 PH and merely rotate the green se tle to line up...

Page 22: ...T Quite often after you get upstairs you find the wind is not behaving as the weather guesser said it would You must hold a different heading from that originally estimated in order to make good your...

Page 23: ...lwind component which you will spot on your computer Jn this example 17 i IPH ETAS 144 MPH C S 30 MPH headwind From the 30 l IPH headwind figure draw a line to the left Left crab wind from the left 6...

Page 24: ...ather than true course under the 0 index This selling is only a temporary one to give an approximate crab angle to u c in dcL Jtllinin the actual true tour c The top di t ill he IIHncd a ain II tltat...

Page 25: ...e tailwind component directly to the true a ir speed Howe er i nce the nab angle in this problem i grellter than 10 it i nen ary to u c t frr i71 lrur air sjJeNI in finding ground IJ ed Find 13 o n th...

Page 26: ...er and note that it i clo e to I o nab angle on the inner Cale 6 Since the rab lllgle i grc 11er than 10 the figure 186 in tep 1 aho e nHL t he 1 ntn t llllf air sf t nl lath l than true air peed L01...

Page 27: ...T his need not be di trcssi ng if yc11t tHinue on Our original heading until you reach a recogni73ble heck point lea ul your di tance ofT wur e utile llown and mile to destina 1ion T hen two ea rom p...

Page 28: ...of drift will give approximately 1 mile off course in 60 5 Add the degrees correction necessary to parallel your course and the additional correction necessary to reach destination to get the total c...

Page 29: ...angle on the outbound course becomes the same size left crab angle on the inbound course 0 Fig 35 54 1 Subtract the 18 kt headwind component from the TAS to get G S out 285 18 267 2 Add the 18 kt tai...

Page 30: ...4 F 12 10 C PROBLEMS 3 PROBLEMS 4 1 70 meters 3 25 meters 1 210 lbs 3 450 lbs 2 11 480 feet 4 18 040 feet 2 3 603 lbs 4 135 lbs PROBLEMS 5 PROBLEMS 6 1 4 100 feet 2 2 820 feet 3 6 890 feet 1 12 200 fe...

Page 31: ...icated Altitude A Altitude read on a standard altimeter assuming the altimeter is correctly adjusted to show the approximate heighl of th1 aircraft above mean sea level MSL Calibrated Altitude CAl Ind...

Page 32: ...c eut unit or I in tc ul of llllih or Ill Ill get the wintl dill 3W3 rnun the lCnter rur ea ICI rc cl ing 111 T nnt lH t approach wi ll gi1e T S ing the modern method rrum reponed tcmpCI lttlle withou...